JPH0776722B2 - Vehicle diagnostic device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a vehicle diagnostic device for checking the operating status of sensors, actuators, etc. by reading the input / output data of an electronic control unit mounted on a vehicle. Regarding

[Prior Art] In recent years, the engine installed in a vehicle has been designed to electronically control the air-fuel ratio and other factors to realize comfortable drivability, purify exhaust gas, save fuel, and improve engine output. Has been.

Output signals from various sensors that detect the engine state,
Alternatively, if the output signals to various actuators such as injectors are not accurate, it becomes difficult to control the engine accurately, resulting in a decrease in drivability, exhaust emission, deterioration of fuel efficiency, and a decrease in engine output.

Recent electronic control systems have a self-diagnosis function as disclosed in Japanese Patent Laid-Open No. 59-61740 and the like, and when a failure occurs in sensors, actuators, and switches, In many cases, a self-diagnosis lamp provided on the vehicle is turned on (or blinks) to notify the failure.

However, the failure location and the details of the failure cannot be easily identified only by turning on (or blinking) the self-diagnosis lamp. Therefore, at a dealer service station or the like, the electronic control device mounted on the vehicle is used. It is indispensable to equip a vehicle diagnostic device (so-called hand computer) that can convert the output trouble data into a trouble code and display it on the display to easily check the fault location and fault content. For example, it is disclosed in JP-A-58-12848.

[Problems to be Solved by the Invention] In the meantime, the applicant of the present application filed a prior application (for example, Japanese Patent Application No. 62-300881) of the same applicant in an electronic control device mounted on a display unit of a vehicle diagnostic device. Input / output data of various sensors and actuators are converted into physical quantities and displayed, while ON / OFF of switches (eg, air conditioner switch, idle switch, neutral switch) blinks on each indicator provided in the indicator section. A technique has been disclosed in which the input / output data and the operation of the switches can be simultaneously checked by displaying.

Similarly, for example, output data of the O2 sensor, or trouble data of the self-diagnosis function provided in the electronic control unit, the most necessary data for checking the engine state, such as blinking display on the display unit. By doing so, when the operator checks the input / output data of other sensors and actuators, the input / output data of these sensors and actuators may be abnormal due to the failure of the sensors and actuators themselves. It is possible to easily discriminate whether it is shown or whether it is abnormal due to other factors.

However, conventionally, most of the above various input / output data are transmitted using a data transmission line in a time division manner. For example, as shown in FIG. 8, an electronic control unit (hereinafter referred to as “vehicle mounted”) mounted on a vehicle is used. ECU ”) 2 and the vehicle diagnostic device 25 are connected using one data transmission line RX, for example, two data THV (output voltage of throttle opening sensor)
, And O2 (output voltage of the O2 sensor) are multiplexed, and the vehicle diagnostic device 25 performs arithmetic processing in synchronization with each data (THV, O2), so it takes time to process the data,
Timing of lean and rich data of the above O2 sensor,
It was difficult to accurately grasp the operating state of the O2 sensor on the display, because the timing of blinking of the display corresponding to this occurred.

Also, when the trouble data is blinked on the display, the blinking interval does not exactly match the output interval of the self-diagnosis function on the in-vehicle ECU2 side, and the trouble code is judged from the blinking operation of this indicator. Difficult to do.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a vehicle diagnostic device that can process specific input / output data at high speed and can perform a diagnostic work more accurately and quickly. .

[Means for Solving the Problems] In order to achieve the above object, the vehicle diagnostic device according to the present invention is
In a vehicle diagnostic device for connecting to an electronic control device mounted on a vehicle and checking various input / output data of the electronic control device, a control unit provided in the vehicle diagnostic device main body and the electronic control device on the vehicle side, The data transmission line for time-divisionally transmitting the various input / output data and the dedicated transmission line for transmitting the specific input / output data are connected, and the input / output data input via the dedicated transmission line are It is characterized in that it is connected to a specific display device via the drive means of the control unit.

[Operation] In the present invention, input / output data necessary for vehicle diagnosis is specified,
By transmitting the data via the dedicated transmission line, the processing of the specified input / output data becomes faster.

Embodiments of the Invention Embodiments of the present invention will be described below with reference to the drawings.

