JP4719698B2 - Vehicle speed sensor failure diagnosis device for vehicle and cooling fan motor failure diagnosis device - Google Patents

Description

  The present invention relates to an engine control device, and more particularly to a vehicle speed sensor and a cooling fan motor failure diagnosis device for an engine control device including a vehicle speed sensor and an electric cooling fan.

  In a vehicle that is electronically controlled, a vehicle speed detection signal from a vehicle speed sensor is sent to a controller, and is used as one of elements for determining the control during exhaust gas recirculation control (EGR control) or the like. As is well known, the structure of the vehicle speed sensor is a combination of a rotating body having a protrusion and an electromagnetic pickup that extracts the passage of the protrusion as an electric signal. The electric signal from the electromagnetic pickup is sent to the controller. Reportedly.

  As a vehicle speed sensor failure diagnosis device for a vehicle speed sensor, for example, a vehicle speed sensor is provided for each of the front and rear wheels, and the difference between the output values of the vehicle speed sensors provided for each is compared with a set value. When the large state continues for a predetermined time, it is considered that the vehicle speed sensor whose output value is close to zero is determined as a failure (Patent Document 1). 2. Description of the Related Art Failure diagnosis devices that determine that a vehicle speed sensor is faulty when an output value from the vehicle speed sensor is below a set value for a predetermined time in an engine operating state that should be output from the vehicle speed sensor are well known.

  The cooling fan that cools the cooling water of the engine is driven by an electric motor. For example, when a disconnection or an electric motor fails, the cooling fan is not driven and the cooling water temperature rises and overheats. May stop. Therefore, in a cooling fan control device that controls the rotation of the cooling fan by supplying a drive control signal to the cooling fan motor, the terminal voltage detection means detects the terminal voltage of the cooling fan motor, and the drive control signal is sent to the cooling fan motor. When a change in the terminal voltage of the cooling fan motor is equal to or less than a predetermined reference value when the output is output, a failure diagnosis device that determines that the cooling fan motor has failed has been considered (Patent Document 2).

Japanese Patent No. 2802306 JP-A-8-284663

  However, exhaust regulations are becoming stricter year by year, and accordingly, there is a demand for improvement in failure detection accuracy for each part and function including sensors related to engine control, which causes engine exhaust gas levels to deteriorate. In the vehicle speed sensor failure diagnosis device disclosed in Patent Document 1, a vehicle speed sensor is provided for each of the front and rear wheels, and a plurality of vehicle speed sensors are required, resulting in an increase in cost. Further, in the failure diagnosis device that determines that the vehicle speed sensor is in failure when the state where the output value from the vehicle speed sensor is below the set value continues for a predetermined time in the operating state of the engine that should be output from the vehicle speed sensor, the function of the vehicle speed sensor It is difficult to diagnose a mechanical failure (for example, a failure such as a low output from a vehicle speed sensor with respect to an actual vehicle speed at a high vehicle speed).

  In the cooling fan motor failure diagnosis apparatus disclosed in Patent Document 2, a failure of the cooling fan motor due to disconnection can be diagnosed by looking at a change in the terminal voltage of the cooling fan motor. It is difficult to diagnose a functional failure only by changing the terminal voltage.

  By the way, the electric fan motor that cools the cooling water and the refrigerant of the air conditioner is rotated by the traveling wind force while the vehicle is traveling, and the current of the electric fan motor changes. Then, it has been found that there is a correlation between the current value of the electric fan motor and the vehicle speed, and the speed of the vehicle speed can be estimated from the current value of the electric fan motor.

  The present invention has been made in consideration of the above-described circumstances, and provides a vehicle speed sensor failure diagnosis device that can diagnose a functional failure of a vehicle speed sensor at a low cost without providing a plurality of vehicle speed sensors. It is an object of the present invention to provide a cooling fan motor failure diagnosis device that can diagnose a fixing failure such as disconnection and can diagnose a functional failure of an electric fan motor at low cost.

  In order to achieve the above object, a vehicle speed sensor failure diagnosis device for a vehicle according to the present invention includes a vehicle speed sensor that detects a vehicle speed, and an electric fan motor that cools cooling water and a refrigerant of an air conditioner. A current detecting means for detecting a current of the electric fan motor; an estimated vehicle speed grasping means for grasping an estimated vehicle speed based on a current value of the electric fan motor detected by the current detecting means; and the estimated vehicle speed grasping means. And a failure determination means for determining a failure of the vehicle speed sensor based on the estimated vehicle speed grasped in step 1 and the vehicle speed detected by the vehicle speed sensor.

  The vehicle speed sensor failure diagnosis device for a vehicle according to the present invention is characterized in that the estimated vehicle speed grasping means grasps the estimated vehicle speed based on a preset correlation between the current value of the electric fan motor and the vehicle speed.

  In the present invention, the fan of the electric fan motor that cools the cooling water and the refrigerant of the air conditioner is rotated by receiving the traveling wind force while the vehicle is running, and the electric fan motor current changes, and the current value of the electric fan motor It is based on the fact that the speed of the vehicle can be estimated by detecting the current value of the electric fan motor when the vehicle is running, and detecting it by a map or the like in which the correlation between the current value of the electric fan motor and the vehicle speed is set The estimated vehicle speed is determined based on the current value of the electric fan motor, and the estimated vehicle speed is compared with the vehicle speed detected by the vehicle speed sensor. Can be diagnosed with

  In addition, the vehicle speed sensor failure diagnosis apparatus for a vehicle according to the present invention includes learning means for the vehicle speed sensor failure diagnosis apparatus to learn an estimated vehicle speed in each driving region of the vehicle, and the learning means includes an estimated vehicle speed in the learned driving region. And an estimated vehicle speed grasped based on the current value detected by the current detecting means, the traveling environment of the vehicle is grasped.

