DE102012204787A1 - Engine starter control device for vehicle, performs OFF setting time abnormality detection processing for detecting fault in load-side and energy-side switching units, based on voltage of intermediate switch path between switching units - Google Patents

Abstract

The device has electrical loads (19a,23a) to drive starter (13), and load-side switching units (27,28) and energy-side switching unit (29) provided in path between electric loads and power source (15). Each switching unit includes two contacts (27b,27c,28b,28c,29b,29c). The abnormality detection units (31,50) monitors voltage of intermediate switch path (Lm) between switching units, while switching units are maintained in OFF state. The OFF setting time abnormality detection processing is performed for detecting fault in switching units, based on monitored voltage.

Description

The present invention relates to a starter control device that starts an internal combustion engine of a vehicle to start.

In a conventional starter for starting an internal combustion engine, which in the JP 2001-207942A is disclosed, when a battery voltage (positive terminal voltage of a battery) is provided to one end of a solenoid coil whose other end is connected to a ground line (negative terminal side of the battery), electromagnetic force is generated by energizing the coil. With this electromagnetic force, a pinion engages with a ring gear of the internal combustion engine, and an electromagnetic switch provided in a power supply path is turned on (that is, a switching contact is closed) to rotate about an electric motor for driving the pinion. Thus, the electric motor is supplied with power.

In this starter type, by supplying the coil of the solenoid with current, the pinion engages with the ring gear and the electric motor is energized to apply a rotational driving force for rotating the pinion as an operation for performing a starter function. The starter function means that a starter is operated to start the internal combustion engine. The solenoid is an actuator that includes a coil and a movable part, such as a piston, which is operated by electromagnetic force of the coil.

In a control device for controlling this type of starter, a starter relay provided as a switch between the coil of the solenoid provided in the starter and the battery terminal is turned on to drive the coil of the solenoid through the starter relay Power supply, whereby the starter is operated.

In another type of conventional starter, in the JP H11-30139A is disclosed, a pinion is configured to switchably intervene without interfering with the power supply of the electric motor in the ring gear of the internal combustion engine.

Concretely, in this starter type, a solenoid for setting the pinion so as to mesh with the ring gear and a large electromagnetic switch are independently provided in a power supply path toward the electric motor. That is, the coil of the solenoid for driving the pinion and the coil of the electromagnetic switch for supplying the electric motor with the power are provided separately. This type of starter is referred to as an independently controlled starter because the pinion and the electric motor are independently controllable.

According to the control apparatus for an independently controlled starter, the starter is operated by turning on a pinion setting relay and an electric motor adjusting relay. The pinion positioning relay is provided as a switch in a power supply path from the battery terminal to the solenoid coil. The motor control relay is provided in a power supply path from the battery terminal to the coil of the electromagnetic switch.

JP H11-30139A also discloses an automatic stop and start system for an internal combustion engine, commonly referred to as an idling stop system, which automatically stops an internal combustion engine when a predetermined stop condition is met and automatically restarts the internal combustion engine when a predetermined start condition is met. According to the independently controlled starter, it is possible, for example, to lock pinions in the ring gear of the internal combustion engine before the starter motor (motor or electric motor of the starter) is operated. Thus, since the wear of mechanical parts such as the pinion is reduced and the life of the starter is prolonged, the independently controlled starter is suitable for use in an idling stop vehicle in which the starter is operated more frequently than before.

In the control device for operating the starter by turning on the starter relay (that is, control device for operating the starter that is not independently controlled) when an ON fault (fault that the starter relay continuously remains in the ON state) in the starter relay occurs, the current in the coil of the solenoid continues to operate or to operate the starter. As a result, the pinion of the starter is continuously latched into the ring gear and the electric motor continues to operate.

In the control device for operating the starter by turning on the pinion setting relay and the electric motor adjusting relay for operating the starter as well (that is, the control device for operating the starter which is independently controlled) when an ON fault occurs in the pinion setting relay, a current flows in the Coil of the solenoid to operate the pinion on. Consequently, the pinion of the starter is continuously latched in the sprocket. When an ON fault occurs in the motor control relay, a current flows in the coil of the electromagnetic switch to operate the motor Electric motor continues. As a result, the electric motor continues to operate or the electric motor continues to operate.

In each of the conventional control devices, the pinion and / or the electric motor are operated unnecessarily even at a time other than the starting time of the internal combustion engine.

It is an object of the present invention to provide a starter control apparatus which avoids that a functional part of a starter is unnecessarily operated even when a switch having an ON fault in a power supply path for supplying an electric load with power for driving the starter ,

According to the present invention, there is provided a starter control apparatus for a vehicle having an electric load for driving a starter for starting a motor. One end of the electrical load is connected to a first potential, which is either a potential of a high potential side or a low potential side of a power source. The starter control device has a power supply switching means and an abnormality detecting means.

The power supply switching means is provided in a current path formed between the other end of the electric load and a second potential that the other potential is from the high potential side and the low potential side of the power source. The power supply switching means is turned on to provide a current to the electrical load. The power supply switching means includes an energy side switching means and a load side switching means. The power-side switching means has a pair of contacts, one of which is connected to the second potential. The load side switching means has a pair of contacts, one of which is connected to a contact opposite to the other contact of the power side switching means, and the other is connected to the other end of the electric load.

The abnormality detecting means monitors a voltage of an inter-switch path between the power-side switching means and the load-side switching means while controlling the power-side switching means and the load-side switching means in OFF states. The abnormality detecting means performs OFF-positioning-time abnormality detection processing for detecting an ON-failure of one of the power-side switching means and the load-side switching means based on a monitored voltage.

The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the drawings.

In the drawings:

1 Fig. 10 is a circuit diagram illustrating a starter control apparatus according to a first embodiment of the present invention;

2 Fig. 12 is a circuit diagram illustrating a relationship between threshold voltages of comparators and a power source voltage and supply voltage, respectively;

3 Fig. 10 is a timing chart illustrating a sequence of operation of an internal combustion engine;

4 Fig. 13 is a table showing relationships among detected abnormalities, relay setting states and comparator outputs in the first embodiment;

5 is a table that shows relationships between failure modes and resilience processing;

6 Fig. 10 is a flowchart illustrating an abnormality detection processing in the first embodiment;

7 Fig. 10 is a flowchart illustrating the fail-safe processing executed in the abnormality detection processing in the first embodiment;

8th Fig. 10 is a circuit diagram illustrating a starter control apparatus according to a second embodiment of the present invention;

9 FIG. 12 is a table showing relationships among detected abnormalities, relay setting states and comparator outputs in the second embodiment; FIG.

10 Fig. 10 is a flowchart illustrating abnormality detection processing in the second embodiment; and

11 FIG. 10 is a flowchart illustrating fail-safe processing executed in the abnormality detection processing in the second embodiment. FIG.

A starter control device will be explained with reference to embodiments.

First Embodiment

According to 1 become electronic control units (ECUs) 11 and 12 prepared to cooperatively start a starter 13 to control the starting of an internal combustion engine for starting an internal combustion engine of a vehicle. The ECU 11 is configured to perform an idling stop control operation that automatically stops the engine and automatically restarts it. The ECU 12 is configured to monitor if the ECU 11 operated normally. The vehicle is assumed to have manual abnormality detection processing of 6 acquisition of data by

The ECU 11 receives a starter signal, a brake signal, a throttle signal, a clutch signal, a shift position signal, a vehicle speed signal, a brake vacuum signal, a rotation signal, and the like. The starter signal becomes active when a driver of the vehicle performs a start-up operation (for example, turning a key inserted in a key cylinder to a start position). The brake signal is output from a sensor that detects a brake operation by a brake pedal. The gas signal is output from a sensor that detects a gas operation by an accelerator pedal. The clutch signal is output from a sensor that detects a clutch operation on a clutch pedal. The shift position signal is output from a sensor that detects a shift lever position (shift position). The vehicle speed signal is output from a sensor that detects a vehicle speed (vehicle speed). The brake vacuum signal is output from a sensor that detects a brake vacuum or a brake vacuum (negative pressure of a brake booster). The rotation signal is input from a crankshaft sensor or a camshaft sensor. The ECU 11 also receives a battery voltage VB (for example, 12 volts) connected to a positive terminal of a battery 15 , which is installed as an energy source in the vehicle, is developed at a terminal 14 for battery voltage monitoring. In the case that the battery voltage VB is provided to an ignition system power line (that is, when the ignition is turned on), the ECUs operate 11 and 12 with electrical energy provided by the ignition system power line.

A starter 13 includes an electric motor (starter motor) 17 which is a drive power source for starting the internal combustion engine, an electromagnetic switch 19 that the electric motor 17 energized to put this or operate, a pinion 21 that by the electric motor 17 is driven to rotate, and a pinion control solenoid 23 that the pinion 21 puts to the sprocket 25 intervene.

One end of the electric motor 17 is connected to a ground line (GND) connected to the negative terminal side of the battery 15 is. The electromagnetic switch 19 is a large-sized relay that is in a power supply path from a power supply line 16 (positive connection side of the battery 16 ) of the battery voltage VB to the other end of the electric motor 17 provided. The electromagnetic switch 19 is selectively set to an ON state (turned on) for connecting the power supply path and to an OFF state (turned off) for disconnecting the power supply path.

Specifically, the electromagnetic switch includes 19 a coil 19a , a pair of solid contacts 19b and 19c and a moving contact. One end of the coil 19a is connected to the ground line. The contacts 19b and 19c are in the power supply path to the electric motor 17 intended. The battery voltage VB is applied to the other end of the coil 19a for feeding the coil 19a Created, the contacts become 19b and 10c short-circuited by the movable contact to form the power supply path (this is the ON state). Will the coil 19a not fed are the contacts 19b and 19c open and disconnect the power supply path (this is the OFF state).

The pinion control solenoid 23 includes a coil 23 of which one end is connected to the ground line, and a biasing member (not shown) such as a spring. Will the coil 23a not fed, the pinion becomes 21 to an initial position (in 1 shown) biased and from the sprocket 25 disengaged by a force of the biasing member. The battery voltage VB is applied to the other end of the coil 23a created and becomes the coil 23a fed, the pinion becomes 21 driven by the electromagnetic force generated by the power supply, or placed in the outward direction of the starter 13 as indicated by a dot-dashed arrow in 1 protruding so that it is in the sprocket 25 intervenes.