1 to 7 show an embodiment of the present invention. FIG. 1 (a) is a schematic side view of a vehicle, FIG. 1 (b) is a front view of a vehicle diagnostic device, and FIG. FIG. 3 is a functional block diagram of the electronic control device and the vehicle diagnosis device, FIG. 4 is a flowchart showing an operation procedure of the vehicle diagnosis device, and FIG. 5 is mounted on the vehicle. 6 and 7 are flowcharts showing a specific data transmission procedure of the electronic control unit for the vehicle diagnosis device, and FIGS. 6 and 7 are system block diagrams for transmitting various input / output data using a dedicated transmission line.

In FIG. 1, reference numeral 1 is a vehicle such as an automobile, and 2 is an electronic control unit (hereinafter referred to as “vehicle-mounted ECU”) mounted on the vehicle 1 for performing air-fuel ratio control and the like, as shown in FIG. Central processing unit (CPU) 3 of ECU 2, RAM 4a, and leads
RAM (non-volatile RAM) 4b, ROM 5, and input interface 6
And the output interface 7 are connected via a bus line 8.

In addition, a cooling water temperature sensor 9 is connected to the input interface 6.
Water temperature signal TW, air-fuel ratio signal O2 of O2 sensor 10, intake air amount signal Q of intake air amount sensor 11, vehicle speed signal S of vehicle speed sensor 13, throttle opening signal Tr of throttle opening sensor 15
θ, engine speed sensor 17 speed signal N, and other sensor signals, and air conditioner switch SW1 air conditioner operation signal A
Switch signals such as C, the idle operation signal ID of the idle switch SW2, and the neutral operation signal NT of the neutral switch SW3 are input.

The in-vehicle ECU 2 processes the various signals in accordance with the program stored in the ROM 5, and the RAM 4
Once stored in a, the CPU 3 performs various arithmetic processing based on the stored data, and based on the arithmetically processed data, the kick down solenoid is operated via the output interface 7 and the drive circuit 18. 12, fuel pump relay 14, canister purge solenoid 19, EG
R actuator 20, idle control actuator 21,
A control signal is output to the ignition coil 22 and the injector 23.

Further, the constant voltage circuit 16 that supplies a constant voltage to each operating unit of the vehicle-mounted ECU 2 is connected to the battery BV via the relay contact 43a of the power relay 43. Further, the exciting coil 43b of the power supply relay 43 is connectable to the battery BV via the ignition terminal IG of the ignition switch 45.

Further, the vehicle-mounted ECU 2 is provided with a dealer self-diagnosis (D check) lamp 23a. When the self-diagnosis function built into the vehicle-mounted ECU 2 detects an abnormality in the system, the D-check lamp 23a reads out trouble data corresponding to a failure portion from the ROM 5 of the vehicle-mounted ECU 2 and stores it in the read RAM 4b. The CPU3 codes the trouble data based on the stored trouble data,
The D check lamp 23a is for displaying a faulty part, and the code display means performs appropriate lighting of a plurality of lamps or blinking of one lamp.

Further, the instrument panel of the vehicle 1 is provided with a self-diagnosis (U-check) lamp 23b for the user, and when the self-diagnosis function detects a system abnormality, it lights up to warn the driver of the abnormality.

Further, the vehicle-mounted ECU 2 is provided with an external connection connector 24, and the external connection connector 24 is connected to the vehicle diagnostic device.
The 25 input / output connectors 26 of the vehicle diagnostic device body 25a are connected via an adapter harness 27.

This vehicle diagnostic device main body 25a is provided in a dealer service station, etc., and the vehicle diagnostic device main body 25a is provided with a control unit 28, a power supply circuit 29, etc., and an external indicator unit 30, a display means, etc. A liquid crystal display unit 31, a keyboard 32, and the like, which are an example, are provided.
Further, a memory cartridge 34, which is detachable from the outside, is connected to the control unit 28 via a connector 33.

The control unit 28 includes a timer 3 including a CPU 36, a RAM 37, a frequency counter, etc., which are connected to each other via a bus line 35.
8, first I / O port 39, second I / O connected to the CPU 36
Port 40 is provided.

Output data AC, ID, NT of the various switches are input to the input side of the second I / O port 40 from the output interface 7 of the vehicle-mounted ECU 2 via a dedicated harness. Further, the mode selection data of the keyboard 32 is input to the input side of the first I / O port 39, and the control data output from the vehicle-mounted ECU 2 to the actuators and the D check lamp 23a. And the output data of the various sensors described above are input.