  The present invention learns the estimated vehicle speed in each driving region of the vehicle, and uses the estimated vehicle speed learned in the driving region and the estimated vehicle speed based on the current value detected by the current detection means to determine the wind speed, wind direction, etc. where the vehicle is traveling The driving environment status of the vehicle can be grasped, and the reliability of the estimated vehicle speed can be known.

  Further, the vehicle speed sensor failure diagnosis apparatus for a vehicle according to the present invention is characterized in that the failure determination means determines whether or not to determine the failure of the vehicle speed sensor based on the traveling environment situation of the vehicle grasped by the learning means. In addition, when the reliability of the estimated vehicle speed based on the current value detected by the current detection means is low, the failure diagnosis of the vehicle speed sensor is not performed, so that the erroneous failure diagnosis can be reduced.

  An electric fan motor failure diagnosis device for a vehicle according to the present invention includes a vehicle speed sensor that detects a vehicle speed, and an electric fan motor that cools cooling water and a refrigerant of an air conditioner, and the electric fan motor failure diagnosis device includes the electric motor motor failure diagnosis device. Current detection means for detecting the current of the fan motor, estimated current value grasping means for grasping the estimated current value of the electric fan motor based on the vehicle speed of the vehicle speed sensor, and the estimated current value grasped by the estimated current value grasping means And failure determination means for determining failure of the electric fan motor based on the current value of the electric fan motor detected by the current detection means.

  The electric fan motor failure diagnosis apparatus for a vehicle according to the present invention is characterized in that the estimated current value grasping means grasps the estimated current value based on a preset correlation between the current value of the electric fan motor and the vehicle speed. Yes.

  The present invention detects a vehicle speed with a vehicle speed sensor, grasps an estimated current value of the electric fan motor based on the vehicle speed based on a map in which a correlation between the electric fan motor current value and the vehicle speed is set, and the like. By comparing the current value of the electric fan motor detected by the means with the estimated current value, it is possible to determine a functional failure of the electric fan motor.

  Further, the electric fan motor failure diagnosis apparatus for a vehicle according to the present invention includes learning means for learning the current value detected by the electric current detection means in each driving region of the electric fan motor failure diagnosis apparatus. Is characterized in that the running environment of the vehicle is grasped from the current value in the learned driving region and the current value detected by the current detecting means.

  The present invention learns the current value detected by the current detection means in each driving region of the vehicle, and uses the learned current value in the driving region and the current value detected by the current detection means to determine the wind speed of the place where the vehicle is traveling, Since the traveling environment such as the wind direction is grasped, the reliability of the current value detected by the current detecting means can be known.

  The electric fan motor failure diagnosis apparatus for a vehicle according to the present invention is characterized in that the failure determination means determines whether or not to determine the failure of the electric fan motor based on the traveling environment situation of the vehicle grasped by the learning means. When the current value of the electric fan motor detected by the current detection means is low when the driving environment is not normal, the failure diagnosis of the vehicle speed sensor is not performed, so that the erroneous failure diagnosis can be reduced.

  Furthermore, the electric fan motor failure diagnosis apparatus for a vehicle according to the present invention includes a vehicle speed sensor that detects a vehicle speed, and an electric fan motor that cools cooling water and a refrigerant of an air conditioner. A current detection means for detecting a current of the electric fan motor; and a failure determination means for determining a failure of the electric fan motor based on a change in the vehicle speed detected by the vehicle speed sensor and a current change detected by the current detection means. It is said.

  The present invention detects a vehicle speed by a vehicle speed sensor, detects a current of an electric fan motor that cools cooling water and a refrigerant of an air conditioner by a current detection means, and detects by a current detection means when a vehicle speed detected by the vehicle speed sensor changes. It is possible to determine a fixing failure such as disconnection of the electric fan motor by observing the change in current.

  A vehicle speed sensor failure diagnosis apparatus for a vehicle according to the present invention is estimated based on a vehicle speed sensor that detects a vehicle speed, a current detection unit that detects a current of an electric fan motor, and a current value of the electric fan motor detected by the current detection unit. An estimated vehicle speed grasping means for grasping the vehicle speed, detecting a current value of the electric fan motor when the vehicle travels, and grasping the estimated vehicle speed by the estimated vehicle speed grasping means based on the detected current value of the electric fan motor, By comparing the estimated estimated vehicle speed and the vehicle speed detected by the vehicle speed sensor, it is possible to diagnose a failure of the vehicle speed sensor with a simple configuration without providing a plurality of vehicle speed sensors.

  The vehicle cooling fan motor failure diagnosis apparatus according to the present invention includes a vehicle speed sensor that detects a vehicle speed, current detection means that detects a current of the electric fan motor, and estimation of the electric fan motor based on the vehicle speed of the vehicle speed sensor. An estimated current value grasping means for grasping the current value, grasping the estimated current value of the electric fan motor by the estimated current value grasping means based on the vehicle speed, and the current value of the electric fan motor detected by the current detecting means and the By comparing the estimated current values, it is possible to diagnose a functional failure of the electric fan motor with a simple configuration.

