JP2000275145A - Vehicle diagnostic system and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify a constitution used to prevent a trouble that data is disguised due to the interference of an answer from every on-vehicle electronic control device and to reduce an increase in costs to a minimum. SOLUTION: In this vehicle diagnostic system, an engine control device 10 and an AT control device 20 are connected by a communication permission flagline 4. By the engine control device 10, the finish of the transmission of failure information is notified to the AT control device 20 via the communication permission flag line 4. The AT control device 10 transmits failure information only when it receives its notice. As a result, while many communication protocols and a complicated arbitration program are not built in the system, the respective on-vehicle electronic control devices 10, 20 can send answers sequentially with reference to a request from an OBD scan tool 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle diagnostic system for diagnosing a failure which causes control when the exhaust gas of a vehicle is degraded, and a software diagnosing system for these functions. The present invention relates to a recording medium storing a program for implementing the above.

[0002]

2. Description of the Related Art Since 1994, OBDII, which is a law on exhaust gas regulations, has been applied in the United States, in a vehicle for the United States, each on-vehicle electronic control unit (ECU) includes sensors and actuators connected to itself. It is necessary to provide a system that detects a failure that causes the exhaust gas to deteriorate and turns on a multifunction indicator lamp (MIL) to notify the driver of the failure.

[0003] Further, this failure information is based on the communication standard ISO (International Organization for Sta- tus) specified by OBDII, and particularly limited by European law since 2000.
communication with a monitor device called a general scan tool (OBD scan tool) by a communication protocol according to 9141-2,
It is displayed on the monitor.

The OBD scan tool is connected to, for example, an engine control unit and an AT (automatic transmission) control unit, which are electronic control units mounted on a vehicle, through one communication line, and outputs failure information to both control units by serial communication. Request. At this time, if there is any failure in both the engine system and the AT system, failure information is returned from both the engine control device and the AT control device via one serial communication line.

At this time, if the engine control unit and the AT control unit return a response at the same time, the data interferes on one communication line and data is garbled, and the OBD scan tool cannot receive accurate data. . In this case, arbitration (acquisition adjustment of the right to use the communication line) shifts the timing of communication between the engine control device and the AT control device, and arbitration is performed by each on-vehicle electronic control device.

In other words, according to the communication standard ISO9141-2 defined by OBDII, since a maximum of 7 bytes of data is transmitted in one response, it is necessary to transmit the failure information several times depending on the amount of data to be transmitted. . In this case, if the on-board electronic control unit that sends the failure information later does not know how many times the in-vehicle electronic control unit that has sent the failure information has sent the data, it will start transmitting at what timing. I can not decide whether to do it. In the above communication standard,
It is necessary to return a response within 25 to 50 msec from the request, and it is important to start transmission. Therefore, the arbitration program is very complicated.

Therefore, a method as shown in FIG. 10 has been conventionally proposed. That is, for example, the engine control device 1
00 and an AT control device 200,
When a failure of an electronic component is detected by the failure detection unit 201 of the AT control device 200, the failure information is encoded by a method unique to the manufacturer, and is encoded via the serial communication units 202 and 102.
The notification is once made to the engine control device 100 using a communication line different from the line for performing the communication defined by OBDII.

After that, the engine control unit 100 connects the failure information detected by its own failure detection unit 101 and the failure information sent from the AT control unit 200 by a transmission data connection unit 104. Then, the connected failure information is transmitted to the I / O according to the communication protocol defined by OBDII.
The data is output from the SO9141-2 communication unit 103 to the OBD scan tool (including the ISO9141-2 communication unit) 300. By doing so, the engine control device 1 responds to a request for output of failure information from the OBD scan tool 300.
Since only 00 responds, there is no interference of data on the communication line.

In the technique shown in FIG. 10, the failure information of the AT control device 200 is always sent to the OBD scan tool 300 via the engine control device 100 with only the configuration described above. It cannot respond to the request for only the failure information. For this reason, the AT control device 200 is provided with another serial communication unit 203, and by connecting a scan tool 400 unique to the manufacturer, only the failure information of the AT control device 200 is easily output. This type of technique is disclosed, for example, in Japanese Patent Application Laid-Open No. 7-69093.

[0010]

However, in the technique of FIG. 10, the engine control device 100
In addition to the communication protocol for communicating with the OBD scan tool 300 (ISO9141-2 communication unit 103), A
A communication protocol (serial communication unit 102) for serially communicating failure information with the T control device 200 is incorporated, and a program (transmission data) for linking the failure information of the AT control device 200 with its own failure information is transmitted. It is necessary to incorporate the coupling unit 104), which leads to increases in the number of program development steps, program memory capacity, and device manufacturing cost.