Will the electric motor 17 by switching the electromagnetic switch 19 fed, with the pinion 21 in the sprocket 25 engages, the rotational force of the electric motor 17 on the sprocket 25 through the pinion 21 transferred, whereby the internal combustion engine is started.

A pinion control relay 27 is outside of the ECUs 11 and 12 intended. When turned on, sets the pinion control relay 27 the battery voltage VB to the other end (upstream or high potential side: opposite side to the ground line or low potential side) of the coil 23 to get a current to power the coil 23a provide so the pinion 21 in the sprocket 25 intervenes.

An electric motor control relay 28 will also be outside the ECUs 11 and 12 provided. When turned on, sets the electric motor control relay 28 the battery voltage VB to the other end (upstream or high potential side: the ground line opposite side or low potential side) of the coil 19a to the coil 19a to provide a current so that the electromagnetic switch 19 is switched on and the electric motor 17 is fed.

An energy tax relay 29 is on the upstream sides of both the pinion positioning relay 27 , as well as the electric motor control relay 28 and in a common power path from the power line 16 the battery voltage VB to the relay 27 and 28 provided to connect and disconnect this current path.

Specifically, the energy tax relay indicates 29 a coil 29a , a pair of solid contacts 29b and 29c and a moving contact. One end of the coil 29a is connected to receive the battery voltage VB, and the other end thereof is through the ECU 12 earthed (connected to the ground line). The contacts 29b and 29c are shorted by the moving contact when the coil 29a through the ECU 12 is fed. The contact 29b is with the power line 16 the battery voltage VB connected. Will the coil 29b fed, the contacts become 29b and 29c shorted (this is the ON state of the power control relay 29 ) and the battery voltage is from the contact 29c to the sides of the pinion control relay 27 and the electric motor control relay 28 output.

The pinion control relay 27 includes a coil 27a , a couple of contacts 27b and 27c and a moving contact. One end of the coil 27a is connected to receive the battery voltage VB and the other end thereof is through the ECU 11 grounded. The contacts 27b and 27c are shorted by the moving contact when the coil 27a is fed. The contact 27b is with the contact 29c of the energy tax relay 29 connected and the contact 27c is at the other end (upstream side) of the coil 23a connected. Will the coil 27a fed, the contacts become 27b and 27c short circuited (this is the ON state of the pinion control relay 27 ) and the contact 29c of the energy tax relay 29 and the coil 23a are connected.

The electric motor control relay 28 includes a coil 28a and a few contacts 28b and 28c , One end of the coil 28a is connected to receive the battery voltage VB and the other end thereof through the ECU 11 grounded. The contacts 28b and 28c be shorted when the coil 28a is fed. The contact 28b is with the contact 29c of the energy tax relay 29 connected and the contact 28c is at the other end (upstream side) of the coil 19a connected. Will the coil 28a fed, the contacts become 28b and 28c short-circuited (this is the ON state of the electric motor relay or electric motor control relay 28 ) and the contact 29c of the power control relay and the coil 19a are connected.

The energy tax relay 29 and the pinion control relay 27 are in series in the power supply path from the battery voltage VB to the coil 23a arranged as a switch which connects and disconnects the current path. The energy tax relay 29 and the electric motor control relay 28 are in series in the current path from the battery voltage VB to the coil 19a arranged as a switch which connects and disconnects the current path. The energy tax relay 29 is in a common current path of the coil 19a and 23a arranged. That is, a series circuit through the pinion control relay 27 and the coil 23a is formed, and a series circuit by the Elektromotorstellrelais 28 and the coil 19a is formed in series with the energy control relay 29 and arranged parallel to each other.

By switching on the control relay 29 and the pinion control relay 27 becomes the coil 23a fed, leaving the pinion 21 in the sprocket 25 intervenes. By further switching on the electric motor control relay 28 becomes the coil 19a fed, so that the electric motor, the Rotationsstell- or driving force on the pinion 21 , As a result, the engine is driven by the starter 13 started.

The ECU 11 includes a microcomputer 31 , an input circuit 33 , two resistances 35 and 37 and a capacitor 39 , The microcomputer 31 performs different processings for an idling stop control operation and a starter control operation. The input circuit 33 gives different signals, like the starter signal into the computer 13 one. The resistors 35 and 37 proportionally divide the battery voltage VB through the terminal 14 is entered for battery voltage monitoring, in a voltage that in one for the microcomputer 31 suitable area. The capacitor 39 is between a voltage line, a junction of the resistors 35 . 37 and the ground line for filtering noise. The microcomputer 31 detects the battery voltage VB by A / D conversion the divided voltage between the resistors 35 and 37 is developed by its internal A / D converter (not shown). The microcomputer 31 detects voltage values of the analog signals coming from the input circuit 33 be entered by A / D-converting the same through the internal A / D converter.

The ECU 11 includes terminals J1, J2 and transistors T1, T2. The terminal J1 is connected to the downstream or low potential side of the coil 27a connected (that is, opposite side of the battery voltage VB). The J2 connector is on the downstream side of the coil 28a connected (that is, opposite to the side of the battery voltage VB). The transistor has two output terminals connected between the terminal J1 and the ground line. The transistor T2 has two output terminals connected between the terminal J2 and the ground line.

Transistors T1 and T2 are provided to pass through the microcomputer 31 to be controlled. When the transistor T1 is turned on, the coil becomes 27a fed and the pinion relay 27 switched on. When the transistor T2 is turned on, the coil becomes 28a fed and the electric motor control relay 28 switched on. Transistors T1 and T2 are N-channel MOSFETs.

One end of an abnormality detection wire Lm is at a predetermined position P in a current path (intermediate switching path) of the power control relay 29 to the pinion control relay 27 and the electric motor control relay 28 connected. The wire Lm does not necessarily have to be connected to the point P.

The other end of the wire Lm is connected to a terminal J3 of the ECU 11 connected. Thus, a voltage in the current path between the pinion control relay 27 and the electric motor control relay 28 is developed as an intermediate relay voltage of the ECU 11 entered through port J3.

The ECU 11 includes a so-called pull-up resistor R1, a so-called pull-down resistor R2 and a voltage monitoring circuit 50 for detecting errors of the three relays 27 to 29 , The pull-up resistor R1 is connected between the terminal J3 and the battery voltage line (VB). The pull-down resistor R2 is connected between the terminal J3 and the ground line J3. The voltage monitoring circuit 50 monitors the terminal voltage (intermediate relay voltage) Vm developed at terminal J3.

The voltage monitoring circuit includes two comparators 51 and 52 , a pull-up resistor 53 , a pull-up resistor 54 , two resistances 55 and 56 and two resistors 57 and 58 , Both non-inverting input terminals (positive terminals) of the comparators 51 and 52 are connected to terminal J3. The pull-up resistor 53 is between a voltage line of a fixed voltage VD (5V), which is inside the ECU 11 is developed, and an output terminal of the comparator 51 connected. The pull-up resistor 53 is between the voltage line of a fixed voltage VD (5 V) and an output terminal of the comparator 52 connected. The resistors 55 and 56 divide the battery voltage VB and input the divided voltage into an inverting input terminal (negative terminal) of the comparator 51 as a first threshold voltage Vth1. The resistors 57 and 58 Divide the battery voltage VB and give the divided voltage to an inverting input terminal (negative terminal) of the comparator 52 as a second threshold voltage Vth2.

Output signals CM1 and CM2 of the comparators 51 and 52 be in the microcomputer 31 entered. Each output circuit within the comparator 51 and 52 is of the current consumption type (open collector or open drain). Because of this, pull-up resistors 53 and 54 provided so that the comparators 51 and 52 Output signals with high levels (5 V).

It is necessary that even if the pinion control relay is turned on, the power control relay 29 in the OFF state, that is the coil 23 for its operation (switching on) is not supplied with a current (for example, more than 10 amps). It is also necessary that even if the electric motor control relay 28 is turned on, with the power control relay in the OFF state, the coil 19a for its operation (switching on) is not supplied with a current (for example, more than 10 amps). The resistance r1 of the resistor R1 is therefore set sufficiently large, for example, in a range of several thousand times to several tens of thousands times the resistance values of the coils 19a and 23a ,

Further, the resistance value r1 of the resistor R1 and the resistance value r2 of the resistor R2 are set to be equal to each other. For example, the resistance values r1 and r2 are set to 10 KΩ. Accordingly, if the three relays 27 to 29 are all in the OFF states, the terminal voltage Vm is equal to a voltage resulting from a division of the battery voltage VB by the resistance values r1 and r2, that is, one-half (1/2) of the battery voltage VB, as in FIG 2 is shown.

In the voltage monitoring circuit 50 , the resistance values of the resistors 55 and 56 set to satisfy a ratio of 1: 3, so that the first threshold voltage Vth1 applied to the comparator 51 is applied three quarters (3/4) of the battery voltage VB, as in 2 is shown. The contradictory values of the resistances 57 and 58 are set to satisfy a 3: 1 ratio, so that the second threshold voltage Vth2 applied to the comparator 52 a quarter (1/4) of the battery voltage VB is applied, as in 2 is shown.

The microcomputer 31 in the ECU 11 detects abnormalities of the relays 27 to 29 based on a correspondence relationship between the states of the relays 27 to 29 and the output signals CM1 and CM2 of the comparators 51 and 52 as further explained in detail below.

The ECU 12 includes a microcomputer 41 , a terminal J4 and a transistor T3. The J4 terminal is at the downstream or low potential side of the coil 29a connected (opposite side of the side of the battery voltage VB). The transistor T3 has two output terminals connected between the terminal J4 and the ground line. When the transistor T3 is turned on, the coil is energized and the power control relay 29 is turned on. The transistor T3 is also an N-channel MOSFET.

The microcomputer 41 the ECU 12 is through a communication line 43 with the microcomputer 31 for communication with the microcomputer 31 connected. The microcomputer 41 turns on transistor T3 in response to instructions from the microcomputer 31 that as a result of communication with the microcomputer 31 be generated, on and off.