  The vehicle cooling fan motor failure diagnosis apparatus according to the present invention further includes a vehicle speed sensor for detecting the vehicle speed and a current detection means for detecting the current of the electric fan motor, and the current detection means when the vehicle speed detected by the vehicle speed sensor changes. By observing the change in current detected in step 1, it is possible to diagnose a fixing failure such as disconnection of the electric fan motor with a simple configuration.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a vehicle speed sensor failure diagnosis device for a vehicle according to the present invention will be described with reference to FIGS.

  FIG. 1 shows an overall configuration of an engine control system including a vehicle speed sensor failure diagnosis apparatus according to the present invention.

  The engine 201 is provided with a water temperature sensor 209 that detects the temperature of cooling water of the engine, and the cam shaft is provided with a cam angle sensor 207 that detects a cam angle. Done.

  The intake pipe 204 constituting the intake system of the engine includes an air flow sensor 205 that detects the intake air amount, a throttle throttle valve 202 that controls the intake air amount, and an ISC valve that bypasses the throttle throttle valve 202 and adjusts the intake air amount. 203, a fuel injection valve 206 for injecting fuel is provided. The intake air passes through the intake valve as an air-fuel mixture and is sucked into the combustion chamber, and a high voltage generated by the ignition module 208 generates a spark spark from the spark plug and burns it. The combusted air-fuel mixture becomes exhaust gas and is discharged from the combustion chamber when the engine exhaust valve is opened.

The engine exhaust system is provided with an O ₂ sensor 210 in front of the catalyst in the exhaust pipe. The O ₂ sensor 210 detects the oxygen concentration in the exhaust gas and outputs a binary signal. The drive shaft is provided with a vehicle speed sensor 211 that detects the vehicle speed based on the number of passing slits, and the radiator is provided with a cooling fan motor 212 that cools engine cooling water and air-conditioning refrigerant.

Signals from an air flow sensor 205, an O ₂ sensor 210, and an ignition key switch 213 which is a main switch for engine operation and stop are input to the engine control device 214. The engine control device 214 controls the fuel injection amount and the like based on the intake air amount detected by the air flow sensor 205, but may detect the intake pipe pressure of the engine and control the fuel injection amount and the like based on this. . In this embodiment, the idling speed of the engine is controlled by the ISC valve 203. However, when the opening degree of the throttle throttle valve 202 is controlled by a motor or the like, the ISC valve 203 is unnecessary.

FIG. 2 shows a control block of an engine control device provided with a vehicle speed sensor failure diagnosis device according to the present invention.
Reference numeral 101 denotes an engine speed calculation means. The engine speed calculation means 101 determines the electric signal of the crank angle sensor set at a predetermined crank angle position of the engine, mainly the number of inputs per unit time of the pulse signal change. By counting and calculating, the engine speed per unit time is calculated and output to the basic fuel calculation means 102, basic fuel correction coefficient calculation means 103, ISC control means 105, air-fuel ratio feedback control coefficient calculation means 107, etc. To do.

  The basic fuel calculation means 102 uses the engine speed calculated by the engine speed calculation means 101 and the intake air amount detected by the airflow sensor 205 as the engine load, and the basic fuel injection amount required by the engine in each operation region. Is output to the basic fuel correction means 110.

  The basic fuel correction coefficient calculation means 103 is based on the engine speed calculated by the engine speed calculation means 101 described above and the intake air amount (engine load) detected by the airflow sensor 205. A correction coefficient for the fuel injection amount is obtained from the map and output to the basic fuel correction means 110.

  The basic ignition timing calculation means 104 determines the optimum ignition timing in each operation region of the engine by map search or the like based on the engine speed and the engine load from the intake air amount described above, and outputs to the ignition timing correction means 111 To do.

  The ISC control means 105 is for keeping the engine idling speed constant, calculates the target speed at idling, sets the target flow rate through the ISC valve 203 to become the target speed, Output to the ISC flow control means 120.

  The operating state determination means 106 processes an electrical signal of the opening of the throttle throttle valve 202, determines whether the engine is in an acceleration state or a deceleration state, and outputs it to the ignition timing correction means 111. Judgment is also made.

The air-fuel ratio feedback control coefficient calculation means 107 is a mixture of fuel and air supplied to the engine 201 based on a signal from an O ₂ sensor provided in front of the catalyst, engine speed, intake air amount, and engine water temperature. However, the air-fuel ratio feedback control coefficient is calculated so as to be maintained at the final target air-fuel ratio, and is output to the basic fuel correction means 110.

  The cooling fan motor relay control means 108 includes an engine water temperature, an air conditioner SW. The driving force and the number of driving of the cooling fan motor are determined based on the state and the air conditioner refrigerant pressure.

  The vehicle speed sensor failure diagnosing means 109 detects the current of the cooling fan motor 212 during traveling according to the driving force and the driving number of the cooling fan motor 212 determined by the cooling fan motor relay control means 108, and the detected current value Based on this, the estimated vehicle speed is grasped by the estimated vehicle speed grasping means, and the vehicle speed detected by the vehicle speed sensor 211 is compared with the estimated vehicle speed to diagnose a failure of the vehicle speed sensor 211.

  The basic fuel correction means 110 is the basic fuel calculated by the basic fuel calculation means 102 based on the correction coefficient obtained by the basic fuel correction coefficient calculation means 103, the air-fuel ratio feedback control coefficient of the air-fuel ratio feedback control coefficient calculation means 107, and the like. The injection amount is corrected and output to the first to fourth cylinder fuel injection means 112 to 115. The first to fourth cylinder fuel injection means 112 to 115 supply the basic fuel injection amount calculated by the basic fuel correction means 110 to the engine.

