JP2781190B2 - Vehicle failure diagnosis device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a vehicle failure diagnosis device, and more particularly, to a vehicle failure diagnosis device for reading a failure history of a control system and a sensor system.

(Prior Art) Recently, automobiles have been equipped with a large number of electrical components in a control system and a sensor system, and a failure diagnosis system has been provided for diagnosing a failure of those components. This failure diagnosis system is designed to be able to store and read the failure history of the control system and sensor system.Connect the tester to the check terminal and check the output pattern by touching the pointer to identify the failure location. It can be detected. The contents of the failure diagnosis are troubles of various actuators such as a motor and a solenoid and sensor systems such as a vehicle speed sensor and a throttle sensor. These diagnostics are:
It tends to increase significantly as control complexity increases,
A multiplex communication system is employed to reduce the wiring harness and save space. By the way, JP 62-4658 A
In the publication, an example of a multiplex communication system provided in a vehicle is described.

(Problems to be Solved by the Invention) By the way, in the 4WS vehicle, the above-described failure diagnosis system is also provided in the sensor systems necessary for operation such as the steering angle sensors provided on the front and rear wheels and the rear G sensor. Is provided. Therefore, troubles in these sensor systems can be easily detected by reading out the failure history as described above. However, when a vehicle is carried into an assembly line or service factory to assemble or adjust a sensor-related replacement part in which trouble has occurred, a function that supports the work, that is, for example, for checking data from each sensor The function of allowing the signal output to be arbitrarily read out to the failure diagnosis device outside the vehicle is not provided in the above-described conventional failure diagnosis system. Therefore, at the time of assembling or adjusting the replacement parts, the voltage must be checked by the tester one by one, and the operation becomes inefficient, and it is not easy to obtain a predetermined assembling accuracy.

The present invention has been made in view of such circumstances, and has as its object to provide a vehicle failure diagnosis device with a function of arbitrarily reading data signal outputs from each sensor.

(Means for Solving the Problems) In order to solve the above problems, a solution of the present invention according to claim 1 is to provide a vehicle-mounted control unit to which at least signals of the first and second sensors are inputted, An external failure diagnostic device configured to be able to read out the failure history stored in the control unit by connecting the external failure diagnostic device to the external failure diagnostic device. In a failure history reading state to be read by the controller, by inputting a signal from the first sensor based on a predetermined operation to the control unit, the signal of the second sensor can be read by the external failure diagnosis device. It shall be configured.

Here, in the invention of claim 2, it is assumed that at least each signal of the sensor system in claim 1 is configured to be input to the control unit via a multiplex bus line.

(Operation) According to the first and second aspects of the present invention, the failure histories of the control system and the sensor system stored in the control unit can be arbitrarily read by the external failure diagnosis device, and the failure history is read. By inputting the signal from the first sensor based on the predetermined operation to the control unit under the state, the signal of the second sensor can also be arbitrarily read out to the external failure diagnosis device.

(Effects of the Invention) As described above, according to the first and second aspects of the present invention, in the fault diagnosis apparatus for a vehicle, the fault history of the control system and the sensor system stored in the control unit can be read. Under the reading state, the first
By inputting the signal from the sensor to the control unit, the signal of the second sensor can be read by the external failure diagnosis device. And work can be performed efficiently while checking them.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

The vehicle failure diagnosis device according to the present embodiment is a vehicle speed sensitive type.
Used in 4WS vehicles, it can read the failure history of the control system and sensor system, and also can read out the data signal output of each sensor system, which is convenient for assembly work of electrical components at service factories etc. It was made.

This failure diagnosis device for a vehicle is basically configured as shown in FIG. 1, and is operated by turning on a diagnosis switch 1 provided on the inside of the vehicle, for example, as an external command. The failure history of the control system 4 and the sensor system 5 stored in the control unit 3 can be read out via the line 2 to the display 8 of the external failure diagnosis device 7 provided outside the vehicle. The data output switch 9 is used as a second command different from the external command.
Is turned on, the data signal output circuit 10 in the control unit 3 is operated, and each data signal output of the sensor system 5 can be read out on the display 8.

More specifically, the control unit 3
Is composed of a microcomputer and performs not only the steering control required for normal operation of the 4WS vehicle but also the control related to the above-described failure diagnosis according to a program stored in advance. As shown in FIG. 2, on the input side of the control unit 3, a diagnostic switch 1, a parking brake switch, and a data output switch 9 such as a handle switch which is turned on when the handle is turned to the right by 100 degrees or more, and Sensor systems 5 such as a front steering angle sensor, a rear steering angle sensor, and a rear G sensor are connected.

On the other hand, on the output side of the control unit 3, a control system 4 including an actuator group such as a solenoid for operating a control valve for controlling a hydraulic pressure for rear wheel steering, a stepping control motor corresponding to a vehicle speed required for steering control, And external failure diagnosis device 7 provided outside the vehicle
A diagnostic connector 11 or the like as a connection terminal to is connected.

The circuit provided in the control unit 3 will be described.
Input information from the sensor system 5 is received by an input processing circuit 12, and various calculations necessary for steering control and failure diagnosis control are performed by an arithmetic processing circuit 13 based on the input information. Between the input processing circuit 12 and the arithmetic processing circuit 13,
A condition determination circuit 14 is provided, and based on an input signal from the diagnostic switch 11, a command for setting a control mode of an operation mode for performing steering control or a test mode for performing a diagnostic test to the arithmetic processing circuit 13. Is made. When the operation mode is set, an operation command required for steering control is output to an output processing circuit 15 including a driving relay and a driver element based on a calculation result performed by the calculation processing circuit 13,
The actuators 1 to 3 of the control system 4 are driven.