Most of the input / output data of the actuators and sensors are transmitted to the first I / O port 39 on a time division basis using the data transmission line RX1, which is always necessary for vehicle diagnosis. Data, for example O2 in the figure
The output data of the sensor 10 or the trouble data output to the D check lamp 23a is the exclusive transmission line R.
Input to the first I / O port 39 using X2.

Further, the indicator unit 30 is connected to the output side of the second I / O port 40, and the first I / O port 39 is also connected.
The output side of is connected to the input interface 6 of the vehicle-mounted ECU 2 and the liquid crystal display unit 31.

The indicator unit 30 is composed of light emitting diodes (LED) D1 to D10 arranged in two rows. Further, the liquid crystal display unit 31 is composed of liquid crystal cells arranged in two rows of 14 in each row in the figure.
Each of the light emitting diodes D1 to D10 is for confirming the input / output state of switches, sensors, etc., by turning on (or blinking) the light emitting diode at a specific location, that is, the operating state of each of the switches SW1 to SW3. Output signal AC, ID,
The NTs are connected to the specified light emitting diodes D1 to D3 via their own harnesses. Further, the light emitting diode D10 has trouble data output from the vehicle-mounted ECU 2 to the D check lamp 23a, or the O2 sensor 1
The output data of 0 is selectively output and displayed via the dedicated transmission line RX2.

Further, the display unit 31 displays measured values such as output voltages and pulse widths of the sensors and actuators, identification symbols (abbreviations) of the sensors and actuators, and a designated mode (see FIG. 1). (See (b)).

Further, the memory cartridge 34 is provided in the vehicle diagnostic device main body 25 in response to the program of the vehicle-mounted ECU 2 which is different for each vehicle type.
In order that a itself has compatibility, it can be selectively connected via the connector 33, and internally,
A ROM 41 that stores a diagnostic program and fixed data according to the vehicle type program is stored.

Further, the timer 38 is provided with a clock pulse oscillating element 42 which outputs a synchronizing signal.

Further, the power supply circuit 29 connected to the control unit 28 is connected to the battery BV of the vehicle 1 via the power switch SW4.

Next, the functional configurations of the vehicle-mounted ECU 2 and the vehicle diagnostic device 25 will be described with reference to FIG.

The vehicle-mounted ECU 2 includes a self-diagnosis unit 51a, a calculation unit 51b, and a failure diagnosis determination unit 52.

The self-diagnosis means 51a takes in output signals of the sensors and switches, and control signals from the calculation means 51b to the actuators, and outputs data according to the data transmission request signal TX from the vehicle diagnosis device 25. , A self-diagnosis function (not shown) provided inside while transmitting to the vehicle diagnostic device 25 via the data transmission line RX1, from the output signals of the sensors, switches, or control signals to the actuators. When a system abnormality is detected, the corresponding trouble code is read from the fixed data stored in the ROM 5, the data is once stored in the read RAM 4b, and then output to the D check lamp 23a.

In the failure diagnosis discriminating means 52, the above-mentioned D from the self-diagnosing means 51a.
The trouble code output to the check lamp 23a and the output data O2 of the O2 sensor 10 are taken in, and one of the two data is selectively transmitted to the vehicle diagnostic device 25 via the dedicated transmission line RX2. If there is an output of, the data is transmitted with priority over the output data O2 of the O2 sensor 10.

Further, the vehicle diagnostic device 25 includes a keyboard interpreting means 53, a data communicating means 54, a data calculating means 55, a display driving means 56,
Also, drive means 57 is provided.

The keyboard interpreting means 53 interprets the diagnostic mode input to the keyboard 32.

In the data communication means 54, the data transmission request signal TX corresponding to the diagnostic mode interpreted by the keyboard interpretation means 53 is transmitted.
To the self-diagnosis means 51a of the vehicle-mounted ECU 2 and the transmission request signal TX output from the self-diagnosis means 51a.
In addition to receiving the data according to the above, via the data transmission line RX1, the trouble code output from the failure diagnosis determination means 52 of the vehicle-mounted ECU 2 or the output data O2 of the O2 sensor 10 is received via the dedicated transmission line RX2. To do.