  The ignition timing correction means 111 determines the ignition timing by correcting the basic ignition timing determined by the basic ignition timing calculation means 104 in accordance with the operating state determined by the operating state determination means 106, and determines the ignition timing. Output to cylinder ignition means 116-119. The first to fourth cylinder ignition means 116 to 119 ignite the fuel mixture flowing into the cylinder in accordance with the required ignition timing of the engine corrected by the ignition timing correction means 111 described above.

  The ISC flow rate control unit 120 drives the ISC valve so that the target flow rate during idling calculated by the ISC control unit 105 is obtained. The cooling fan relay drive unit 121 drives the cooling fan motor relay so that the cooling fan motor 212 is driven with the driving force and the number of drives determined by the cooling fan relay control unit 108 described above.

  The failure warning unit 122 notifies the driver of an abnormality of the vehicle speed sensor 211 by a lamp, sound, or the like when the vehicle speed sensor failure detection unit 109 determines that the vehicle speed sensor 211 has failed.

  In the present embodiment, the engine load is represented by the amount of air taken in, but the engine load may be represented by the pressure of the intake pipe.

  FIG. 3 shows an example of an internal configuration of an engine control device provided with a vehicle speed sensor failure diagnosis device according to the present invention.

  The engine control device 214 includes a CPU 302, an I / O 303, and a driver 304. The CPU 302 also includes a nonvolatile memory and a volatile memory, and may be connected to a backup power source for the purpose of storing the memory contents. .

  The I / O 303 converts an electrical signal input from each sensor installed in the engine into a signal for digital arithmetic processing, and the CPU 302 determines the state of the engine and determines the fuel injection amount, ignition timing, etc. required by the engine. Calculation is performed based on a predetermined procedure stored in the non-volatile memory, and the calculated value is sent to the driver 304. The driver 304 converts the control signal for digital calculation into an actual actuator drive signal and outputs it to the actuator.

  3 includes a water temperature sensor 209, a vehicle speed sensor 211, a crank angle sensor 305, a throttle opening sensor 306, an air flow sensor 205, a battery voltage 308, an air conditioner SW. 309, air-conditioner refrigerant pressure 310, cooling fan motor current 311, ignition SW. 213 is input, the engine control device 214 outputs a signal to the first to fourth cylinder fuel injection valves 314 to 317, and outputs an ignition timing signal to the first to fourth cylinder ignition coils 318 to 321. An ISC valve opening command value 322 is output to the ISC valve 203 and a signal is output to the cooling fan motor relay 323.

  FIG. 4 shows a block diagram of the vehicle speed sensor failure diagnosis apparatus of the present embodiment. When the vehicle is traveling, the cooling fan motor 212 receives traveling wind force from the cooling fan, and is rotated by rotational torque generated by the traveling wind force. Therefore, when the cooling fan motor 212 is driven by supplying driving power, the cooling fan motor 212 can be driven with a smaller driving current as the traveling speed increases, and when the cooling fan motor 212 is not driven. The cooling fan receives the traveling wind power and rotates to generate electric power and a current flows. This current increases as the traveling speed increases.

  The current detection means 401 detects the current output from the cooling fan motor 212 when the vehicle travels, and outputs the detected current value of the cooling fan motor 212 to the AD converter 402. The AD converter 402 is input The current value from the cooling fan motor 212 is A / D converted. The filtering unit 403 performs a filtering process on the A / D converted current value using a weighted average or the like and outputs the current value to the battery voltage correcting unit 404. The battery voltage correction unit 404 corrects the current value filtered by the filtering unit 403 in accordance with the battery voltage, and corrects the corrected current value that is a current value output from the cooling fan motor 212 at a predetermined battery voltage. Then, the corrected current value is output to the estimated vehicle speed grasping means 405.

  The estimated vehicle speed grasping means 405 includes a driving time map indicating the relationship between the corrected current value flowing through the cooling fan motor 212 and the vehicle speed when the cooling fan motor 212 is driven by the driving current, and the cooling fan motor 212 is driven. A non-driving map indicating the relationship between the current value flowing through the cooling fan motor 212 and the vehicle speed in a non-driving state in which the current is not driven is provided. The estimated vehicle speed grasping means 405 selects a map according to the driving state of the cooling fan motor 212, searches the map with the corrected current value to obtain the estimated vehicle speed, and obtains the estimated vehicle speed as the driving state learning means 406, vehicle speed sensor failure determination means. Output to 407.

  The current value output from the cooling fan motor 212 changes depending on the traveling environment. For example, when the inter-vehicle distance from the preceding vehicle is extremely short and the vehicle is running at a high vehicle speed, the traveling wind force received by the cooling fan is small. Even when traveling at the same traveling speed, the traveling wind force received by the cooling fan is not uniform depending on the traveling environment such as the inter-vehicle distance from the preceding vehicle and the wind speed and direction of the traveling place. The engine speed, the estimated vehicle speed grasped by the estimated vehicle speed grasping means 405, the engine load, the throttle opening degree, the engine water temperature, etc. are input to the driving state learning means 406. For each of the driving time and non-driving time, learning is performed based on the deviation from the previous estimated vehicle speed for each driving region depending on the engine speed, vehicle speed, engine load, etc., and the learned value is reflected in the estimated vehicle speed to obtain the estimated estimated vehicle speed. Remember as. Then, based on the estimated vehicle speed grasped by the estimated vehicle speed grasping means 405 and the learned estimated vehicle speed, the traveling environment situation is judged, and the result is outputted to the vehicle speed sensor failure judging means 407.

