JPH0791310A - Self-diagnosing device for on-vehicle control device - Google Patents

Abstract

PURPOSE:To control an electronic object to be controlled, mounted on a vehicle, to diagnose abnormality, and to clearly display the results of abnormality diagnosis together with the identification of the object to be controlled. CONSTITUTION:A control unit 16 set so as to correspond to an object to be controlled, mounted on a vehicle, is provided with a master side microcomputer 301 and a slave side microcomputer 302 connected to each other by a bus-line 303, inputs signals from the same sensor group to control-process the same object to be controlled in different manner, and diagnoses abnormality of the object to be controlled. Each of the microcomputers 301, 302 has an identification code, and an output circuit 304 is connected to the microcomputer 301. The results of abnormality-diagnosis by the microcomputer 302 are outputted from the microcomputer 301, following the identification code of the microcomputer 302.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention self-diagnoses and sets the abnormal state of a device mounted on a vehicle such as an automobile, and outputs a signal informing of the abnormal state in response to a diagnostic output instruction. In addition, the present invention relates to an electronic self-diagnosis device for a vehicle-mounted control device that effectively executes a treatment corresponding to the abnormal state.

[0002]

2. Description of the Related Art Electronic devices mounted on vehicles such as automobiles tend to increase both in type and number. That is, even in one vehicle, many electronic control devices such as an engine control device, an automatic transmission device, and a brake control device are mounted. Further, even in the engine control device, there is a difference between the automatic transmission vehicle and the manual transmission vehicle, and further, in a state corresponding to the destination, the vehicle type, etc., extremely fine control suitable for each of them is executed. Therefore, when some kind of abnormality occurs in the system of these control devices due to the increase in the types of control devices mounted on such vehicles,
It is necessary to properly detect and display the occurrence of this abnormality.

As means for coping with such a problem, first, the contents of the ROM for storing the control program are made common to the respective control devices so that the contents of the program read by the external terminal can be selected, and the ROM can be selected. The number of types of devices is reduced as much as possible, the configuration of various devices is simplified, and a function called self-diagnosis function (diagnosis) is set in each control device. It is considered to detect and display the system abnormality by itself.

However, even if the self-diagnosis result of the control device is displayed by such a diagnosis, this leads to diversification of the display of the abnormality diagnosis result, and the dealer or the like actually judges the abnormal portion from the display. Difficult to do. Actually, it is necessary to refer to the manual etc. in detail.

Further, when such a control system is used to construct an engine control device, for example, a plurality of detection mechanisms such as engine speed, intake air amount, oxygen concentration in exhaust gas, throttle valve opening, etc. are detected. A plurality of control conditions such as ignition timing and fuel injection amount are arithmetically output from this control device based on the detection signal from Such a plurality of calculations may be executed by a single microcomputer or the like, but it is also conceivable that the control calculation device is constituted by a plurality of microcomputers so that separate microcomputers are in charge of the respective calculation contents. There is.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and when self-diagnosing electronic control devices and sensors mounted on a vehicle such as an automobile, An object of the present invention is to provide a self-diagnosis device for a vehicle-mounted control device that enables easy and reliable confirmation of a microcomputer that is an output target when outputting a diagnosis result.

[0007]

According to the self-diagnosis apparatus of the present invention, in the on-vehicle control apparatus for controlling the vehicle and diagnosing the vehicle, abnormality diagnosis of the equipment mounted on each vehicle is performed. And outputting the abnormality diagnosis result to the first microcomputer, transmitting the abnormality diagnosis result from the second microcomputer to the first microcomputer, and setting the abnormality detection result in the first microcomputer. The second microcomputer is provided with a unique identification code, and the unique identification code of the second microcomputer is output in addition to the diagnostic result of the second microcomputer. I am trying.

Here, the first microcomputer also has a unique identification code different from that of the second microcomputer, and the output from the output means also outputs the identification code of the first microcomputer. Things are also done.