In the data calculation means 55, the data corresponding to the diagnostic mode received by the data communication means 54 via the data transmission line RX1 is calculated and converted into a physical quantity (binary number data is converted into decimal number and converted into numerical value data). To do.

The display drive means 56 outputs and displays the result calculated by the data calculation means 55 to the display section 31.

In the drive means 57, the trouble data received by the data communication means 54 via the dedicated transmission line RX2, or the drive signal corresponding to the output data O2 of the O2 sensor 10 is used as the light emitting diode D10 as a specific indicator. Output to.

Next, the operation procedure of the vehicle diagnostic device 25 will be described with reference to the flowchart of FIG. The display unit 31
The normal diagnostic mode in which the data value is output and displayed on the actual vehicle is performed.

First, after mounting the memory cartridge 34 corresponding to the vehicle type on the vehicle diagnostic device body 25a and connecting the input / output connector 26 to the external connection connector 24 of the vehicle-mounted ECU 2 via the adapter harness 27, the power switch SW4 is connected. Vehicle diagnostic device 2
Turn on the power of 5. Then, in step 101, the vehicle diagnostic device
25 is initialized.

Next, the process proceeds to step 102, waiting for a key input from the keyboard 32, and the diagnostic operator (maintenance worker)
Enter the desired diagnostic mode in 32. For example, when diagnosing the output voltage of the throttle opening sensor 15, F → 1 → 1
→ Enter ENT.

Then, the process proceeds to step 103 and the CPU provided in the control unit 28
The diagnostic mode is read at 36 and temporarily stored in a predetermined address of the RAM 37.

After that, the process proceeds to step 104, and the keyboard interpreting means 53 reads the mode stored in the RAM 37 and interprets the contents.

Then, in step 105, the in-vehicle ECU is disconnected from the data communication means 54.
The data transmission request signal TX corresponding to the diagnostic mode is output to 2. Then, the data signal in the diagnostic mode corresponding to the request signal is output from the vehicle-mounted ECU 2 via the data transmission line RX1, and the data transmitted from the vehicle-mounted ECU 2 is received by the data communication unit 54 in step 106.

Then, in step 107, the data communication means 54
A data signal corresponding to the diagnostic mode received via the data transmission line RX1 is calculated by the data calculation means 55 and converted into a physical quantity, and in step 108 the data calculation means 55 is transferred to the display unit 31 via the display drive means 56. The calculation data is output, and the data calculation means is displayed on the display unit 31.
Numerical value display (for example, 1.36V), identification symbol (for example, THV; throttle opening sensor abbreviation), code (for example, F11; diagnostic mode input by keyboard operation) based on the calculation result of 55 is displayed (No. See FIG. 1 (b)).

The transmission procedure of the output data O2 of the O2 sensor 10 or the trouble data in the vehicle-mounted ECU2 is executed according to the flowchart of FIG.

Note that the program in the transmission procedure of the output data O2 of the O2 sensor 10 in the vehicle-mounted ECU 2 or the trouble data is executed every predetermined time when the vehicle-mounted ECU 2 is powered on.

First, in step 112, the output data of the O2 sensor 10 is sequentially input to the failure diagnosis determination means 52 of the vehicle-mounted ECU 2, and in step 113, the trouble data D output from the self-diagnosis means 51a to the D check lamp 23a is taken in.

Then, the process proceeds to step 114, and the failure diagnosis determination means 52
Determines whether trouble data D has been entered,
If no trouble data D is input, it is determined to be normal operation, and the process proceeds to step 115. If trouble data D is input, it is determined that the system is abnormal and step 11 is performed.
Go to 6.

Then, in the case of normal operation, in step 115, the output data O2 of the O2 sensor 10 is output from the failure diagnosis determination means 52 to the control unit 28 of the vehicle diagnosis device 25 via the dedicated transmission line RX2 (FIG. 6). reference).

If the trouble data D is input to the failure diagnosis determining means 52, the process proceeds to step 116, and the trouble data D is transmitted from the failure diagnosis determining means 52 to the control unit 28 of the vehicle diagnostic device 25 via the dedicated transmission line RX2. Is transmitted (7th
See figure).

When the output data O2 of the O2 sensor 10 or the trouble data D is input from the failure diagnosis determination means 52 of the vehicle-mounted ECU 2 to the data communication means 54 of the vehicle diagnostic device 25 via the dedicated transmission line RX2, the drive is performed. From the means 57 to the light emitting diode D10 in the indicator unit 30, the O2 sensor 10
The output signal O2 or the operation signal corresponding to the trouble data D is output.