The microcomputer 41 in the ECU 12 checked based on communication with the microcomputer 31 whether the microcomputer 31 operated normally. Definitely the microcomputer 41 that the microcomputer 31 not normally operated, the microcomputer causes 41 the transistor T3 remains OFF, regardless of the instruction from the microcomputer 31 so that the energy tax relay 29 is not turned on. As a result, even if the relay 27 and / or the relay 28 through the ECU 11 (Microcomputer 31 ) is turned on, the pinion 21 and the electric motor 27 controlled, not to operate. That is, the starter 13 (Pinion 21 and electric motor 17 ) is due to the abnormality of the microcomputer 31 prevented from operating.

The microcomputer 31 the ECU 11 is programmed to the following control processing over time, as in 3 is shown execute. The microcomputer 31 First, performs starter control processing for setting the starter 13 for starting the engine, when the starter signal becomes active (eg, high level) due to a driver start operation (eg, the ignition key operation). This is as an initial starting condition (I) in 3 shown.

Specifically, the microcomputer causes 31 all transistors T1 and T2 of the ECU 11 and the transistor T3 of the ECU 12 to show the OFF states. As described above, the microcomputer 31 the microcomputer 41 the ECU 12 through communication with the microcomputer 41 on, the transistor T3 to control, on and off.

Should the starter 13 be started, the microcomputer turns off 31 the transistor T3 and the transistor T1, so that the power control relay 29 and the pinion control relay 27 be turned on to the coil 23a to supply electricity. Thus, the pinion 21 put to the sprocket 25 intervene. The microcomputer 31 further turns on the transistor T2 to the electric motor control relay 28 turn. The current becomes the coil 19a provided. Is the electromagnetic switch 19 thus turned on, the current flows from the battery 15 to the electric motor 17 , The electric motor 17 generates the rotational force and the pinion 21 rotates the gear 25 (that is, the electric motor is started). When the internal combustion engine is started, fuel and ignition are provided in the internal combustion engine under the control of another ECU (not shown) provided for controlling the internal combustion engine. In case the engine is a diesel engine, no ignition is necessary and thus only fuel is provided. The ECU 11 can be programmed to perform this engine control as well.

After determining that the internal combustion engine has achieved complete combustion (cranking has been completed and the engine has been successfully started), the microcomputer switches 31 the three transistors T1 to T3 off and switches the three relays 27 to 29 back to the OFF states. Thus, the power supply to the electric motor 17 stopped and the pinion is returned to the Ausgangsbeziehungsweise to the initial position at which the pinion 21 from the sprocket 25 is disengaged and no longer in the sprocket 25 intervenes. The microcomputer 31 calculates an engine rotation speed from the rotation signal and checks whether the engine has achieved the complete combustion based on the calculated engine rotation speed.

The starter control processing (starter control processing) is performed as described above. When the engine is in operation, it is referred to as an engine operating state (II) in FIG 3 designated. During engine operation, the microcomputer checks 13 whether a predetermined automatic stop condition is satisfied. When satisfied, the microcomputer stops 13 automatically the internal combustion engine by disconnecting the fuel injection into the internal combustion engine or interrupting an intake air supply to the internal combustion engine. Thus, when the internal combustion engine is automatically stopped, it is called an idling stop state (III) in FIG 3 designated. The automatic predetermined automatic stop condition is defined to satisfy one of the following conditions:
the battery voltage VB is equal to or greater than a predetermined value;
the travel speed is lower than a predetermined value;
the absolute value of the brake negative pressure is equal to or greater than a predetermined value;
the brake pedal is depressed;
the shift position is at the neutral position or the shift position is other than the neutral position and a clutch pedal is depressed;
the accelerator pedal is not pressed; and
more than a predetermined fixed time has elapsed after restarting the internal combustion engine after a previous automatic stop operation of the internal combustion engine.

During the idling stop state, when it is determined that a predetermined automatic start condition is satisfied, the starter control processing for restarting the engine is performed. This state is called a restart state (IV) in 3 designated.

For example, when the predetermined automatic restart condition is one of the following conditions is defined:
the brake pedal is released from the depressed state when the engine is stopped by the idling stop at a state where the shift position is other than the neutral position and the clutch is depressed;
the release of the clutch pedal (operation for reducing pressure on the clutch pedal for connecting the clutch) is started at a state where the shift position is other than the neutral position while the brake pedal is depressed; or
the shift position is changed from the neutral position to a position other than the neutral position (the clutch pedal is depressed) while the brake pedal is depressed.

Stop on the right in 3 indicates that the engine is stopped by the engine stop operation of a driver other than the idle state (III). In this case, the ignition system power supply in the vehicle is also turned off.

The microcomputer 31 the ECU 11 is programmed around the abnormality detection processing for detecting primarily abnormalities of the relays 27 to 29 in the engine operating condition (II), which is in 3 is shown. This abnormality detection processing may be performed immediately, for example, after the initial start operation of the internal combustion engine has been completed or performed periodically during operation of the internal combustion engine. It is also possible to detect the abnormality detection processing in the idling stop state of the internal combustion engine (III) in FIG 3 perform.

The abnormality detection processing will be described below. The output signals CM1 and CM2 are simply referred to as CM1 and CM2, respectively. The wire Lm connected to the terminal J3 is referred to as the monitoring path Lm. The resistance values of the coils 19a and 23a of the electromagnetic switch 19 and the pinion control solenoid 23 (about 1 Ω) of the starter 13 are sufficiently smaller than the resistance values r1 and r2 of the resistors R1 and R2 (about 10 KΩ). The resistance values of the coils 19a and 23a are negligible (assumed to be 0 Ω).

A principle of abnormality detection will be referred to 4 explained. If the three relays 27 to 29 are normal (no abnormality) and caused to be in the OFF state, the terminal voltage Vm is VB / 2, which corresponds to neither the ground voltage (ground line voltage 0V) nor the battery voltage VB, as described above. Thus, CM1 is low (Lo) and CM2 is high (Hi), as in a column "normal" in a row, an adjustment mode check ( 1 ) in 4 is specified. VB / 2 is smaller than the first threshold voltage Vth1 of the comparator 31 and higher than the second threshold voltage Vth2 of the comparator 52 ( 2 ).

If an ON fault occurs in the power control relay 29 on, that is, becomes the energy tax relay 29 set to the ON state, although all three relays 27 to 29 are switched off, the terminal voltage Vm is set to the battery voltage VB. The terminal voltage Vm is equal to the battery voltage VB (> Vth1). It should be noted that each relay is not is turned off, even if it is so controlled, if it has the ON error.

Thus, when the power control relay 29 has the ON fault under the condition that the relays 27 to 29 In order to turn off, both CM1 and CM2 are high as in a column (a) in the row of the set mode check (1) in FIG 4 is specified.

When a short circuit of the monitoring path Lm to the power source (short to the battery voltage VB) occurs, the terminal voltage Vm is the same as the battery voltage VB, as in the case where the power control relay has the ON fault. Thus, if the monitoring path Lm has the short circuit of energy, although the three relays 27 to 29 to be controlled, both CM1 and CM2 are high, as in a column (b) in the row of the set mode check ( 1 ) in 4 is specified.

That is, the power short of the monitor path Lm is detected as well as the ON error of the power control relay 29 , In the following description, as in a lower row in 4 is specified, both the ON error, the power control relay 29 and the energy short of the monitoring path Lm are classified as an abnormality [1].

If an ON fault occurs in the pinion control relay 27 the electric motor control relay 28 on, though all three relays 27 to 29 are controlled to turn off, the terminal voltage Vm is a voltage resulting from a division of the battery voltage VB by the resistor R1 and one of the two coils 19a and 23a results. As the resistance of the coil 19a . 23a is negligibly small with respect to the resistance r1 of the resistor R1, the terminal voltage Vm is substantially 0, which is lower than the second threshold voltage Vth2.

When the pinion control relay 27 or the electric motor control relay 28 has the ON fault, although the three relays 27 to 29 are controlled to the OFF states, CM1 and CM2 are both low as in columns (c) and (d) in the row of the set mode check (1) in FIG 4 is specified.

When a ground short of the monitoring path Lm (short to the ground line) occurs, the terminal voltage 0 V (Vth2) is similar to the case where one of the relays 27 and 28 has the ON error. When the monitoring path Lm has the ground short-circuit although the three relays 27 to 29 Both CM1 and CM2 are low, as in a column (e) in the row of the set mode check (1) in FIG 4 is specified.

That is, the ground short of the monitor path Lm is detected as well as the ON error of one of the relays 27 and 28 , In the following description, as in the lower row in 4 is specified, both the ON error of the relay and the ground short of the monitoring path Lm are classified as an abnormality [2].

Thus, the microcomputer detects 31 Distinguish the abnormalities [1] and [2] by the same based on the combination of CM1 and CM2, which are issued under the condition that all three relays 27 to 29 are controlled to turn off. That is, the abnormality [1] is detected when CM1 and CM2 are both high, and the abnormality [2] is detected when CM1 and CM2 are both low.

If an ON fault occurs in one of the relays 27 to 29 on, that is, one of the relays 27 to 29 is set to the OFF state, the terminal voltage Vm is VB / 2, which is the same as in the normal state (no abnormality). That is, the OFF error has no effect because the relays 27 to 29 are controlled to turn off. Even when the OFF error occurs, CM1 and CM2 are the same as those generated when the relays 27 to 29 be controlled to be in the off state and normal. CM1 is low and CM2 is high, as in columns (g), (h) and (i) in the row of the set mode check (1) in FIG 4 is specified.

This is also true if the audit trail Lm is corrupted (disconnected). That is, when a wire break occurs in the monitor path Lm, the terminal voltage Vm is continuously VB / 2 regardless of whether the relays 27 to 29 are controlled to turn on and off. If the line break occurs in the monitoring path Lm, with the relays being controlled to turn off, CM1 and CM2 have the same output value as at a normal time. CM1 is low and CM2 is high, as in a column (f) in the row of the set mode check (1) in FIG 4 is shown.

If only the pinion control relay 27 under the three relays 27 to 29 is on, the terminal voltage Vm is 0 V lower than the second threshold voltage Vth when the pinion positioning relay 27 is normal. CM1 and CM2 are both low, as in the column "normal" in an adjustment mode check ( 2 ) in 4 is specified.

Indicates the pinion control relay 27 OFF error, the pinion control relay switches 27 not actually one, even just the pinion relay 27 under the three relays 27 to 29 is controlled to turn on. Similar to the case of turning off the three relays 27 to 29 is the terminal voltage Vm VB / 2. As a result, CM1 is low and CM2 is high, as in column (h) in the set mode check (2) in FIG 4 is specified. It should be noted that even if a relay is controlled to turn on, in some cases it can not be turned on.