Also, in the AT control device 200, it is necessary to incorporate a communication protocol for performing serial communication with the engine control device 100, and a communication port (serial communication unit 202) for the communication is provided.
Since two communication ports, ie, a communication port (serial communication unit 203) for communicating with the scan tool 400 unique to the manufacturer, are required, there is a problem that the configuration is complicated and the manufacturing cost of the apparatus is increased.

The present invention has been made to solve such a problem, and failure information output from a plurality of on-vehicle electronic control units may cause data corruption or the like due to interference on a communication line. It is an object of the present invention to reliably prevent the occurrence of a problem, to minimize the number of communication protocols to be incorporated in each vehicle-mounted electronic control device, to simplify the configuration, and to minimize the increase in manufacturing costs.

[0013]

A vehicle diagnosis system according to the present invention is a vehicle diagnosis system for performing a failure diagnosis by obtaining vehicle information from a plurality of on-vehicle electronic control units, wherein a communication permission for permitting communication of the vehicle information is provided. Signals are transmitted and received between the plurality of on-vehicle electronic control devices. Here, the plurality of in-vehicle electronic control devices are connected by a communication permission signal line,
The communication permission signal may be transmitted and received via the communication permission signal line. Further, among the plurality of on-vehicle electronic control devices, the on-vehicle electronic control devices other than the on-vehicle electronic control device that first starts communication of the vehicle information start communication of the vehicle information after receiving the communication permission signal. May be.

In another aspect of the present invention, in response to a request for output of vehicle information from an external device, a communication permission signal for permitting the output of the vehicle information is transmitted and received between the on-vehicle electronic control units.
The on-vehicle electronic control unit sequentially outputs the vehicle information to the external device.

Here, the communication permission signal may be a flag signal which becomes a high level or a low level at the end of the communication of the vehicle information in the on-vehicle electronic control device.
Further, the communication permission signal may be a pulse signal output only when the communication of the vehicle information in the on-vehicle electronic control device ends.

According to another aspect of the present invention, there is provided a vehicle diagnosis system for performing a failure diagnosis by obtaining vehicle information from a plurality of on-vehicle electronic control devices, wherein when a certain on-vehicle electronic control device terminates the communication of the vehicle information, the other on-vehicle electronic control device performs another diagnosis. A communication completion output unit that outputs a communication permission signal to the on-vehicle electronic control device; and a determination that the communication of the vehicle information by the other on-vehicle electronic control device is permitted based on the communication permission signal output from the communication completion output unit. Means.

Also, a computer-readable recording medium according to the present invention provides a vehicle diagnosis system for obtaining a vehicle information from a plurality of on-vehicle electronic control units and performing a failure diagnosis. A program for causing a computer to function as a means for outputting a communication permission signal for permitting communication of the vehicle information to another vehicle-mounted electronic control device at times is recorded.

According to another aspect of the present invention, there is provided a vehicle diagnostic system for performing failure diagnosis by obtaining vehicle information from a plurality of on-vehicle electronic control units. A program for causing a computer to function as a judging means for judging permission of communication of the vehicle information by another vehicle-mounted electronic control device based on the permission signal is recorded.

According to the present invention configured as described above, for example, arbitration by a communication permission signal is performed between an engine control unit and an AT control unit, which are on-vehicle electronic control units, so that an external device such as an OBD scan tool can perform the arbitration. In response to the request for output of vehicle information of the first time, when the response of the engine control device ends first, the communication permission signal
This is given to the T control device, and the response from the AT control device is started accordingly. As a result, the engine control device and the AT control device can sequentially send back replies without incorporating many communication protocols and complicated arbitration programs.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram illustrating a functional configuration of a vehicle diagnostic system according to the present embodiment that complies with OBDII regulations. FIG. 2 is a diagram illustrating an overall configuration of the vehicle diagnostic system according to the present embodiment.

When performing a failure diagnosis of a vehicle in a final inspection process of vehicle production or a service site such as a dealer factory, the vehicle-mounted electronic control device mounted on the vehicle 1 as shown in FIG. An engine control device 10 and an automatic transmission (AT) control device 20 are connected to a serial communication line 3 via a connector 2 of the SAEJ1962 standard to connect an OBD as an external device.
It is connected to the scan tool 30. Then, the engine control device 10, the AT control device 20, and the OBD scan tool 30 exchange data via the communication line 3.

In this embodiment, the engine control device 10 and the AT control device 20 are connected by a communication permission flag line (communication permission signal line) 4, and the AT control device 20 Even if there is a request to output failure data, it is impossible to respond to the OBD scan tool 30 unless a communication permission signal is obtained from the engine control device 10 via the communication permission flag line 4. The communication permission signal is given when the response from the engine control device 10 to the OBD scan tool 30 is completed.