As shown in FIG. 6, when the output data O2 of the O2 sensor 10 is transmitted to the vehicle diagnostic device 25, the light emitting diode D1
0 blinks in synchronization with the air-fuel ratio rich or lean to inform the operator of the air-fuel ratio state.

Therefore, when the worker diagnoses the output values of the sensors or actuators displayed on the display unit 31, the light emitting diode D10 in the indicator unit 30 is diagnosed.
By grasping the operating status of the O2 sensor 10 by blinking,
It is possible to instantly determine whether the data value is in a normal output state.

Further, as shown in FIG. 7, when the trouble data D is transmitted to the vehicle diagnostic device 25, the light emitting diode D10
Flashes in synchronization with the D check lamp 23a to inform the operator of the trouble code.

The operator collates the blinking code of the light emitting diode D10 with a service manual or the like to diagnose the failure location and the failure content.

As described above, according to the present invention, the trouble data D or the lean or rich output data 02 of the O2 sensor 10 can be constantly monitored by the blinking operation of the light emitting diode D10 during the diagnosis work, so that the workability is good. Further, since the trouble code is displayed prior to the output data O2 of the O2 sensor 10, it is possible to immediately deal with the trouble when it occurs.

In addition, since the data displayed on the display unit 31 and the data displayed on the light emitting diode D10 are respectively transmitted using separate and independent transmission lines RX1 and RX2, the processing capacity is fast and a timing shift may occur. Instead, the blinking display of the light emitting diode D10 makes it possible to accurately grasp the content of the data.

[Effects of the Invention] As described above, according to the present invention, in a vehicle diagnostic device that is connected to an electronic control device mounted on a vehicle and checks various input / output data of the electronic control device, The control unit provided and the electronic control unit on the vehicle side are connected via a data transmission line for time-divisionally transmitting the various input / output data and a dedicated transmission line for transmitting specific input / output data. Moreover, since the input / output data input via the dedicated transmission line is connected to the specific display device via the drive means of the control unit, the processing speed of the specific input / output data is increased, and the diagnostic work is performed. It can be performed more accurately and quickly.

Therefore, for example, if the lean and rich data of the O2 sensor is transmitted through the dedicated transmission line, the timing of this data and the blinking timing of the display are completely synchronized, and this O2
It is possible to accurately grasp the output state of the sensor. In addition, if the trouble data is transmitted via a dedicated transmission line, the blinking interval will be synchronized with the output interval of the electronic control unit on the vehicle side, and the trouble code can be easily judged from the blinking operation of this indicator. Excellent effect is achieved.

[Brief description of drawings]

1 to 7 show an embodiment of the present invention. FIG. 1 (a) is a schematic side view of a vehicle, FIG. 1 (b) is a front view of a vehicle diagnostic device, and FIG. FIG. 3 is a functional block diagram of the electronic control device and the vehicle diagnosis device, FIG. 4 is a flowchart showing an operation procedure of the vehicle diagnosis device, and FIG. 5 is mounted on the vehicle. FIG. 6 is a flow chart showing a specific data transmission procedure of the electronic control unit for the vehicle diagnosis device, FIG. 6 and FIG. 7 are system block diagrams for transmitting various input / output data using a dedicated transmission line, and FIG. It is a system block diagram which transmits various input / output data using a data transmission line. 1 ... Vehicle, 2 ... Electronic control device, 25 ... Vehicle diagnostic device, 25a ... Vehicle diagnostic device main body, 28 ... Control unit, 57 ...
Drive means, D1 to D10 …… Display unit, RX1 …… (Time division transmission) data transmission line, RX2 …… Dedicated transmission line.

Claims (1)

[Claims] 1. A vehicle diagnostic device for connecting to an electronic control device mounted on a vehicle and checking various input / output data of the electronic control device, comprising: a controller provided in a vehicle diagnostic device main body and an electronic device on the vehicle side. The control device is connected via a data transmission line for time-divisionally transmitting the various input / output data and a dedicated transmission line for transmitting specific input / output data, and is input via this dedicated transmission line. The vehicle diagnostic device, wherein the input / output data is connected to a specific display device via the drive means of the control unit.