JPH076877B2 - Car failure diagnostic device - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a failure diagnosis device for a vehicle, which is installed in a service station or the like and performs a failure diagnosis of a vehicle equipped with various electronic control devices.

[Prior art]

Conventionally, a dedicated checker prepared for each vehicle type is used at a dealer's service station or the like, for example, Japanese Patent Laid-Open No. 58-12848.
As shown in the publication, the vehicle information providing apparatus central control processing means is replaced with a vehicle diagnostic central control processing means which is a dedicated checker, and a series of diagnostic programs are run by a key-in of a failure diagnostic item, and the driver is run. To perform a predetermined operation, perform a diagnosis by comparing with a reference value stored in advance in the memory by the data obtained by the operating state or each data input by key operation,
The result was displayed on the display.

[Problems to be Solved by the Invention]

By the way, in the failure diagnosis device configured as described above,
When keying in a failure diagnosis item, which data in the vehicle's electronic control unit should be read depends on the experience of the user or service person, so beginners can use this failure diagnosis device to correctly and quickly diagnose a failure. It was difficult to do. The present invention has been made to solve the above problems, and an object of the present invention is to provide a failure diagnosis device for an automobile that can be easily handled even by a beginner.

[Means for solving problems]

In order to achieve the above object, the present invention relates to a failure diagnostic device for an automobile equipped with an electronic control device, wherein the electronic device is provided with a failure diagnostic device main body which performs bidirectional communication with the electronic control device via a connector. The failure code diagnosed by the failure diagnosis system of the device is read out and displayed on the display unit, and the electronic control device is requested to transmit predetermined data corresponding to the failure code. It is characterized by displaying the name or code of data.

[Action]

Based on the above configuration, when a failure code is requested by keyword input, the failure code diagnosed by the failure diagnosis system of the on-vehicle electronic control device composed of the microcomputer is read out and displayed on the display means, and displayed at a plurality of locations. If a trouble occurs, select one of them, display the data item (data name or code) to be checked, and send a request to send data corresponding to the failure code to the electronic control unit of the car. . In this way, even a beginner can accurately perform failure diagnosis without relying on the experience of the user or service person.