  The vehicle speed sensor failure determination unit 407 is not reliable because the estimated vehicle speed grasped by the estimated vehicle speed grasping unit 405 is not reliable when the traveling environment state determination result from the driving state learning unit 406 is not in the normal traveling environment state. In the case of a normal driving environment situation without determining the failure, the vehicle speed sensor is based on the vehicle speed calculated by the vehicle speed calculation means 408 based on the vehicle speed sensor 211 and the estimated vehicle speed grasped by the estimated vehicle speed grasping means 405. It is determined whether or not 211 is out of order, and if it is determined that the vehicle speed sensor 211 is out of order, a failure warning signal is output to the failure warning means 409 to notify the driver of the failure and a failure code is stored. .

  Here, the learning of the estimated vehicle speed by the driving state learning unit 406 and the failure diagnosis by the vehicle speed sensor failure determination unit 407 are performed for a certain period of time after the fluctuation amount of the engine speed is equal to or less than a certain amount and the cooling fan motor is in the rotating state. The conditions such that the throttle opening (idling ON / OFF signal substitution) is below a certain opening, the engine water temperature is above a certain value, and a certain period of time has passed after battery voltage fluctuations are satisfied. To be implemented.

  FIG. 5 shows the relationship between the current value output from the cooling fan motor 212 during vehicle travel and the vehicle speed. In a non-driving state in which no driving current is flowing to the cooling fan motor 212, the cooling fan rotates with traveling wind power when a certain vehicle speed is reached, and a current value 501 is output from the cooling fan motor 212. When the vehicle speed increases, the traveling wind force becomes stronger, so the rotation speed of the cooling fan increases, and the current value 501 output from the cooling fan motor 212 increases as the vehicle speed increases.

  In a driving state in which a driving current is supplied to the cooling fan motor 212, the driving force of the cooling fan motor 212 may be small because the cooling fan is rotated by the traveling wind power and the rotational load is reduced at a certain vehicle speed. Therefore, the current value 502 output from the cooling fan motor 212 decreases as the vehicle speed increases.

  FIG. 6 shows a normalized current value output from the cooling fan motor 212 and a corrected current value 601 obtained by performing filtering and voltage correction on the normalized current value. A basic current value is calculated by performing a weighted average on the normalized current value according to the following equation (a). Then, the corrected current value 601 is calculated by the following equation (b), that is, the corrected current value 601 is calculated by multiplying the calculated current basic value by averaging the battery voltage correction coefficient for each sampling frequency.

Current basic value = Ib × G + (1−G) × ib (a)
Ib: Initial value of current basic value
ib: Current basic value detected last time
G: Gain (filtering coefficient)

  7 and 8 show a vehicle speed sensor failure determination method of the vehicle speed sensor failure determination means 407 of FIG. 4, and FIG. 7 shows a vehicle speed sensor failure determination method when no driving current is passed through the cooling fan motor 212. The estimated vehicle speed 701, which is a reference value for determining a failure of the vehicle speed sensor, is an estimated vehicle speed upper limit value 702 set in consideration of characteristics variation, wind direction, maximum wind speed, etc. in the combined state of the cooling fan motor and the cooling fan system. A vehicle speed lower limit value 703 is set. The estimated vehicle speed 701 estimated from the current value when the vehicle travels is compared with the vehicle speed sensor output calculation vehicle speed 704 based on the vehicle speed sensor 211, and the vehicle speed sensor output calculation vehicle speed 704 based on the vehicle speed sensor 211 has the estimated vehicle speed upper and lower limit values 702 and 703. It is determined that the vehicle speed sensor 211 is malfunctioning when the exceeded state has elapsed for a certain period.

  FIG. 8 shows a vehicle speed sensor failure determination method in the case where the cooling fan motor 212 is driven by supplying a driving current. The estimated vehicle speed 801 serving as a reference value for determining a failure of the vehicle speed sensor is an estimated vehicle speed upper limit value 802 set in consideration of characteristics variation, wind direction, maximum wind speed, etc. in the combined state of the cooling fan motor and the cooling fan system. A vehicle speed lower limit value 803 is set. A state where the estimated vehicle speed 801 estimated by the corrected current value during vehicle travel is compared with the vehicle speed sensor output calculation vehicle speed 804 based on the vehicle speed sensor 211, and the vehicle speed sensor output calculation vehicle speed 804 exceeds the estimated vehicle speed upper and lower limit values 802 and 803. Determines that the vehicle speed sensor 211 is malfunctioning when a certain period of time elapses.

  FIG. 9 shows an embodiment of a cooling fan motor sticking failure diagnosis device to which the vehicle speed sensor failure diagnosis method of this embodiment is applied. In the present embodiment, it is assumed that the vehicle speed sensor 211 is operating normally.

  The current detection means 401 detects the current output from the cooling fan motor 212 when the vehicle travels, and outputs the detected current value of the cooling fan motor 212 to the AD converter 402. The AD converter 402 is input The current value from the cooling fan motor 212 is A / D converted. The filtering unit 403 performs a filtering process on the A / D converted current value using a weighted average or the like and outputs the current value to the battery voltage correcting unit 404. The battery voltage correction unit 404 corrects the current value filtered by the filtering unit 403 in accordance with the battery voltage, and corrects the corrected current value that is a current value output from the cooling fan motor 212 at a predetermined battery voltage. Then, the corrected current value is output to the cooling fan motor sticking failure determination means 901.