The microcomputer 31 can thus the OFF error of the pinion positioning relay 27 under the three relays 27 to 29 based on CM1 and CM2, which are generated when only the pinion positioning relay 27 is controlled to turn on.

If only the electric motor control relay 28 under the three relays 27 to 29 is on, the terminal voltage Vm is 0V when the electric motor control relay 28 is normal. CM1 and CM2 are both low, as in the "normal" column in a control mode check (3) in FIG 4 is shown.

Indicates the electric motor control relay 28 OFF fault, the electric motor control relay switches 28 not actually, even if only the electric motor control relay 28 under the three relays 27 to 29 is controlled, turn on. The terminal voltage Vm is VB / 2. As a result, CM1 is low and CM2 is high, as in column (i) in the set mode check (3) in FIG 4 is shown.

The microcomputer 31 can thus the OFF error of the electric motor control relay 28 under the three relays 27 to 29 based on CM1 and CM2, which are generated only when the electric motor control relay is controlled to turn on.

If only the energy tax relay 29 under the three relays 27 to 29 is on, the terminal voltage Vm is higher by VB than the first threshold Vth1 when the power control relay 29 is normal. CM1 and CM2 are both high, as in the column "normal" in a control mode check ( 4 ) in 4 is specified.

Indicates the power control relay 29 OFF error, the power control relay turns off 29 not actually one, even if only the energy tax relay 29 under the three relays 27 to 29 is controlled, turn on. The terminal voltage Vm is VB / 2. Thus, CM1 is low and CM2 is high, as in a column (g) in the set mode check (4) in FIG 4 is shown.

The microcomputer 31 can thus the OFF error of the electric motor control relay 28 under the three relays 27 to 29 based on CM1 and CM2, which are generated only when the electric motor control relay 28 is controlled, turn on.

If the monitoring path Lm is broken, the terminal voltage Vm is continuously set to VB / 2 as described above. In this case, as in the column (f) in each row of the check setting modes (2) to (4) in FIG 4 CM1 is low and CM2 is high when one of the three relays 27 to 29 is controlled, turn on. For this reason one comes to the following conclusion.

CM1 is low and CM2 is high, if only the pinion control relay 27 under the three relays 27 to 29 is controlled to turn on, it can be determined that the pinion control relay 27 is abnormal and has the OFF error. However, the monitoring path Lm is also likely to be damaged. or broken. Similarly, if CM1 is low and CM2 is high, if only the electric motor control relay 28 under the three relays 27 to 29 is controlled, it can be determined that the electric motor control relay 28 is abnormal and has the OFF error. However, it is also likely that the monitoring path Lm is damaged. Further, if CM1 is low and CM2 is high, if only the pinion positioning relay 27 under the three relays 27 to 29 is controlled to turn on, it can be determined that the pinion control relay 27 is abnormal and has the OFF error. However, it is also likely that the monitoring path Lm is broken.

The wire break of the monitoring path Lm may be considered the OFF fault of one of the relays 27 to 29 be detected without him from the OFF error of the relay 27 to 29 to distinguish. However, the line break of the monitor path Lm may be from the OFF error of one of the relays 19 as will be distinguished below.

It is assumed that the pinion control relay 27 has the OFF error, while the monitoring path Lm has no wire break or line break. Are the relays 28 and 29 except for the pinion control relay 27 When CM1 and CM2 are turned on, CM1 and CM2 remain the same as the normal case, as in the column (h) in the rows of the check setting modes (3) and (4) in FIG 4 is specified. That is, CM1 and CM2 do not become low or high.

It is also assumed that the electric motor control relay 28 has the OFF error, while the monitoring path Lm has no line break. Be the relays 27 and 29 with the exception of the electric motor control relay 28 turned on, CM1 and CM2 remain the same as in the normal case, as in column (i) in the rows of check setting modes (2) and (4) in FIG 4 is specified. That is, CM1 and CM2 do not become low or high.

It is also assumed that the energy tax relay 29 has the OFF error, while the monitoring path Lm has no line break. Are the relays 27 and 28 with the exception of the energy tax relay 29 turned on, CM1 and CM2 remain equal to the normal case as in the column (g) in the rows of the check setting modes (2) and (3) in FIG 4 is shown. That is, CM1 and CM2 do not become low or high.

For this reason, the microcomputer checks 31 CM1 and CM2 every time the pinion gear relays 27 . 28 or 29 be turned on one by one. CM1 is low and CM2 high in just one of these three cases where the relays 27 . 28 and 29 are turned on, becomes one of the relays 27 to 29 , which has turned on and caused CM1 and CM2 to go low and high, determines to have the OFF error. If CM1 is low and CM2 is high in one of the cases, and if CM1 and CM2 are the same as the normal time in the other two cases, the relay that has been turned on and caused CM1 and CM2 to go low and high determines the OUTPUT. To have errors. If CM1 is low and CM2 is high in at least two of the three cases, it can be determined that the relays have no fault, but the monitoring path Lm has the line break.

No current flows to the coils 23a and 19a if not the energy tax relay 29 and at least one of the relays 27 and 29 are turned on at the same time. The ignition 13 is thus not unnecessarily controlled to operate in the case where any abnormality is detected.

As in columns (a) and (b) in the rows of checkpoint modes (2) to (4) in 4 2, CM1 and CM2 are both high in either case in one of the three relays 27 to 29 is on when the power control relay 29 has the ON fault or the monitoring path Lm has the short circuit. This is because the terminal voltage Vm is the same as the battery voltage VB. As in the column (e) in the rows of the check setting modes (2) to (4) in FIG 4 In any case, CM1 and CM2 are one of the three relays 27 to 29 is on, low, when the monitoring path Lm has the ground short. This is because the terminal voltage Vm is 0V. If the ON fault occurs in the sprocket control relay or the electric motor control relay 28 on, CM1 and CM2 vary depending on the states of the relays 27 to 29 , as in columns (c) and (d) in the rows of check-setting modes (2) to (4) in FIG 4 is shown. That is, if that energy tax relay 29 is turned on, the terminal voltage Vm is the same as the battery voltage VB, and thereby CM1 and CM2 are both high. Is one of the relays 27 and 28 switched on, the terminal voltage Vm is 0 V and thus both CM1 and CM2 are low.

The microcomputer 31 is programmed to perform the fail - safe processing in 5 from the above-described detection of the abnormality. As in the bottom row in the table of 4 and in a table of 5 1, abnormalities are classified into six abnormalities [1] to [6] including the above-described abnormalities [1] and [2]. The line break of the monitoring path Lm is classified as an abnormality [3]. The OFF error of the power control relay 29 is classified as an abnormality [4]. The OFF error of the pinion control relay 27 is classified as an abnormality [5]. The OFF fault of the electric motor control relay 28 is classified as an abnormality [6].

As in 5 is shown when the microcomputer 31 detects the abnormality [1], it performs the processing of a user warning (warning to a vehicle user) that is processing for supplying the vehicle user with a warning indicating that a starter circuit is short-circuited to the power source. It further stores in a nonvolatile memory or the like (in 5 not shown) abnormality information indicating that the abnormality [1] exists and performs processing for prohibiting the idling stop operation (automatic engine stop operation).

As the processing for providing the vehicle user with the warning, a message indicating the content of the warning may be displayed on a display device, outputted by a sound from a speaker, or indicated by the lights of a warning light indicating the content of the warning ,

As the processing for inhibiting the idling stop operation, an idling stop prevention flag may be set (set to 1). That is, the computer 1 does not check whether the automatic stop condition is satisfied during engine operation, or performs processing for stopping the engine even if the automatic stop condition is satisfied.

The idling stop operation is prohibited for the following reasons when the abnormality [1] is detected. It is possible to power or no power to the coils 23a and 19a by switching on or off the relays 27 and 28 to control (that is, control of the starter 13 ). However, the relays can 27 and 28 who are operating normally, as well at this time fail and a current to the coil 23a or to the coil 19a allow unnecessarily. That is, the pinion control solenoid 23 or the electromagnetic switch 19 can be made to operate unnecessarily. As a result, the pinion 21 or the electric motor 17 in order to operate unnecessarily and an abnormality of necessary operations increases in the starter 13 at. Will the pinion 21 When asked to operate, it moves to a position where it is in the sprocket 25 engages (that is, it hits the sprocket 25 ).

By prohibiting the idling stop operation from the detection of the abnormality [1], the number of times, the starter and the starter respectively 13 is put, reduced and the relays 27 and 28 who are operating normally are protected from falling back into the ON fault.

The microcomputer 31 detects the abnormality [1] while setting the three relays 27 to 29 to switch off. Captures the microcomputer 31 the abnormality [1], it does not execute the abnormality detection processing by turning on one of the relays 27 to 29 is carried out. This abnormality detection processing is for detecting the OFF error in the relay 27 to 29 and the line break in the monitoring path Lm and becomes S180 to S340 in FIG 6 as described later.

Will the pinion control relay 27 or the electric motor control relay 28 turned on while the abnormality [1] is present becomes the coil 23a or the coil 19a unnecessarily supplied with the power that is effective, the pinion control solenoid 23 and the electromagnetic switch 19 turn. Thus, the unnecessary power supply is avoided by not performing S180 to S340.

The abnormality [1] is detected when CM1 and CM2 generated while the three relays 27 to 29 are off, both are high, as in the row of the control mode check (1) in 4 is shown. In this case, the monitoring path Lm has no line break. Further, it is not possible to obtain a correct detection result (that is, CM1 and CM2 are both high and different from a combination of CM1 (low) and CM2 (high), which is the OFF error in the relays 27 to 29 indicates) for detecting the OFF error of the relays 27 to 29 to gain even if the relays 27 to 29 be turned on one by one.

Captures the microcomputer 31 the abnormality [2], as processing of the user warning (warning of the vehicle user), performs processing for supplying the vehicle user with a warning indicating that the starter circuit is short-circuited with the ground. It also stores in the nonvolatile memory or the like (in FIG 5 not shown) abnormality information indicating that the abnormality [2] exists, and performs the processing for inhibiting the idling stop operation.