[0009]

In the self-diagnosis device of the vehicle-mounted control device configured as described above, in the first and second microcomputers, it is determined whether or not there is an abnormal state in the target device according to a predetermined routine. This is a self-diagnosis of whether or not, and an error flag is set when an abnormal state is detected. Further, in particular, in the second microcomputer, a peculiar identification code is stored and set, and the diagnosis result by the second microcomputer is transmitted via the first microcomputer, and particularly the peculiar to this microcomputer. It is output together with the identification code. Furthermore, an identification code is set corresponding to each of the microcomputers constituting this diagnostic device, this identification code is first output in the diagnostic test mode state, and the diagnostic result is output following this identification code. For example, a code representing the existence or normal state of an error code is output together with its identification code in a microcomputer unit. Therefore, in this diagnostic mode, the device in which an abnormality has occurred is reliably discriminated by the output, and measures for the abnormality occurrence are taken. Can be executed reliably.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a vehicle-mounted engine control system that performs self-diagnosis. Intake air from an air cleaner is supplied to an engine 11 through an intake pipe 12. For this intake pipe 12, an air flow sensor 13 for measuring the intake air amount and an intake air temperature sensor 14 are set, and a slot valve driven by an accelerator pedal.
15 is set. The engine 11 includes an engine control unit 16 including a microcomputer and the like.
The control unit 16 controls the intake air amount detection signal from the air flow sensor 13,
A detection signal is supplied from a throttle sensor 17 that detects the state of the opening of the throttle valve 15, and particularly detects the fully closed state of the throttle valve 15.

The engine control unit 16 further includes a detection signal from an air-fuel ratio sensor 18 for detecting the oxygen concentration contained in exhaust gas, a battery voltage signal from a battery 19, a detection signal from a cooling water temperature sensor 20, an engine 11 A rotation signal from a distributor 21 driven by, and a detection signal corresponding to an operating state of the engine 11, such as a cylinder discrimination signal, are supplied. Then, the control unit 16 calculates the fuel injection amount and the like corresponding to the operating state of the engine 11, outputs a fuel injection command to the injectors 22a to 22d set in each of the plurality of cylinders of the engine 11, and also outputs the igniter. An ignition command signal is output to 23 to control the operation of the engine 11.

Further, in this engine control unit 16, the self-diagnosis operation of various control devices mounted on this vehicle is also executed based on the detection signals from the respective sensor groups.
Therefore, for this control unit 17, a test switch that sets a diagnostic mode for outputting the self-diagnosis result.
24 is set, and a display lamp 25 for displaying the result of the diagnostic test result is connected. Reference numeral 26 is an ignition switch that connects the battery 19 to the control unit 16, and a starter switch 28 that controls the starter motor 27 so as to interlock with the ignition switch 26 is provided.

FIG. 2 is a diagram for explaining the basic configuration of the engine control unit 16, and the control unit 16 includes a CPU 31 which constitutes a microcomputer. Input data from the analog input circuit 32 and the digital input circuit 33 is supplied to the CPU 31, and the analog input data from the analog input circuit 32 is an A / D converter.
It is converted into digital data at 34 and input to the CPU 31.

Here, for the analog input circuit 32,
Detection signal Us from the air flow sensor 13, water temperature sensor 20
Detection signal Thw from the intake air temperature sensor 14
ha and the voltage + B of the battery 19 are input. For the digital input circuit 33, the distributor 21
Cylinder discriminating signal G1 and rotation speed signal Ne from the engine, lean rich signal Ox corresponding to the oxygen concentration from the air-fuel ratio sensor 18, idle signal Idl indicating that the throttle valve 15 is fully closed, starter switch 28 starting Signal ST
A, a signal T for setting the diagnostic mode from the test terminal 24, etc. are input.

The A / D converter 34 includes a multiplexer function for sequentially selecting a plurality of signals input to the analog input circuit 32 in response to a command from the CPU 31 and converting the read signals into digital data. Composed. The power circuit 35 connects the battery 19 via the ignition switch 26.
Voltage + B is supplied to the CPU 31, and the backup power supply Batt is constantly set.

The output data from the CPU 31 is output by the output circuit 36,
This control unit 16 is supplied to each of 37 and 38.
The output circuit 36 outputs the ignition command signal IGt to the igniter 23. Further, the output circuit 37 outputs a signal W representing the result of diagnosis to control the lighting of the display lamp 25, and the output signal from the output circuit 38 indicates the fuel injection amount corresponding to the operating state of the engine 11. Injector 22
Each of a to 22d is controlled so that the amount of fuel injected into each cylinder is controlled.