On the other hand, input information from the control system 4 and the sensor system 5 necessary for the diagnostic test is input into the arithmetic processing circuit 13 via the communication circuit 16 provided as an input interface circuit from the multiplex bus line 2. After the arithmetic processing, it is stored in the storage circuit 17 as a failure history. And
Although not shown, when an abnormal state is detected, an alarm function for issuing an alarm to the driver or a fail-safe function for obtaining a safe steering force even when a trouble occurs in the vehicle speed sensor. The control unit 3 has a typical failure diagnosis processing function. In FIG. 2, reference numeral 25 denotes a power supply line.

The control unit 3 is connected to the external failure diagnostic device 7 outside the vehicle via the diagnostic connector 11, and the diagnostic switch 1
Is turned on, the control unit 3 is set to the test mode, and a diagnostic test is performed. That is, the failure history stored in the storage circuit 17 is stored in the diagnostic output circuit.
The signal 18 is sent out of the unit as a failure code signal, received by the input processing circuit 19 of the external failure diagnosis device 7 via the diagnostic connector 11, converted by the signal conversion circuit 20, and displayed as a unique display pattern. 8 is read.

In this test mode, the data output switch 9
By turning on, in addition to the above fault diagnosis,
The display unit 8 displays the data signal output of the sensor system 5 in real time.
A data signal output circuit 10 is provided in the control unit 3 so that the data can be read out. That is, as described above, the data signal output circuit 10 outputs each signal output from the sensor system 5 input to the arithmetic processing circuit 13 through the communication circuit 16 from the multiplex bus line 2 and outputs the signal output from the data output switch 9. It is configured to send out as a signal output for check data to the outside according to the command. For example, when the parking brake switch is turned on while the diagnostic switch 1 is turned on, the signal output of the front steering angle sensor is transmitted and displayed according to a command from the condition determination circuit 14 to the arithmetic processing circuit 13. When the handle switch is turned on when the handle is turned to the right by 100 degrees or more, the signal output of the rear G sensor is displayed.

As described above, the vehicle failure diagnosis apparatus of the present embodiment employs multiple bus lines to capture more information, read out the failure history, and also output each data signal output of the sensor system 5 as check data. It can be arbitrarily read out to the display 8 of the external failure diagnosis device 7. Therefore, in a vehicle equipped with the present apparatus, when adjusting the assembling of the sensor system at a service factory or the like, the worker can work efficiently while checking the data.

FIGS. 3 and 4 show different embodiments. As shown in FIG. 4, a test terminal 22 (diagnostic switch) provided in an engine room 21 is switched to each terminal of the diagnostic connector 11 and short-circuited. By doing so, a failure code or a data signal output can be selected and read. That is, as shown in FIG. 3, a voltage judgment circuit 23 for judging a short-circuit state of the test terminal 22 by a voltage change is provided in the control unit 3, and an operation from the condition judgment circuit 14 is performed based on the judgment signal. A read content selection command is output to the processing circuit 13. For example, if the test terminal 22 is short-circuited to ground, the fault code is output.If the test terminal 22 is short-circuited to the 5V reference voltage terminal, the data signal output of the front steering angle is output. Are selected so as to be transmitted to and read out of the unit. In FIG. 4, reference numeral 24 denotes a check terminal.

FIG. 5 shows another embodiment, in which the control unit 3
A counting circuit 31 for counting the number of times the diagnostic switch 1 is turned on and off is provided therein, and a readout selection command is output from the condition determination circuit 14 to the arithmetic processing circuit 13 based on the counted number. That is, for example, when the diagnostic switch 1 is turned on once, a fault code is output when the switch is turned on twice, and a data signal output of the front steering angle is output when the diagnostic switch 1 is turned on three times. The data signal outputs are respectively read out.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of a vehicle fault diagnosis apparatus according to the present invention, FIG. 2 and subsequent figures show an embodiment of the present invention, FIG. FIG. 4 is a diagram showing a configuration of a vehicle failure diagnostic device according to another embodiment. FIG. 4 is a diagram showing test terminals and diagnostic connectors provided in an engine room. FIG. 5 is a vehicle failure diagnostic device according to another embodiment. FIG. 1 ... Diagnostic switch, 3 ... Control unit,
4 ... Control system, 5 ... Sensor system, 7 ... External failure diagnosis device, 9 ... Data output switch, 10 ... Data signal output circuit, 22 ... Diagnosis switch (test terminal).

Claims (2)

(57) [Claims] 1. A vehicle-mounted control unit to which at least signals of first and second sensors are input, and by connecting to the control unit, a failure history stored in the control unit can be read. A failure diagnosis device for a vehicle having an external failure diagnosis device configured as described above, wherein in a failure history reading state in which the failure history is read out by the external failure diagnosis device, the failure detection from the first sensor based on a predetermined operation is performed. A failure diagnosis device for a vehicle, wherein a signal of the second sensor is read out by the external failure diagnosis device by inputting a signal to the control unit. 2. The fault diagnosis apparatus for a vehicle according to claim 1, wherein at least each signal of the sensor system is configured to be input to the control unit via a multiplex bus line.