The idling stop operation is prohibited when the abnormality [2] is detected for the following reasons. It is possible to supply power to the coils 23a and 19a by switching on or off the power control relay 29 (that is, starter 13 Control) to allow or inhibit if the abnormality is the ON fault of the scribe relay 27 or the electric motor control relay 28 is. However, the power control relay can 29 that is operating normally, also fail at this time and a current to the coil 23a or to the coil 19a allow unnecessarily. That is, the pinion control solenoid 23 or the electromagnetic switch 19 can be made to operate unnecessarily. As a result, an abnormality of unnecessary operation or operations in the starter occurs 13 on.

By stopping the idle stop based on the detection of the abnormality [2], the number of times the starter is counted 13 is reduced, and the energy control relay 29 operating normally will be prevented from falling back into the ON error again.

The microcomputer 31 detects the abnormality [1] while setting the three relays 27 to 29 to turn off. Captures the microcomputer 31 the abnormality [1], it does not perform the abnormality detection processing by turning on any one of the relays 27 to 29 is carried out. This abnormality detection processing is for detecting the OFF error in the relay 27 to 29 and the line break in the monitoring path Lm and becomes S180 to S340 in FIG 6 as described below.

Will the pinion control relay 27 or the electric motor control relay 28 turned on while the abnormality [1] is present becomes the coil 23a or the coil 19a unnecessarily provided power, which is to turn on the pinion control solenoid 23 and the electromagnetic switch 19 is effective. Thus, this unnecessary power supply is avoided by not performing S180 to S340.

The abnormality [1] is detected when CM1 and CM2 generated while the three relay 27 to 29 are off, both are high, as in the row of the control mode check (1) in 4 is shown. In this case, the monitoring path Lm has no line break. Further, it is not possible to obtain a correct detection result (that is, CM1 and CM2 are both high and different from a combination of CM1 (low) and CM2 (high), which is the OFF error in the relays 27 to 29 indicates) with respect to the detection of the OFF error of the three relays 27 to 29 even if the relays 27 to 29 be turned on one by one.

Captures the microcomputer 31 the abnormality [2] executes as processing the user warning (warning to the vehicle user) that is processing for providing the user with a warning indicating that the starter circuit is shorted to the ground. It also stores in the nonvolatile memory or the like (in FIG 5 not shown) Abnormality information (indicating that the abnormality [2] exists, and performs the processing for prohibiting the idling stop operation.

The idling stop operation is prohibited when the abnormality [2] is detected for the following reasons. It is possible to power the coils 23a and 19a by switching on or off the power control relay 29 (that is, control of the starter 13 ) to allow or prohibit if the abnormality of the ON fault of the pinion relay 27 or the electric motor control relay 28 is. However, the power control relay can 29 that operates normally, as well at this time fail and unnecessarily a current to the coil 23a or to the coil 19a allow. That is, the pinion control solenoid 23 or the electromagnetic switch 19 can be made to operate unnecessarily. As a result, an abnormality of unnecessary operation occurs in the starter.

By stopping the idling stop from the detection of the abnormality [2], the number of times the starter becomes 13 is set or operated is reduced and the energy tax relay 29 operating normally will be prevented from falling back into the ON error again.

When starting or starting the engine, the pinion must 21 and the electric motor 17 be sequentially controlled so that the pinion 21 is moved first and then the electric motor 17 is made or operated. Is indistinguishable, whether the pinion relay 27 or the electric motor control relay 28 has the ON fault, although the electric motor control relay 28 actually has the ON fault, the above required control sequence can not be performed. If the abnormality that is actually present is the ground short of the monitoring path Lm of the abnormality [2], the line is 16 the battery voltage VB shorted to the ground line when the power control relay 29 is turned on to the starter 13 to operate. Consequently, for example, a fuse in the line 16 run away. To avoid this problem will be the number of times the starter 13 is reduced by inhibiting the idling stop when the abnormality [2] is detected.

The microcomputer 31 detects the abnormality [2] while controlling the three relays 27 to 29 off. Captures the microcomputer 31 the abnormality [2], it does not perform the abnormality detection processing by turning on any of the three relays 27 to 29 is carried out. This abnormality detection processing is for detecting the OFF error in the relay 27 to 29 and the line break in the monitoring path Lm and becomes S180 to S340 in FIG 6 carried out.

The abnormality present is the ON fault of the pinion control relay 27 or the electric motor control relay 28 the abnormality [2], the above-described unnecessary power supply is caused when the power control relay 29 is turned on. Then, this unnecessary power supply is avoided by not performing S180 to S340.

The abnormality [2] is detected when CM1 and CM2, while the three relays 27 to 29 are off, both are low, as in the row of the set mode check (1) in 4 is shown. In this case, the monitoring path Lm has no line break. Further, it is not possible to obtain a correct detection result (that is, CM1 and CM2 differ from a combination of CM1 (low) and CM2 (high), which is the OFF error in the relays 27 to 29 indicates) for detecting the OFF error of the relays 27 to 29 to gain even if the relays 27 to 29 be turned on one by one. If the ground short of the monitor path Lm is present, it is not preferable for the power control relay 29 to turn on because the battery voltage VB is shorted to the ground (short circuit between the line 16 the battery voltage VB and the ground line).

If the microcomputer 31 detecting the abnormality [3] (line break of the monitoring path Lm), as processing, it performs the user warning processing for supplying the vehicle user with a warning indicating that the monitoring path (Lm) is broken. It also stores in the nonvolatile memory or the like (not shown in FIG 5 ) Abnormality information indicating that the abnormality [3] exists and carries the Processing for inhibiting idling stop by.

The idle stop when the abnormality [3] is detected is inhibited for the following reasons. In the case of detecting the abnormality [3], it is not possible to detect abnormalities except the abnormality of the monitoring path Lm. Furthermore, it is even more likely that the OFF fault is in any of the relays 27 to 29 is present. If any of the relays 27 to 29 the abnormality, it is not possible the starter 13 to operate or operate, to operate normally. When the engine is automatically stopped by the idling stop control operation under this condition, the engine is not automatically restarted and the vehicle can not travel. Preventing the idling stop operation prevents the vehicle from becoming incapable of driving in advance.

The microcomputer detects the abnormality [4] (OFF error of the power control relay 29 ), it performs as processing the user alert processing to provide the user with a warning indicating that the relay 29 has the OFF error. It also stores in the nonvolatile memory or the like (in FIG 5 not shown) abnormality information indicating that the abnormality [4] exists, and performs the processing for inhibiting the idle stop operation.

Captures the microcomputer 31 the abnormality [5] (OFF error of pinion control relay 27 ), it performs as processing the user warning processing for supplying the vehicle user with a warning indicating that the pinion positioning relay 27 has the OFF error. It also stores in the nonvolatile memory or the like (in FIG 5 not shown) Abnormality information indicating that the abnormality [5] exists and performs the processing for inhibiting the idling stop operation.

Captures the microcomputer 31 the abnormality [6] (OFF error of the electric motor control relay 28 ), it performs as processing the user alert processing for providing the user with a warning indicating that the electric motor control relay 28 has the OFF error. It also stores in the nonvolatile memory or the like (in FIG 5 not shown) Abnormality information indicating that the abnormality [4] exists and performs the idling stop prohibition processing.

The idling stop is prohibited in the case of the abnormalities [4] to [6] for the reason that any one of the relays 27 to 29 failed to turn on the starter 13 can not be made or operated to operate and the vehicle can not drive.

The abnormality detection processing that the microcomputer 31 will be explained in detail with reference to the flowcharts shown in 6 and 7 are shown. As described above, the abnormality detection processing shown in FIG 6 is shown immediately after the initial starting operation of the internal combustion engine is completed or performed periodically during engine operation. All flags each of which is set to "1" indicating ON in this detection processing are reset to "0" indicating OFF by initialization processing (not shown) which is executed, for example, at the time of initialization of the microcomputer 31 ,

According to 6 represents the microcomputer 31 First, at S110, the three relays 27 to 29 to turn off to realize the control mode check ( 1 ), which is in 4 is shown.

That is, the microcomputer 31 switches the relays 27 and 28 by outputting the control signals for the transistors T1 and T2 in the non-active level, which turns off the transistor, and turns off the transistors T1 and T2. The microcomputer 31 switches the power control relay 29 by issuing the instruction to the microcomputer 41 the ECU 12 to turn off the transistor T3. The relays 27 to 29 become normal in the OFF state by the control processing of the starter 13 controlled during engine operation and during engine operation, respectively.

At S120, the microcomputer attains 31 the outputs CM1 and CM2 of the comparators 51 and 52 and checks if CM1 is low (Lo) and CM2 high (Hi). If CM1 is not low or CM2 is not high (S120: NO), it is likely that the abnormality [1] or [2] is present (as in the row of the control mode check (FIG. 1 ) is shown). Then the microcomputer leads 31 S130 for determining what abnormality exists.

At S130, the microcomputer checks 31 whether CM1 and CM2 are high. If CM1 and CM2 are high, the microcomputer determines 31 in that the abnormality [1] exists and executes S140. At S140 puts the microcomputer 31 set a flag F1 to "1" (ON) to indicate the detection of the abnormality [1], and then execute S350.

If CM1 or CM2 are not high at S130, the microcomputer checks 31 at S150, if CM1 and CM2 are low. If CM1 and CM2 are low, the microcomputer determines 31 , that the Abnormality [2] is present and executes S160. At S160 puts the microcomputer 31 a flag F2 "1" (ON) to indicate the detection of the abnormality [1] and then executes S350.

If CM1 or CM2 is not low at S150, the microcomputer determines 31 in that a diagnostic circuit (by the resistors R1, R2 and the voltage monitoring circuit 50 provided) for detecting the abnormalities [1] to [6] having abnormality, and executes S170. At S170 is the microcomputer 31 a flag Fer is fixed at "1" (ON) to indicate the detection of the abnormality of the diagnosis circuit, and then executes S350.

If the check result at S150 is NO, the combination of CM1 and CM2 that is generated corresponds to three relays 27 to 29 in the OFF states, not one of the combinations that are in the row of the set mode check (1) in 4 are indicated. Accordingly, the microcomputer determines 31 in that the diagnostic circuit has the abnormality.