FIG. 3 shows a specific circuit example of the output circuit 37 for outputting the result of the diagnosis. The transistor 372 and the transistor 372 which are turned on when the input terminal 371 becomes low level are shown. A transistor 373 that is also controlled to be in the on state in the on state is provided, and by turning on the transistor 373, the output terminal 374 is set to the low level and the display lamp 26 is turned on. Then, the input signal to the input terminal 371 is at a high level and the lamp 26 is controlled to go out,
For example, a binary code supplied to the input terminal can be visually expressed.

FIG. 4 shows a flow of an interrupt routine which is started when the A / D conversion is completed in the A / D converter 34. First, in step 101, the A / D conversion channel is fetched and the step is executed. Capture the data with 102. In step 103, the upper and lower limit values of this fetched data are checked, and in step 104 the data is stored in the storage device. When the data store is completed in this way, the next channel schedule is set in step 105, the A / D conversion for the channel corresponding to the schedule is started in step 106, and the input operation of analog data to the CPU 31 is continued. To be done.

FIG. 5 shows the flow of the upper and lower limit value check processing of step 103 in the above interrupt routine. The captured A / D converted data is converted to step 12
Compare with the upper limit set for this data channel in 1 and step 12 when the input data is below the upper limit.
Go to 2. In this step 122, the input data is compared with the lower limit value that is also set, and this routine processing is ended when the input data is larger than this lower limit value. Then, if the input data is larger than the set upper limit value or smaller than the set lower limit value in steps 121 and 122, respectively,
That is, when there is an abnormality in the input data, the process proceeds to step 123, where the standard value of the preset corresponding channel is taken in place of the data taken in here,
Further, in step 124, an error flag is set.

FIG. 6 shows the cheetin activated at a timing of every 50 mS for the test mode. First, in step 151, the state of the test switch 24 is checked,
When the switch 24 is on, the diagnostic output mode is set so that the identification code stored and set in the ROM is first output. Then, in step 152, this RO
The output of the M code is monitored, and in the state where this code has been output, the process proceeds to step 154, it is determined whether an error code corresponding to this channel exists, and step 155 or 156 is performed depending on the determination result. Proceed to. And
If there is no error code, a normal code is output in step 155, and this routine ends. If there is an error code, the error code is output in step 156, the process proceeds to step 157, and this step 157
Then, it is determined whether or not there is another error.

In step 158, the error code to be output next is determined, and in step 159, the first error code is set to be output next time. The error codes are all output in ascending order. This error code output is repeatedly executed when the switch 24 is on.

FIG. 7 shows the state of the diagnostic output result from the output circuit 37 corresponding to the above processing.
When the switch 24 is controlled to be in the ON state as shown in (A), the identification code stored in the ROM is first output as shown in (B). In this case, this identification code is generated in a short cycle so that it can be easily distinguished from other error codes. Then, a plurality of error codes are sequentially generated following this identification code. The diagnostic code consisting of this error code is repeatedly generated. The indicator lamp 25 corresponds to the output code from the output circuit 37.
Blinks in the state as shown in FIG.

That is, when the test switch 24 is turned on, the self-diagnosis diagnosis result is output in the form of an error code together with the identification code for identifying the control device that is executing the self-diagnosis. Therefore, it becomes possible to read and confirm the presence of the error together with the diagnostic object by the indicator lamp 25 which is controlled to blink corresponding to the identification code and the error code, and the appropriate action for the controlled object to the error code is effectively executed. It will be done.

FIG. 8 shows a modification of the engine control unit 16 section, in which a resistance 233 is connected and set to an input terminal 202 of a microcomputer 201 which constitutes the control unit 16. This resistor 203 is connected to the ground potential (0
V) control is performed for a manual transmission vehicle, and when connected to a 5V power source, control is performed for an automatic transmission vehicle. The signal of this voltage level is additionally output to the ROM identification code appearing in the output circuit 203.

FIG. 9 shows the state of the output data from the output circuit 204 in the control unit 16 as described above, which corresponds to the operating state of the test switch 24 as shown in FIG. When the 5V power source is connected to the vehicle and the 0V power source is connected, the identification ROM code is generated in the states shown in (B) and (C), respectively. Identification is easily performed. Further, in the case of such a configuration, when a part or all of the contents of the ROM is switched by the input terminal, it can be effectively used for confirmation.