  The cooling fan motor sticking failure judging means 901 has a fluctuation amount of the engine speed that is not more than a certain amount, and a certain period of time has elapsed after the cooling fan motor is in a rotating state. ) Is equal to or less than a certain degree of opening, the engine water temperature is equal to or greater than a certain value, and the conditions such that a certain period of time has elapsed after the battery voltage change are satisfied, the vehicle speed calculation means 408 Based on the calculated vehicle speed and the corrected current value, the cooling fan motor sticking failure determination is performed. If it is determined that the cooling fan motor 212 has failed, the failure warning means 409 outputs a failure warning to notify the driver of the failure and stores the failure code.

  FIG. 10 shows a cooling fan motor stuck failure judging method in the cooling fan motor stuck failure judging means 901 of FIG. When the actual vehicle speed calculated by the vehicle speed calculation means 408 based on the vehicle speed sensor 211 changes from a predetermined vehicle speed condition 1 (for example, 30 km / h) to a vehicle speed condition 2 (for example, 60 km / h), or vice versa If the cooling fan motor output current value change amount 1001 detected by the current detection means 401 does not exceed a predetermined lower limit change amount 1002 when the vehicle speed condition 2 changes to the vehicle speed condition 1, the cooling fan motor It is determined that 212 is a fixing failure such as disconnection.

  FIG. 11 is a block diagram showing an embodiment of a cooling fan motor functional failure diagnosis device to which the vehicle speed sensor failure diagnosis device described with reference to FIG. 4 is applied. Is attached. In the present embodiment, it is assumed that the vehicle speed sensor 211 is operating normally.

  The estimated post-correction current grasping means 1101 includes a driving time map indicating the relationship between the post-correction current value flowing through the cooling fan motor 212 and the vehicle speed when the cooling fan motor 212 is driven by the driving current, and the cooling fan motor 212. Is provided with a non-driving map indicating the relationship between the current value flowing through the cooling fan motor 212 and the vehicle speed when the motor is not driven with the driving current. The post-estimation current grasping means 1101 selects a map according to the driving state of the cooling fan motor 212, searches the map by the vehicle speed calculated based on the vehicle speed sensor 211, grasps the post-estimation current value, and grasps the post-estimation correction. The current value is output to the cooling fan motor function failure determination means 1103.

  The current value output from the cooling fan motor 212 changes depending on the traveling environment. For example, when the inter-vehicle distance from the preceding vehicle is extremely short and the vehicle is running at a high vehicle speed, the traveling wind force received by the cooling fan is small. Even when traveling at the same traveling speed, the traveling wind force received by the cooling fan is not uniform depending on the traveling environment such as the inter-vehicle distance from the preceding vehicle and the wind speed and direction of the traveling place. The operating state learning unit 1102 receives the engine speed, the corrected current value corrected by the battery voltage correcting unit 404, the engine load, the throttle opening, the engine water temperature, and the like. The operating state learning unit 1102 includes a cooling fan motor. For each of the driving time and non-driving time of 212, learning is performed on the basis of the deviation of the corrected current value from the previous time for each operation region depending on the engine speed, the vehicle speed, the engine load, and the like, and the learned value is converted into the corrected current value. Reflected and stored as a current value after learning correction. Then, based on the corrected current value corrected by the battery voltage correcting unit 404 and the current value after learning correction, the traveling environment situation is determined, and the result is output to the cooling fan motor function failure determining unit 1103.

  The cooling fan motor functional failure determination unit 1103 has no reliability in the corrected current value from the battery voltage correction unit 404 when the traveling environment state determination result from the driving state learning unit 1102 is not in the normal traveling environment state. When the cooling fan motor 212 is not determined to be in a normal driving environment, the estimated corrected current value obtained by the estimated corrected current grasping means 1101 and the corrected current value from the battery voltage correcting means 404 are determined. Based on the above, it is determined whether or not the cooling fan motor 212 has failed. If it is determined that the cooling fan motor 212 has failed, a failure warning signal is output to the failure warning means 409 so that the driver is in trouble. Informs and stores the fault code.

  Here, the learning of the corrected current value in the operation state learning unit 1102 and the failure diagnosis by the cooling fan motor function failure determination unit 1103 are such that the fluctuation amount of the engine speed is equal to or less than a predetermined amount, and the cooling fan motor is in a rotating state. After a certain period of time, the throttle opening (can be substituted for an idle ON or OFF signal) is below a certain opening, the engine water temperature is above a certain level, and a certain period of time has elapsed since the battery voltage fluctuated It is implemented when is satisfied.

  12 and 13 show a cooling fan motor function failure determination method of the cooling fan motor function failure determination means 1103 of FIG. 11, and FIG. 12 shows a cooling fan motor function failure determination method when no drive current is passed to the cooling fan motor 212. Is shown.

  The estimated corrected current value 1201 obtained from the vehicle speed based on the vehicle speed sensor 211 serving as a reference value for determining failure of the cooling fan motor includes characteristic variations, wind direction, maximum wind speed, and the like in the combined state of the cooling fan motor and the cooling fan system. An estimated current upper limit value 1202 and an estimated current lower limit value 1203 set in consideration of the above are set. When the current value 601 from the battery voltage correction means 404 when the vehicle travels exceeds the estimated corrected current upper limit value 1202 and the estimated corrected current lower limit value 1203 for a certain period of time, the cooling fan motor 212 malfunctions. It is determined that

  FIG. 13 shows a cooling fan motor functional failure determination method in the case where the cooling fan motor 212 is driven by passing a driving current.