If CM1 is low and CM2 is high at S120, it is normal or likely that one of the abnormalities [3] to [6] is present (as in the row of the control mode check (1) in FIG 4 is specified). The microcomputer 31 therefore executes S180 and subsequent steps.

At S180 the microcomputer switches 31 only the pinion control relay 27 on to set the control mode check (2) in 4 is shown, while he is the relay 28 and 29 maintains in the OFF states. That is, the microcomputer 31 outputs the control signal for the transistor T1 in the active level, which turns on the transistor, so that the pinion positioning relay is turned on by turning on the transistor T1.

At S190, the microcomputer attains 31 the outputs CM1 and CM2 of the comparators 51 and 52 and checks if CM1 and CM2 are low. If CM1 or CM2 are not low (S190: NO), the microcomputer determines 31 in that it is at least not normal and executes S200.

At S200, the microcomputer checks 31 whether CM1 is low and CM2 is high. If CM1 is low and CM2 is high, one of the abnormalities [3] and [5] is present (as in the control mode check (2) in FIG 4 is specified). The microcomputer 31 At S210, a flag F3 indicating that the abnormality is detected [3] and a flag F5 indicating that the abnormality [5] is detected are set to "1" (ON), and then S230 is executed. The microcomputer 31 determines which of the abnormalities [3] and [5] is present.

If CM1 is not low or CM2 is not high at S200, the microcomputer determines 31 in that the diagnostic circuit has the abnormality and executes S220. The microcomputer 31 sets flag Fer to "1" at S220 in the same manner as at S170, and then executes S350.

At this time, the check result S120 is YES, and it is confirmed that the abnormality [1] is not present. The combination of CM1 and CM2 never becomes the combination where CM1 and CM2 are high. It is only possible that CM1 and CM2 are high, or that CM1 is low and CM2 is high (as in the series of verification mode (2) in FIG 4 is shown). If the check result at S200 is NO, it is not possible for CM1 and CM2 to be low, nor for CM1 to be low and CM2 high. The microcomputer 31 determines therefore that the abnormality is present in the diagnostic circuit.

If CM1 and CM2 are low at S190, the microcomputer will run 31 S230 off. In this case (S190: YES), it is likely that there is no abnormality or that any of the abnormalities [4] and [6] exist.

At S230 the microcomputer switches 31 the pinion control relay 27 off and turns off the electric motor control relay 28 on to set the control mode check (3) in 4 is shown to realize. That is, the microcomputer 31 outputs the control signal for the transistor T1 in the non-active level, which turns off the transistor, so that the pinion control relay 27 is turned off by turning off the transistor T1. The microcomputer 31 outputs the control signal for the transistor T2 in the active level, which turns on the transistor, so that the electric motor control relay 28 is turned on by turning on the transistor T2. Thus, only the electric motor control relay 28 under the relay 27 to 29 switched on.

At S240, the microcomputer attains 31 the outputs CM1 and Cm2 of the comparators 51 and 52 and checks if CM1 and CM2 are low. If CM1 or Cm2 are not low (S240: NO), the microcomputer determines 31 that is at least not normal and performs S250.

At S250, the microcomputer checks 31 whether CM1 is low and CM2 is high. If CM1 is low and CM2 is high, any of the abnormalities [3] and [6] are present (as in the control mode check (3) in FIG 4 is specified). The microcomputer 31 At S260, the flag F3 indicates that the detection indicates the abnormality [3] and sets a flag F6 indicating the detection of the abnormality [6] to "1" (ON), and then executes S270. The microcomputer 31 determines which of the abnormalities [3] and [6] are present in the following steps.

If CM1 is not low or CM2 is not high on S250, the microcomputer determines 31 in that the diagnostic circuit has the abnormality and performs S220. The microcomputer 31 sets flag Fer to "1" at S220 and then executes S350.

In a similar manner as when determining NO at S200, it is determined that the abnormality [1] is not present at this moment. The combination of CM1 and CM2 will never be the combination that CM1 and CM2 are high. It is only possible that CM1 and CM2 are low, or that CM1 is low and CM2 is high (as in the row of the set mode check (3) in FIG 4 specify). If the check result at S250 is NO, it is not possible for CM1 and CM2 to be low, nor for CM1 to be low and CM2 high. The microcomputer 31 determines therefore that the abnormality is present in the diagnostic circuit.

If CM1 and CM2 are low at S240, the microcomputer will run 31 S270 off. In this case (S240: YES), there is likely to be no abnormality or any of the abnormalities [4] and [5] is present.

At S270 the microcomputer switches 31 the electric motor control relay 28 and turns off the power control relay 29 on to set the mode check ( 4 ) to realize that in 4 shown. That is, the microcomputer 31 outputs the control signal for the transistor T2 in the non-active level, which turns off the transistor, so that the pinion control relay 28 is turned off by turning off the transistor T2. The microcomputer 31 gives the instruction to the microcomputer 41 the ECU 12 out to the energy tax relay 29 Turn on by turning on the transistor T3. Thus, only the power control relay 29 under the relays 27 to 29 switched on.

At S280, the microcomputer attains 31 the outputs CM1 and CM2 of the comparators 51 and 52 and checks if CM1 and CM2 are high. If CM1 or CM2 is not high (S280: NO), the microcomputer determines 31 in that it is at least not normal and executes S290.

At S290, the microcomputer checks if CM1 is low and CM2 is high. If CM1 is low and CM2 is high, then any of the abnormalities [3] and [4] are present (as in the row of the control mode check (4) in FIG 4 is shown). The microcomputer 31 S300 executes to determine which of the abnormalities [3] and [4] exists.

At S300, the microcomputer checks 31 Whether the flag F3 is "1". If the flag F3 is "1", the microcomputer determines 31 in that the abnormality [3] of the abnormalities [3] and [4] is present. The microcomputer 31 resets flags F5 and F6 to "0" at S310. The microcomputer 31 then runs S350.

That is, in this case, the flag F3 is set to "1" in S210 or S260 (possible in both steps). Thus, CM1 is low and CM2 is high, not just when only the power control relay 29 under the relays 27 to 29 is on, but also if at least one of only the pinion control relay 27 and only the electric motor control relay 28 (probably both) is on. As described above, the combination that CM1 is low and CM2 is high is generated in at least two cases of three cases involving the three relays 27 to 29 be turned on one after the other. The microcomputer 31 determines that is not the abnormality [4] (OFF error) of the power control relay 29 but the abnormality [3] (line break of the monitoring path Lm) is present, as in column (f) in the 4 is shown.

If the abnormality [3] is present, the abnormalities [5] or [6] are absent. At S310, the microcomputer sets 31 therefore, the flags F5 and F6 are set to "0", which are set to "1" at S210 and S2560. That is, it is not possible to determine which of the abnormalities [3] and [5] is present at S210 and to determine which of the abnormalities [3] and [6] is present at S260. However, it is determined at S310 that it is the abnormality [3] that exists.

If the flag F3 is not "1" at S300, the microcomputer determines 31 that it is not the abnormality [3] but the abnormality [4] that exists. The microcomputer 31 sets the flag F4 to "1" (ON) at S320, indicating detection of the abnormality [4]. The microcomputer 31 then runs S350.

That is, in this case CM1 is high or CM2 is low, even if the relays 27 and 28 from the relays 27 to 29 are turned on. CM1 is low and CM2 is high only when the power control relay 29 is turned on. The microcomputer 31 determines that it is not the abnormality [3] but the abnormality [4] that exists as shown in the column (g) in FIG 4 is shown.

By checking CM1 and CM2 by turning on the three relays 27 to 29 successively, as described above, the microcomputer determines 31 in that the relay (energy control relay 29 in this example), which is turned on when CM1 is low and CM2 is high, has the OFF error when the check result confirms that CM1 and CM2 are high in only one of the three cases.

If CM1 is not low or CM2 is not high in S290, the microcomputer determines 31 in that the diagnostic circuit has the abnormality. Of the microcomputer 31 sets the flag Fer to "1" at S220 and then executes S350.

That is, in this case, the check result at S120 is YES, and it is confirmed that the abnormality [2] is not present. Thus, CM1 and CM2 do not result in the combination that CM1 and CM2 are low. CM1 and CM2 should result in the combination that CM1 and CM2 are high, or in the combination that CM1 is low and CM2 high (as in the row of the control mode check (4) in FIG 4 shown). If the check result at S290 is NO, it does not mean that CM1 and CM2 are both high, nor is CM1 low and CM2 high. The microcomputer 31 thus determines that the diagnostic circuit has the abnormality.

If CM1 and CM2 are high at S280, the microcomputer will run 31 S330 off. In this case, it is possible (S280: YES) that there is no abnormality or any of the abnormalities [5] and [6].

The microcomputer 31 checks at S330 whether the flag F5 or F6 is "1". If the flag F5 or F6 is "1", the microcomputer determines 31 in that the abnormality whose flag is "1" exists. That is, when the flag F5 is "1", the microcomputer determines 31 in that the abnormality [5] is present. If the flag F6 is "1", the microcomputer determines 31 in that the abnormality [6] is present. The microcomputer 31 resets the flag F3 to "0" at S340 and executes S350.

The flag F5 is thus set to "1" at S210, and the flag F6 is set to "1" at S260. However, in S210, it is not possible to determine which of the abnormalities [5] and [6] is present. Similarly, in S260, it is not possible to determine which of the abnormalities [3] and [6] is present. For this reason, the flag F3 is also set to "1".

It is determined at S340 that the check result at S280 is YES, and it is confirmed that CM1 and CM2 are both high (same as normal) when only the power control relay 29 from the relays 27 to 29 is turned on. It is not the abnormality [3] but either the abnormality [5] or the abnormality [6] that exists. Because of this, the microcomputer continues 31 at S340, the flag F3 is set to "0" and keeps the flag F5 or F6 set to "1" as it is.

As described above, when CM1 is low and CM2 is high, if only the pinion setting relay of the three relays 27 to 29 is turned on, the flag F3 and the flag F5 are set to "1" (from S200: YES to S210). Both CM1 and CM2 are high (S280: YES) similar to the normal case (no abnormality) when only the power control relay 29 is turned on, the flag F3 is reset to "0" (S340), and only the flag F5 remains at "1". Similarly, if CM1 is low and CM2 is high, if only the electric motor control relay 28 from the three relays 27 to 29 is turned on, the flag F3 and the flag F6 are set to "1" (from S250: YES to S260). Similar to the normal case (no abnormality), CM1 and CM2 are both high (S280: YES) when only the power control relay 29 is turned on, the flag F3 is set to "0" (S340), and only the flag F6 remains at "1".