In the control unit 16 thus set for vehicle control, the control unit 16 executes control for a large number of control objects mounted on the vehicle as described above, and controls each of these control objects. Perform self-diagnosis against. In addition, a configuration is also possible in which the control content for the same control target is shared by a plurality of microcomputers. In such a case, the detection signals from the same sensor group are input to the respective microcomputers, and in accordance with the same detection input, different control commands are output by the respective microcomputers. I am trying to do it.

FIG. 10 shows the construction of the control unit 16 of one embodiment of the present invention, which assumes such a case.
The control unit 16 is configured so that the first and second two microcomputers 301 and 302 are built therein.
Here, the first microcomputer 301 on the master side
Sets the ROM code of the second microcomputer 302 on the slave side to be read via the bus line 303 so that the ROM code of the microcomputer 301 is output subsequently.

To the first and second microcomputers 301 and 302, for example, detection signals from the same sensors are input. For example, these microcomputers 301 and 302 are supplied to the same controlled object. The microcomputer 391 and 302 are set so that different control calculations are performed respectively.

For example, when the control unit 16 constitutes an engine control unit, the master side and slave side microcomputers 301 and 302 are provided with a rotation sensor for detecting the operating state of the engine, a water temperature sensor, and an exhaust gas. Detection signals from an air-fuel ratio detection sensor that detects the oxygen concentration in the gas, a throttle opening sensor, etc. are input. For example, the ignition timing is calculated in the first microcomputer 301, and the fuel injection amount is calculated in the second microcomputer 302. To perform the operation. Then, these microcomputers 301 and 302 detect anomalies corresponding to the respective processing contents, and also monitor anomalies of connected sensors.

Here, the calculation result in the second microcomputer 302 on the slap side is sent to the master side microcomputer 301 via the bus line 303,
It is output from the output circuit 304. In this case, each of the microcomputers 301 and 302 has a unique identification code (ROM code), and the corresponding identification code is output prior to the diagnosis result from its own microcomputer in self-diagnosis. Specifically, the diagnostic result of the second microcomputer 302 is transmitted to the first microcomputer 301 after the identification code unique to this microcomputer 302, and the diagnostic result is output from the output circuit 304.

FIG. 11 shows the state of the output in the case of this embodiment, (A) shows the state of the test switch 24,
(B) shows the state of the output signal. At the head of this output signal, the ROM code of the slave side appears after the ROM code of the master side, whereby the microcomputer 301 or 302 that has performed the processing operation and self-diagnosis can identify it. To be done.

In the embodiment shown in FIG. 12, the external device 50 is connected and set to the control unit 16. That is, the external device 50 is connected to the input terminal T of the test switch 24 of the control unit 16, and the test diagnostic mode is set by the output signal from the external device 50. This facilitates synchronization between the microcomputer control unit 16 and the external device 50, and simplifies the test mode output control.

The external device 50 is composed of a microcomputer, and FIG. 13 shows a flow of operating states of the microcomputer which constitutes the external device 50. This routine is started, for example, every 4 mS, and the control unit
An output signal W from 16 with noise removed by hardware and software is used.

That is, when the start switch set for the external device 50 is pressed, it is determined in step 501 that the input terminal T to the control unit 16 is in the ON state,
As a result of the judgment of the ON state, the routine proceeds to step 501, where the ROM identification code is first inputted. Then, with this ROM code being input, the error code table corresponding to this read ROM code is selected in step 503. In this case, this error code table is, for example, as shown in FIG. Then, after reading the ROM code, the error code or the normal code is read, and the code content is selected according to the selected error code table,
Lighting control of, for example, an LED set for the external device 50 is performed. If the ROM code, error code, or normal code is not entered, the LE of the communication error display is displayed.
Turn on D. For external device 50, read R
A display unit is provided for displaying the OM code for confirmation.