  The estimated corrected current value 1301 obtained from the vehicle speed based on the vehicle speed sensor 211 serving as a reference value for determining failure of the cooling fan motor includes characteristic variations, wind direction, maximum wind speed, and the like in the combined state of the cooling fan motor and the cooling fan system. An estimated current upper limit value 1302 after estimation and a current lower limit value 1303 after estimation correction are set. The cooling fan motor 212 functions when a state where the corrected current value 601 corrected by the battery voltage correcting means 404 during traveling of the vehicle exceeds the estimated corrected current upper limit value 1302 and the estimated corrected current lower limit value 1303 passes for a certain period. Determine that there is a failure.

  FIG. 14 shows an example of a flowchart of control in the vehicle speed sensor failure diagnosis apparatus of the present embodiment. In step 1401, the output of the vehicle speed sensor 211 is read, and in step 1402, the vehicle speed is calculated from the read output of the vehicle speed sensor 211. In step 1403, the driving state of whether the cooling fan motor 212 is driven or not is read. In step 1404, the current value output from the cooling fan motor 212 is read, filtering such as weighted average and arithmetic average is performed, and the filtered current value is corrected based on the battery voltage to calculate a corrected current value. In step 1405, the estimated vehicle speed is obtained from the corrected current value of the cooling fan motor. In step 1406, operation state parameters such as the throttle opening, the engine water temperature, and the engine speed are read. In step 1407, the failure determination of the vehicle speed sensor 211 is performed by comparing the estimated vehicle speed upper and lower limit values taking into consideration various variation factors and the vehicle speed based on the vehicle speed sensor 211. In step 1408, it is determined whether or not the vehicle speed sensor 211 has failed (OK / NG). If it is determined that the vehicle speed sensor 211 has not failed (OK), the process proceeds to step 1410 to cancel the failure warning. If it is determined in step 1409 that the vehicle speed sensor 211 has failed (NG), the process proceeds to step 1411 to store the failure code and warn the driver to the driver in step 1412.

  FIG. 15 shows an example of a flowchart of control in the cooling fan motor sticking failure diagnosis apparatus of the present embodiment. In step 1501, the output from the vehicle speed sensor 211 is read, and in step 1502, the vehicle speed is calculated from the read output of the vehicle speed sensor 211. In step 1503, the driving state of whether the cooling fan motor 212 is driven or not is read. In step 1504, the current value output from the cooling fan motor 212 is read, filtering such as weighted average and arithmetic average is performed, and the filtered current value is corrected based on the battery voltage to calculate a corrected current value. In step 1505, the amount of change in the corrected current value of the cooling fan motor is calculated. In step 1506, operation state parameters such as the throttle opening, the engine water temperature, and the engine speed are read. In step 1507, the cooling fan motor sticking failure is determined from the change in the vehicle speed based on the vehicle speed sensor 211 and the amount of change in the corrected current value of the cooling fan motor. In step 1508, it is determined whether or not the cooling fan motor 212 has a fixing failure (OK / NG). If it is determined that the cooling fan motor 212 has not failed (OK), the process proceeds to step 1510 to cancel the failure warning. . If it is determined in step 1509 that the cooling fan motor 212 has failed (NG), the process proceeds to step 1511 where a failure code is stored and in step 1512 the driver is warned of the failure.

  FIG. 16 shows an example of a flowchart of control in the cooling fan motor functional failure diagnosis apparatus of the present embodiment. In step 1601, the output from the vehicle speed sensor 211 is read, and in step 1602, the vehicle speed is calculated from the read output of the vehicle speed sensor 211. In step 1603, the driving state of whether the cooling fan motor 212 is driven or not is read. In step 1604, the current value output from the cooling fan motor 212 is read, filtering such as weighted average and arithmetic average is performed, and the corrected current value is calculated by correcting the filtered current value based on the battery voltage. In step 11605, operation state parameters such as the throttle opening, the engine water temperature, and the engine speed are read. In step 1606, the malfunction determination of the cooling fan motor 212 is performed based on the estimated corrected current value estimated from the vehicle speed based on the vehicle speed sensor 211 and the corrected current value of the cooling fan motor 212. In step 1607, it is determined whether or not the cooling fan motor 212 is malfunctioning (OK / NG). If it is determined that the cooling fan motor 212 is not malfunctioning (OK), the process proceeds to step 1609 to cancel the malfunction warning. . If it is determined in step 1509 that the cooling fan motor 212 has failed (NG), the process proceeds to step 1610, where the failure code is stored, and in step 1611, the driver is warned of the failure.

The control block diagram of the engine control apparatus provided with the vehicle speed sensor failure diagnosis apparatus which concerns on this invention. 1 is an overall configuration diagram of an engine control system including a vehicle speed sensor failure diagnosis apparatus according to the present invention. The internal block diagram of the engine control apparatus provided with the vehicle speed sensor failure diagnostic apparatus of this invention. The control block diagram of the vehicle speed sensor failure diagnostic apparatus of this embodiment. The figure which shows the relationship between the electric current value output from a cooling fan motor and vehicle speed at the time of vehicle travel. The figure which shows the normalized electric current value output from the cooling fan motor in this embodiment, and the electric current value after the correction | amendment. The figure for demonstrating the vehicle speed sensor failure determination method in the vehicle speed sensor failure diagnostic apparatus of this embodiment. The figure for demonstrating the vehicle speed sensor failure determination method in the vehicle speed sensor failure diagnostic apparatus of this embodiment. The control block diagram of the cooling fan motor fixation failure diagnostic apparatus of this invention. The figure for demonstrating the failure determination method of a cooling fan motor in the cooling fan motor fixation failure diagnostic apparatus of this invention. The control block diagram of the cooling fan motor functional failure diagnostic apparatus of this invention. The figure for demonstrating the failure determination method of a cooling fan motor in the cooling fan motor functional failure diagnostic apparatus of this invention. The figure for demonstrating the failure determination method of a cooling fan motor in the cooling fan motor functional failure diagnostic apparatus of this invention. The flowchart of the control in the vehicle speed sensor failure diagnostic apparatus of this embodiment. The flowchart of the control in the cooling fan motor fixation failure diagnostic apparatus of this embodiment. The flowchart of the control in the cooling fan motor functional failure diagnostic apparatus of this embodiment.