The microcomputer 31 checks CM1 and CM2 by switching on the three relays 27 to 29 one by one, as described above. The microcomputer 31 determines that the relay (in this example pinion relay 27 or electric motor control relay 28 ), which is turned on when CM1 is low and CM2 is high, has the OFF error when the check result confirms that CM1 is low and CM2 is high in one of the three cases, and CM1 and CM2 are the same logic level in the other case normal case.

If both of the flags F5 and F6 are not "1" at S330 (S330: NO), the microcomputer determines 31 in that there is no abnormality (that is, normal) and executes S350.

At S350 leads the microcomputer 31 same processing as S110 to turn off the three relays 27 to 29 by. The microcomputer 31 then performs failover processing S360, which is detailed in 7 is shown.

According to 7 the microcomputer checks 31 at S410, first, if the flag F1 is "1". If the flag F1 is "1", the microcomputer performs 31 S420. At S420 leads the microcomputer 31 the processing for issuing the warning indicating that the starter circuit has the power short-circuit as the user warning in the case of detecting the abnormality [1]. The microcomputer 31 then executes S550.

If the flag F1 is not "1" at S410, the microcomputer checks 31 at S430, if the flag F2 is "1". If the flag F2 is "1", the microcomputer performs 31 S440 off. At S440 leads the microcomputer 31 the processing for issuing the warning indicating that the starter circuit has the ground short circuit as the user warning in the case of detecting the abnormality [2]. The microcomputer 31 then executes S550.

If the flag F2 is not "1" at S430, the microcomputer checks 31 at S450, if the flag F3 is "1". If the flag F3 is "1", the microcomputer S460 executes. At S460 leads the microcomputer 31 the processing for issuing the warning indicating that the monitoring path Lm has the line break or the line damage as the user warning in the case of detecting the abnormality [3]. The microcomputer 31 then executes S550.

If the flag F3 is not "1" at S450, the microcomputer checks 31 at S470, if the flag F4 is "1". If the flag F4 is "1", the microcomputer performs 31 S480 off. At S480 leads the microcomputer 31 the processing for issuing the warning indicating that the power control relay 29 has the OFF error as the user warning in the case of detecting the abnormality [4]. The microcomputer 31 then executes S550.

If the flag F4 is not "1" at S470, the microcomputer checks 31 at S490, if the flag F5 is "1". If the flag F5 is "1", the microcomputer performs 31 S500 off. At S500, the microcomputer performs the processing for issuing the warning indicating that the pinion positioning relay 27 has the OFF error as the user warning in the case of detecting the abnormality [5]. The microcomputer 31 then executes S550.

If the flag F5 at S490 is not "1", the microcomputer checks 31 at S510, if the flag F6 is "1". If the flag F6 is "1", the microcomputer performs 31 S520 off. At S520 leads the microcomputer 31 the processing for issuing the warning indicating that the electric motor adjusting relay 28 has the OFF error as the user warning in case of detecting the abnormality [6]. The microcomputer 31 then executes S550.

If the flag F6 is not "1" at S510, the microcomputer checks 31 at S530, if the flag Fer is "1". If the flag Fer is "1", the microcomputer will run 31 S540 off. At S540, the microcomputer executes the processing for issuing the warning indicating that the diagnosis circuit has the abnormality as the user warning in case of detecting the abnormality of the diagnosis circuit. The microcomputer 31 then executes S550.

Thus, the microcomputer performs 31 S550, if any one of the flags F1 to F6 and Fer is "1" and the abnormality corresponding to the flag "1" is determined. At S550 leads the microcomputer 31 the processing for inhibiting the idling stop operation by. Specifically, the microcomputer sets 31 an idling stop flag as described above. The microcomputer 31 then terminates the fail-safe processing and thus also the abnormality detection processing.

In the failover processing, the in 7 is shown represents the microcomputer 31 the user warning corresponding to the detected abnormality is ready and inhibits the idling stop operation when any one of the abnormalities [1] to [6] or the abnormality of the diagnosis circuit is detected.

The idling stop operation becomes as above 5 FIG. 2 illustrates when any of the abnormalities [1] to [6] is detected. The idling stop operation is also inhibited when the abnormality of the diagnosis circuit is detected. This is because it is not possible to check if a circuit (power supply circuit for coils 19a and 23a ) for setting or operating the starter 13 is normal if the diagnostic circuit is abnormal, and thus it is not possible to use the starter 13 to operate in order to operate normally.

If it is determined at S530 that the flag Fer is not "1", the microcomputer determines 31 in that there is no abnormality, since all the flags F1 to F6 and Fer are "0", and terminates the fail-safe processing and the abnormality-detection processing as well as in FIG 6 are shown.

The microcomputer 31 in the other abnormality information memory processing, refers to the flags F1 to F6, and stores in the non-volatile memory or the like abnormality information (that is, a diagnosis code) indicating the presence of abnormality represented by the flag "1". The abnormality information thus stored in the nonvolatile memory is read out by a fault diagnosing means (for example, a scanning tool) connected to the ECU 11 is connectable to communication.

According to the starter control device, the two ECUs 11 and 12 and three relays 27 to 29 As described above, the spool becomes 23a not unnecessarily fed, unless both the power control relay 29 and the pinion control relay 27 that are connected in series with ON errors. Similarly, the coil becomes 19a not unnecessarily fed, unless both the power control relay 29 and the electric motor control relay 28 that are connected in series with ON errors.

That is, even if one of the two series-connected relays has the ON fault, the current flow becomes the coil 23a and 19a avoided unless the other of the two series-connected relays is not turned on. Thus, the abnormality becomes unnecessary operation of the pinion 21 or the electric motor 17 in the starter 13 avoided.

Because the ON error of each relay 27 to 29 can be detected, it is possible to advance the fail-safe processing by determining perform that coil 23a or the coil 19a will be fed unnecessarily and the starter 13 will be unnecessarily operated or made.

Specifically, if the ON error of any of the three relays 27 to 29 (Abnormality [1] or [2]), the idling stop operation is prohibited. By thus reducing the number of operations of the starter 13 , it is possible to prevent the relay operating normally from having the ON fault, thereby improving the reliability of the device.

Because the OFF error is every relay 27 to 29 can also be detected, the reliability of the starter noise can be further improved. Specifically, if the OFF error is one of the relays 27 to 29 (one of the abnormalities [4] to [6]), the idling stop operation is prohibited. It is thus possible to avoid that the internal combustion engine is no longer restartable and the vehicle is no longer movable.

When the OFF error of the relay 27 to 29 is detected, it is also possible to instruct a driver of the vehicle not to stop the engine as a measure, which is other than the idling stop operation and the operation of the starter 13 not necessary. As such a measure, a message may be sounded or displayed on a display to indicate that the engine should not be stopped. In the case of a vehicle in which an internal combustion engine is stopped when a start button switch is pressed down continuously, a predetermined time interval from continuous depression to stop the internal combustion engine may be changed to a longer interval. It is thus possible by this measure to avoid that the engine is stopped by the driver, and the vehicle is no longer mobile.

In the abnormality detection processing in FIG 6 when the abnormality [1] or the abnormality [2] is detected by S110 to S160 and the ON fault is detected by one of the relays 27 to 29 is detected, the processing of S180 to S340 for detecting the ON error of the relay 27 to 29 not executed. As a result, it is avoided, for example, that the relay 27 or 28 for abnormality detection is turned on while the power control relay 29 has the ON error. In addition, it avoids that the energy tax relay 29 for the abnormality detection while the relay has the ON error. By thus performing the abnormality detection processing as in 6 is shown, it is sure to avoid the coil 23a or the coil 19a is energized, otherwise the pinion control solenoid 23 or the electromagnetic switch 19 would activate.

In the first embodiment, the coil correspond 23a and the coil 19a electrical loads that the starter 13 to operate or operate. The ground voltage and the battery voltage VB correspond to a first potential and a second potential, respectively.

Regarding the coil 23a make up the energy tax relay 29 and the pinion control relay 27 Power supply switching means in a current path to the coil 23a to be provided. The energy tax relay 29 Forms energy-side switching means and the pinion control relay 27 also forms load-side switching means. Regarding the coil 19a , make the energy tax relay 29 and the electric motor control relay 28 Power supply switching means off, in a current path to the coil 19a to be provided. The energy tax relay 29 forms energy-side switching means and the electric motor control relay 28 forms load-side switching means.

The voltage monitoring unit 50 and the microcomputer 31 form abnormality detection means. The microcomputer 31 also forms idling stop control means. The resistor R2 forms a first resistive part and the resistor R1 forms a second resistive part.

Processing from S110 to S160 in 6 forms an OFF-positioning-period abnormality detection processing. Processing from S180 to S210 in 6 forms an ON-time-period abnormality detection processing, wherein the pinion-adjusting relay 27 is assumed to be a specific switching means. The processing of S230 to S260 in 6 forms ON-time-period abnormality detection processing, wherein the electric motor adjusting relay 28 as the specific switching means is assumed. Processing from S270 to S340 in 6 forms an ON-time-period abnormality detection processing, the power-control relay 29 as the specific switching means is assumed.

It is assumed that the coil 23a and the coil 19a the first electrical load and the second electrical load are the pinion actuating relay 27 and the electric motor control relay 28 , the first load-side switching means or the second load-side switching means form. Processing from S180 to S210 in 6 forms an ON-time-period abnormality detection processing for a first load-side switching means. The processing of S230 to S260 in 6 forms an ON-time-period abnormality detection processing for a second load-side switching means.

Although the line break or the line damage of the monitoring path Lm by distinguishing the same from the OFF error of the relay 27 to 29 in the abnormality detection processing in 6 is detected, it is possible, the line break of the monitoring path Lm from a part of the OFF error of the relay 27 to 29 capture. In this case, in the abnormality detection processing in FIG 6 the flag F3 may not be set to "1" in each of S210 and S260, and further, S300, S310, S330, and S340 may be omitted. If the check results for S280 and S290 are YES, S350 or S360 can be executed.