That is, if it is determined in step 501 that the ROM code is not input, the process proceeds to step 504, the input state of the error code is determined, and if the input of the error code is present, it is handled in step 505. Error content is displayed. If there is no error code, the process proceeds to step 506 to judge the input state of the normal code, and if there is a normal code, the normal display is executed in step 507. If the presence of the normal code is denied in step 506, a communication error is displayed in step 508.

In the above embodiment, it is conceivable that the control unit 16 outputs the diagnostic code as shown in FIG. 14 and the abnormality content target table when the test input T is turned on. . By such means, it is not necessary to have a table in the program of the external device 50, and the versatility of the external device 50 is expanded.

Other than ROM code, ROM
The content itself is partially or wholly encoded or output by a well-known serial transfer means, and this is read by an external device (microcomputer or the like), and R
Applications such as use to confirm the contents of the OM are possible. Further, although all the ROM codes and the diagnostic codes are output from the common output terminal in the embodiment, they may be output from different terminals and displayed. Further, the ROM code may be output, for example, each time the power to the control unit 16 is turned on, regardless of the test mode setting.

[0038]

As described above, in the self-diagnosis device for a vehicle-mounted control device according to the present invention, even if the self-diagnosis target is different and the microcomputer for performing the control process and the self-diagnosis is different, The identification code is displayed corresponding to each controlled object, and a very versatile self-diagnosis is executed. In particular, even if the self-diagnosis contents are diversified and complicated, the diagnosis contents are displayed in a distinguishable manner. Corresponding to each device, the treatment when the abnormal state has occurred can be performed very efficiently, and the appropriate treatment is performed.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an engine control system for explaining a vehicle-mounted control device that performs a self-diagnosis device.

FIG. 2 is a configuration diagram illustrating an engine control unit in the above system.

FIG. 3 is a diagram illustrating an example of an output circuit for outputting a diagnostic result which constitutes the unit.

FIG. 4 is a flowchart illustrating a flow of basic processing in the control unit.

FIG. 5 is a flowchart illustrating a diagnosis process in this process.

FIG. 6 is a flowchart illustrating an error code output operation.

FIG. 7 is a signal waveform diagram for explaining the state of the output diagnostic code.

FIG. 8 is a diagram illustrating another example of the control unit.

FIG. 9 is a diagram showing a state of an output signal in this control unit.

FIG. 10 is a diagram illustrating a configuration of a control unit according to an embodiment of the present invention.

FIG. 11 is a signal waveform diagram showing the state of the output signal of this embodiment.

FIG. 12 is a configuration diagram of a control unit for explaining another embodiment of the present invention.

FIG. 13 is a flowchart illustrating this embodiment.

FIG. 14 is a diagram showing a state of an error code table.

[Explanation of symbols]

11 ... Engine, 13 ... Air flow sensor, 14 ... Intake air temperature sensor, 16 ... Encidon control unit, 17 ... Throttle sensor, 18 ... Air-fuel ratio sensor, 19 ... Battery, 20 ... Cooling water temperature sensor, 24 ... Test switch, 25 ... Display Lamp, 301 ... First microcomputer (master side), 302 ... Second microcomputer (slave side), 304 ... Output circuit.

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Claims (3)

[Claims] 1. A vehicle-mounted control device, comprising: a control means for controlling a vehicle and for diagnosing the vehicle; a first microcomputer for outputting an abnormality diagnosis result of a device mounted on the vehicle; A second microcomputer that performs an abnormality diagnosis of the equipment mounted on the vehicle and outputs the abnormality diagnosis result, and a communication unit that transmits the abnormality diagnosis result from the second microcomputer to the first microcomputer. And output means for outputting the diagnosis result of the second microcomputer from the first microcomputer, the second microcomputer having a unique identification code, and the second microcomputer. In addition to the result of the diagnosis, the identification code unique to the second microcomputer is output to the output means. Self-diagnosis system board control apparatus characterized by the way. 2. The first microcomputer performs abnormality diagnosis of equipment mounted on the vehicle and has a unique identification code different from that of the second microcomputer. The self-diagnosis device for a vehicle-mounted control device according to claim 1, wherein the identification code of the first microcomputer and the abnormality diagnosis result by the first microcomputer are also output together. 3. The on-vehicle controller of claim 1 or 2, wherein the first and second microcomputers are connected to common sensors and output a diagnosis result of the sensors. Diagnostic device.