【Example】

An embodiment of the present invention will be described below with reference to FIGS. In FIG. 1, reference numeral 1 is an automobile, and this automobile 1
The electronic control unit 2 is mounted on the electronic control unit 2, and at the time of failure diagnosis, it is connected to the failure diagnosis unit 5 via the connector 6 via the cable 4 via the connector 3 provided on the electronic control unit 2, and bidirectional communication is performed. Is possible. In the failure diagnosis device 5, for example, a memory cartridge 7 is detachably connected, and data such as programs and reference values necessary for failure diagnosis are stored in advance in the memory cartridge 7 according to the vehicle type. The vehicle type is displayed on the label 7a, and when the vehicle type to be diagnosed changes, the memory cartridge 7 is replaced to deal with it. Further, the failure diagnosis device 5 has trouble code request means and check / trouble code selection means according to the present invention, and a keyboard for inputting keywords such as failure diagnosis items to the failure diagnosis device body 8 composed of a microcomputer. The unit 9 further includes a display means (display) 10 made of liquid crystal capable of displaying digital or analog, an indicator lamp 11 for displaying operation modes of various switches, a power switch 12, and the like. Next, referring to FIG. 2 showing the configurations of the electronic control unit 2 and the failure diagnosis unit 5, the electronic control unit 2 includes a CPU 21, an input interface 22, an output interface 23, a drive circuit 24 for outputting a control signal, and a control circuit. ROM25, which stores programs and various maps, temporarily stores data
RAM26, constant voltage circuit 27, etc., cooling water temperature sensor
31, O ₂ sensor 32, suction pipe negative pressure sensor 33, air conditioner switch 3
4, vehicle speed sensor 35, idle switch 36, throttle opening sensor 37, neutral switch 38, engine speed sensor
Each signal from 39 is taken in via the input interface 22, various control calculations such as fuel injection control, ignition timing control, idle speed control, EGR control, etc. are performed, and control signals are output via the interface 23 and drive circuit 24. Canister controller 41, EGR actuator 42, ignition coil 4
4, output to injector 45, etc. Further, the failure diagnosis device 5 includes a failure diagnosis device body 8 including a hand computer, a CPU 51, an input / output interface.
52, a RAM 53 for temporarily storing various data, a connector 54 for the memory cartridge 7 and the like, and a display 10 and a keyboard unit 9 are provided. When a failure diagnosis is to be performed, an electronic cable 4 is used via the connectors 3 and 6. Two-way communication such as exchange of various data and operation commands for failure diagnosis is performed between the input / output interface 52 and the input / output interfaces 22 and 23, which are connected to the control device 2 while being synchronized by a clock signal. , RO of memory cartridge 7
Performed according to the failure diagnosis program stored in M71, the obtained actual operating state and the corresponding reference value read from the ROM 71 are displayed on the display 10, and both data are compared to diagnose the failure. . If more advanced diagnosis is required, the host computer is connected to the input / output interface 52 via the connectors (AC) 6. Next, the operation of the check / data item selection, which is the subject of the present invention, will be described with reference to the block diagram shown in FIG. 3 and the operation flowchart shown in FIG. First, in step S100, the vehicle failure diagnosis device 5
When the power switch 12 is turned on, the CPU 51 and the like of the failure diagnosis apparatus body 8 are initialized in step S101, and in performing the next failure diagnosis, in step S102, the failure code (trouble code)
When the keyword of the transmission request is input, in step S103, the key input interpreting means 81 determines that it is a trouble code transmission request, and the trouble code requesting means 82 reads out the failure code from the vehicle-mounted electronic control unit 5, and is a display means. Display on display 10. At this time, if troubles occur at a plurality of places, one of the trouble codes to be checked (trouble code) is displayed on the display 10. Next, in step S104, the system selects the data item to be checked that corresponds to the trouble code, and displays the data item on the display 10 in step S105. Based on this display, the operator
A keyword is input from the keyboard unit 9 and sent to the electronic control unit 2 via the key input interpretation unit 81 and the communication unit 84, and the vehicle is brought to the instructed state by the main program in the failure diagnosis system for the electronic control unit in step S106. Drive,
The check data is returned via the communication means 84, and this signal is converted into a predetermined physical quantity by the physical quantity conversion means 85 and displayed on the display 10. When the trouble diagnosis in this trouble mode is completed, in step S107, if the trouble mode to be checked is, that is, if there is a request for another trouble diagnosis, the process returns to step S102 and the following operation is repeated to diagnose troubles at a plurality of points. To do. At the time when the selection of the data item to be checked in step S104 is completed, the check data item is checked in step S102 as in the dotted line shown in FIG. 3 and the flowchart shown in FIG. 5 as the second embodiment. Selection means 83
Automatically sends a request to send data to be checked from the electronic control unit 2 via the communication means 84, receives the data via the communication means 84 in step S202, and validates the signal data in step S203. The physical quantity conversion means 85 converts it into a predetermined physical quantity and displays it.
Displaying in 10 makes it possible to perform failure diagnosis more easily.

【The invention's effect】

As described above, according to the present invention, when a failure code (trouble code) is requested, the trouble code is read out from the CPU of the vehicle-mounted electronic control unit and displayed, and is displayed as a mode to be checked, Since the electronic controller is requested to transmit the data corresponding to the failure code, there is an effect that even a beginner can accurately and easily perform the failure diagnosis without requiring any particular experience. can get.

[Brief description of drawings]

1 to 4 show an embodiment of the present invention.
FIG. 1 is an external view showing a state in which an automobile failure diagnosis device is connected to an automobile electronic control device, FIG. 2 is a configuration diagram of an automobile fault diagnosis device and an automobile electronic control device, and FIG. 3 is a fault according to the present invention. FIG. 4 is a block diagram showing the configuration of the diagnostic apparatus main body, FIG. 4 is a flowchart showing its operation, and FIG. 5 is a flowchart showing the operation of the second embodiment. 2 ... Electronic control device for automobile, 5 ... Fault diagnostic device for automobile, 7 ... Memory cartridge, 8 ... Fault diagnostic device main body, 9 ... Keyboard unit, 10 ... Display means, 81 ... Key input interpretation Means, 82 ... Trouble code request means, 83 ...
… Check data item selection means, 84 …… Communication means, 85
...... Physical quantity conversion means.

Claims (1)

[Claims] 1. A failure diagnosis device for an automobile equipped with an electronic control device, comprising: a failure diagnosis device main body for bidirectional communication with the electronic control device via a connector; and a failure diagnosis system for the electronic control device. The failure code diagnosed as described above is read out and displayed on the display unit, and a request for transmitting predetermined data corresponding to the failure code is made to the electronic control unit, and the name or code of the received predetermined data is displayed. A failure diagnosis device for an automobile characterized by displaying.