Second Embodiment

A second embodiment, in 8th is different from the first embodiment in the following points. The ignition 13 is configured such that an operation of engaging the pinion 21 in the sprocket 25 and the operation of the electric motor 17 are linked. That is, the pinion 21 and the electric motor 17 will not be independent of each other in this starter 13 provided or operated.

Specifically, if the coil 23a of the solenoid 23 is fed, not only the pinion 21 pushed out to the sprocket 25 but also the contacts 19b and 19c of the electromagnetic switch 19 are due to the electromagnetic force of feeding the coil 23a for conducting the battery 15 to the electric motor 17 shorted.

Thus, the coil becomes 19a which is provided in the first embodiment eliminates and the electric motor control relay 28 , that to power the coil 19a is provided in the first embodiment is also eliminated. The transistor T2 for switching on the electric motor control relay 28 in the first embodiment is also eliminated.

That is, in the second embodiment, the coil forms 23a an electrical load (electrical load for placing or operating the starter 13 for operating), which is both the pinion 21 as well as the electric motor 17 provides or operates. The pinion control relay 27 thus operates as a relay to set the pinion 21 and the electric motor 17 and thus as a starter relay for setting the starter 13 ,

In the second embodiment, the microcomputer 31 the ECU 11 configured to perform an abnormality detection operation based on operation states of the relays 27 . 29 and a combination of outputs CM1, CM2 of the comparators 51 . 52 perform. This operation appears in a table that is in 9 is shown summarized.

Compared with the table in 4 is shown in the first embodiment, the table in 9 no gaps with respect to the electric motor control relay 28 , no series regarding the control mode check (3) and no columns regarding (d) and (i). In the second embodiment, the abnormality [2] indicates the ON error of the pinion positioning relay 27 or the ground short of the monitoring path Lm. The abnormality [6] (OFF error of the electric motor control relay 28 ) is eliminated.

The microcomputer 31 is configured to detect an abnormality detection processing included in 10 instead of the abnormality detection processing of FIG 6 perform. The abnormality detection processing of 10 is different from the one in 6 in that the processing relating to the electric motor control relay 28 is eliminated. That is, the processing in 10 is different from the one in 6 as explained below.

For S115, instead of S110 ( 6 ) is executed, the microcomputer switches 31 the two relays 27 and 29 out. S230 to S260 ( 6 ) are eliminated. For S275, instead of S270 ( 6 ) is executed, the microcomputer switches 31 the pinion control relay 27 turned off at S180 and turns on the power control relay 29 one.

The flag F6 is not provided. For S315, instead of S310 ( 6 ) is executed, sets the microcomputer 31 only the flag F5 at "0". For S335 instead of S330 ( 6 ) is executed, the microcomputer checks 31 whether the flag F5 is "1".

For S335 instead of S350 ( 6 ) is executed, the microcomputer switches 31 the two relays 27 and 29 similar to S115. At S365, which is executed instead of S360, the microcomputer performs 31 the fail-safe processing in 11 is shown off.

The fail-safe processing of 11 differs only in the following points from the in 7 , The processing of S510 and S520 ( 7 ) is eliminated. Therefore, if the check result at S490 is NO, the microcomputer performs 31 S530 off.

Since the pinion control relay 27 As a starter relay in the second embodiment, it is possible to provide a warning to a driver indicating that the starter relay has the OFF error, executed at S500 when the flag F5 is "1".

The present invention is not limited to the embodiments described above, but may be implemented in other embodiments as exemplified.

The electric motor 17 can be assumed as an electrical load for the starter. In this case, the electromagnetic switch 19 assumed as the load-side switching means. A relay that has approximately the same power supply capacity as the electromagnetic switch 19 can, as the power-side switching means on the upstream side of the electromagnetic switch 19 in the power supply path of the electric motor 17 to be provided.

In the above-described embodiments, a low-potential side (ground voltage) is assumed to be the first potential. That is, a high-side actuating circuit or a high-side actuating circuit configuration is adapted so that the power supply switching means is provided at the high potential side of the electric load. However, the first potential may be considered to be on the high potential side of the power source. That is, a low-side setting circuit configuration may be adopted so as to provide the power supply switching means on the downstream side of the electric load.

Concretely, in 1 first ends of the coils 23a and 19a with the line 16 be connected to the battery voltage VB and the contact 29b of the energy tax relay 29 can be connected to the ground line. In this case, two current paths are formed. A path goes from the battery voltage VB to the ground line through the coil 23a , the pinion control relay 27 and the energy tax relay 29 , The other path goes from the battery VB to the ground line through the coil 19a , the electric motor control relay 28 and the energy tax relay 29 ,

At least one of the relays 27 to 29 can in one of the ECUs 11 and 12 be provided. In 1 can the contact 28a the electric motor control relay 28 with the line 16 the battery voltage VB be connected by a relay that is separate to the energy control relay 29 is provided without contact 29b of the energy tax relay 29 to be connected. That is, a set of two series-connected relays can be used for each of the coils 23a and 19a be provided.

The power supply switching means need not be a mechanical relay, but may also be a semiconductor switch such as a transistor. The ECUs 11 and 12 can be integrated in a single unit.

In summary, the invention relates to a solenoid for engaging a pinion of a starter in a ring gear of an internal combustion engine is supplied with a current which is provided by a battery voltage line by means of relays which are connected in series. An electromagnetic switch for actuating a motor of the starter is also supplied with a current supplied from the battery voltage line by the relay and a relay connected in series. An ECU detects a failure of the relays by monitoring a voltage of the path between the relay and the relays while putting the relays in the OFF states.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 2001-207942 A [0002]
• JP 11-30139A [0005, 0008]

Claims (8)

Starter control device for a vehicle that has an electrical load ( 19a . 23a ) for driving a starter ( 13 ) for starting a motor, wherein an end of the electrical load having a first potential, which is either a potential of a high potential side or a low potential side of a power source ( 15 ), wherein the starter control device comprises: a power supply switching means ( 27 . 28 . 29 ) provided in a current path formed between the other end of the electric load and a second potential that the other potential is from the high potential side and the low potential side of the power source, the power supply switching means being turned on, to provide a current to the electrical load, the power supply switching means ( 27 . 28 . 29 ) an energy-side switching means ( 29 ) and a load-side switching means ( 27 . 28 ), the power-side switching means ( 29 ) a couple of contacts ( 29a . 29b ), one of which is connected to the second potential, the load-side switching means ( 27 . 28 ) a couple of contacts ( 27b . 27c . 28b . 28c ), one of which is connected to a contact opposite to the other contact of the power-side switching means, and the other is connected to the other end of the electrical load; and an abnormality detecting means ( 31 . 50 ) for monitoring a voltage of an intermediate switch path (Lm) between the power-side switching means and the load-side switching means while controlling the power-side switching means and the load-side switching means in OFF states, and performing an OFF-timing abnormality detection processing for detecting an ON fault of one of the power-side switching means and the load-side switching means based on a monitored voltage. A starter control device according to claim 1, further comprising: an idling stop control means (12) 31 ) for stopping the internal combustion engine when a predetermined automatic stop condition is satisfied, and for starting the engine when a predetermined automatic start condition is met, wherein the power supply switching means ( 27 . 28 . 29 ) is turned on to drive the starter when the engine is restarted by the idling stop control means, and the abnormality detecting means (FIG. 31 . 50 prevents the idling stop control means from stopping the engine when the ON fault is detected by the power-side switching means or the load-side switching means. A starter control apparatus according to claim 1 or 2, wherein: said abnormality detecting means (15) 31 . 50 ) monitors the voltage of the intermediate switch path while keeping the specific switching means ( 27 . 28 . 29 ) that the power-side switching means or the load-side switching means is in the ON state and controls the other switching means except the specific switching means in the OFF state and detects an OFF error of the specific switching means based on the monitored voltage. A starter control apparatus according to claim 3, wherein: said abnormality detecting means (14) 31 . 50 ) performs ON-time-period abnormality detection processing by setting the power-side switching means and the load-side switching means to thereby detect the OFF-failure of the power-side switching means and the load-side switching means. A starter control apparatus according to claim 3 or 4, wherein said abnormality detecting means (14) 31 . 50 ) the ON-time-period abnormality detection processing stops when the ON-error is included by the power-side switching means or the load-side switching means by the OFF-time-period abnormality detection processing. A starter control device according to any one of claims 2 to 5, wherein: the power supply switching means is turned on to operate the starters when the engine is restarted by the idling stop control means; and the abnormality detecting means prohibits the idling stop control means from stopping the internal combustion engine when the OFF error is detected by the power-side switching means or the load-side switching means. A starter control device according to any one of claims 3 to 6, wherein: the electrical load ( 19a . 23a ) a first electrical load and a second electrical load ( 19a ), which are independently powered, and the starter is operated when both the first electrical load and the second electrical load are powered; the load-side switching means ( 27 . 28 ) a first load-side switching means ( 28 ) and a second load-side switching means ( 27 ) includes; the first load-side switching means ( 28 ) a couple of contacts ( 28b . 28c ), wherein one of the contacts is connected to a contact facing the second potential side of the power-side switching means, and the other contact is connected to a contact facing the first potential side of the electric load; the second load-side switching means ( 27 ) a couple of contacts ( 27b . 27c ), wherein a contact is connected to the contact, which is opposite to the second potential side of the power-side switching means, and the other contact is connected to a contact, which is opposite to the first potential side of the second electrical load; the abnormality detection means ( 31 . 50 ) as the ON-time-period abnormality detection processing in which the load-side switching means is set as the specific switching means performs ON-time-period abnormality detection processing for a first load-side switching means and ON-time-period abnormality detection processing for a second load-side switching means; the ON-time abnormality detection processing for a first load-side switching means monitors the voltage of the intermediate-switch path while controlling the first load-side switching means to turn on and controls the power-side switching means and the second load-side switching means to turn off, and an OFF failure of the first load-side switching means based on the monitored voltage detected; and the ON-time abnormality detection processing for a second load-side switching means monitors the voltage of the intermediate-switch path while controlling the second load-side switching means to turn on and controls the power-side switching means and the first load-side switching means to turn off, and based an OFF-fault of the second load-side switching means detected on the monitored voltage; and A starter control device according to any one of claims 1 to 7, further comprising: a first resistance part (R2) connected between the first potential and the intermediate switch path; and a second resistance part (R1) connected between the second potential and the intermediate switch path.

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