Explanation of symbols

108 ... Cooling fan motor relay control means 109 ... Vehicle speed sensor failure diagnosis means 201 ... Engine 205 ... Air flow sensor 207 ... Cam angle sensor 211 ... Vehicle speed sensor 212 ... Cooling fan motor 401 ... Current detection means 403 ... Filtering means 405 ... Estimated vehicle speed grasping Means 406 ... Driving state learning means 407 ... Vehicle speed sensor failure determination means 408 ... Vehicle speed calculation means 409 ... Failure warning means 601 ... Corrected current value 701 ... Estimated vehicle speed 702 ... Estimated vehicle speed upper limit value 703 ... Estimated vehicle speed lower limit value 801 ... Estimated vehicle speed 802 ... Estimated vehicle speed upper limit value 803 ... Estimated vehicle speed lower limit value 901 ... Cooling fan motor stuck failure determination means 1101 ... Cooling fan motor function failure determination means 1201 ... Estimated corrected current value 1202 ... Estimated corrected current upper limit value 1203 ... After estimated correction Current lower limit value 1301 ... Estimated corrected power The value 1302 ... estimating corrected current upper limit value 1303 ... estimating corrected current limit value

Claims (9)

A vehicle speed sensor failure diagnosis device for a vehicle having a vehicle speed sensor for detecting a vehicle speed and an electric fan motor for cooling cooling water and a refrigerant of an air conditioner,
The vehicle speed sensor failure diagnosis device is based on current detection means for detecting a current of the electric fan motor , which changes according to rotation of the electric fan motor, and a current value of the electric fan motor detected by the current detection means. wherein the estimated vehicle speed monitor which monitors the estimated vehicle speed, by comprising failure determination means for determining a failure of the vehicle speed sensor based on the vehicle speed detected by the vehicle speed sensor and the estimated vehicle speed grasped in the estimated vehicle speed detection means Vehicle speed sensor failure diagnosis device for vehicles.   2. The vehicle speed sensor failure diagnosis device for a vehicle according to claim 1, wherein the estimated vehicle speed grasping means grasps the estimated vehicle speed based on a preset correlation between a current value of the electric fan motor and the vehicle speed.   The vehicle speed sensor failure diagnosis apparatus includes learning means for learning an estimated vehicle speed in each driving region of the vehicle, and the learning means is based on the estimated vehicle speed in each learned driving region and the current value detected by the current detecting means. 3. The vehicle speed sensor failure diagnosis apparatus according to claim 2, wherein a traveling environment situation of the vehicle is grasped from the grasped estimated vehicle speed.   4. The vehicle speed sensor failure diagnosis apparatus according to claim 3, wherein the failure determination means determines whether or not a failure of the vehicle speed sensor is determined based on a traveling environment situation of the vehicle grasped by the learning means. An electric fan motor failure diagnosis device for a vehicle having a vehicle speed sensor for detecting a vehicle speed and an electric fan motor for cooling cooling water and a refrigerant of an air conditioner,
The electric fan motor failure diagnosis device is configured to detect current of the electric fan motor that changes according to rotation of the electric fan motor, and an estimated current of the electric fan motor based on a vehicle speed of the vehicle speed sensor. A fault for determining an electric fan motor failure based on an estimated current value grasping means for grasping a value, an estimated current value grasped by the estimated current value grasping means, and a current value of the electric fan motor detected by the current detecting means electric fan motor fault diagnosis apparatus for a vehicle, characterized in that it comprises a determining means.   6. The electric fan motor fault diagnosis for a vehicle according to claim 5, wherein the estimated current value grasping means grasps the estimated current value based on a preset correlation between the current value of the electric fan motor and the vehicle speed. apparatus.   The electric fan motor failure diagnosis apparatus includes learning means for learning the current value detected by the current detection means in each driving region of the vehicle, and the learning means includes the learned current value in each driving region and the current detection means. The vehicle electric fan motor failure diagnosis apparatus according to claim 6, wherein the vehicle traveling environment situation is grasped from the current value detected in step (a).   8. The vehicle electric fan motor failure diagnosis according to claim 7, wherein the failure determination unit determines whether or not to determine a failure of the electric fan motor based on a traveling environment situation of the vehicle grasped by the learning unit. apparatus. An electric fan motor failure diagnosis device for a vehicle having a vehicle speed sensor for detecting a vehicle speed and an electric fan motor for cooling cooling water and refrigerant of an air conditioner,
The electric fan motor failure diagnosis device detects current detection means that detects a current of the electric fan motor , which changes according to rotation of the electric fan motor, vehicle speed change detected by the vehicle speed sensor, and current detection means. electric fan motor fault diagnosis apparatus for a vehicle, characterized by comprising failure determination means for determining a failure of the electric fan motor based on the current change.

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