Here, specific functional configurations of the engine control device 10, the AT control device 20, and the OBD scan tool 30 will be described with reference to FIG. In FIG.
Exhaust gas related data storage unit 11 in engine control device 10
And the exhaust gas related data storage unit 2 in the AT control device 20
Reference numeral 1 denotes failure information detected by vehicle information detection means (not shown), which deteriorates the exhaust gas of sensors, actuators, switches, and other parts (not shown) connected to the engine control device 10 and the AT control device 20. It is for storing exhaust gas-related data such as the operating status and the like.

The ISO9141 in the engine control device 10
-2 communication unit 12 uses the IS in the OBD scan tool 30
Communication defined by OBDII is performed with the O9141-2 communication unit 31 via the communication line 3. That is, OB
In response to a request from the D-scan tool 30, the exhaust-gas-related data stored in the exhaust-gas-related data storage unit 11 is returned to the OBD scan tool 30 according to a code and a communication protocol defined in ISO9141-2.
The ISO9141-2 communication unit 12 also performs a process of notifying the communication completion output unit 13 when the reply to the OBD scan tool 30 is completed.

The communication completion output unit 13 is provided with an ISO 9141-
2 transmits a communication permission signal indicating that the communication from the communication unit 12 to the OBD scan tool 30 has been completed to the communication permission determination unit 2 in the AT control device 20 via the communication permission flag line 4.
Output to 3. The communication permission determination unit 23 determines whether a reply to the OBD scan tool 30 may be sent from the AT control device 20 based on the communication permission signal given from the communication completion output unit 13, and compares the determination result with ISO 914.
Inform 1-2 communication unit 22.

When a communication permission is given from the communication permission determining section 23, the ISO 9141-2 communication section 22
ISO9141-2 communication unit 3 in the D scan tool 30
The communication specified by OBDII is performed with the communication device 1 via the communication line 3. That is, in response to a request from the OBD scan tool 30, after the engine control device 10 has returned the exhaust gas-related data, the exhaust gas-related data stored in the exhaust gas-related data storage unit 21 is subjected to ISO.
The code is converted into a code defined in 9141-2 and returned to the OBD scan tool 30. OBD Scan Tool 30
Then, the failure information is displayed on the display unit 32 based on the exhaust gas related data received from the engine control device 10 and the AT control device 20.

The engine control unit 10 and the AT control unit 20 use a not-shown MIL (Malfunction Indicator Lamp) provided in the vehicle 1 based on the data stored in the exhaust gas related data storage units 11 and 21 to provide failure information. Is displayed to the driver by an alarm or the like.

Hereinafter, the operation of the vehicle diagnostic system according to the present embodiment configured as described above will be described in order. First, the OBD scan tool 30 makes an initialization request called “5 bps initialization” as shown in FIG. 3 to the engine control device 10 and the AT control device 20. This is described in the ISO9141-2 standard.

Here, first, the OBD scan tool 30
From {33 ($ is 16) representing address information of the communication partner
Is transmitted at a baud rate of 5 bps. This address information $ 33 represents a functional address (that is, it means that all the on-vehicle electronic control devices connected to the communication line 3 that may cause deterioration of the exhaust gas are requested to respond).

When the address information $ 33 is transmitted from the OBD scan tool 30, the engine control unit 10 represents the on-vehicle electronic control unit, and the baud rate is 10.4k.
$ 5 in bps (all subsequent communications are 10.4 kbps)
The information of 5, $ 08 and $ 08 is transmitted. O who received this
The BD scan tool 30 transmits information of $ F7.
Further, the engine control device 10 receiving this transmits the information of $ CC to the OBD scan tool 30, and the initialization process is completed.

After that, S described in the OBDII regulation
A command specified by the AEJ 1979 standard is requested from the OBD scan tool 30, and the on-vehicle electronic control device having data relating to the exhaust gas deterioration responds to the request. In the following, both the engine control device 10 and the AT control device 20 are the in-vehicle electronic control devices that should respond,
A case will be described as an example in which a response is made to a command called mode # 03 of the AEJ1979 standard.

As shown in FIG. 4, the communication data transmitted and received between the OBD scan tool 30 and the on-vehicle electronic control unit has a header of 3 bytes including information such as the ID and data length of the on-vehicle electronic control unit. It comprises a byte, a maximum of 7 data bytes including exhaust gas related data, and a checksum byte for error detection. For example, O
When the BD scan tool 30 requests the mode # 03, the data configuration is a data group as shown in FIG.

The mode # 03 is a command for requesting a currently occurring failure code among the codes classified according to the content of the failure. One fault code is composed of 2 bytes (described in the SAEJ2012 standard). Here, six failure codes related to the engine control device 10 and three failure codes related to the AT control device 20
When responding to the D-scan tool 30, the maximum amount of data that can be transmitted at one time is 7 bytes, so the engine control device 10 transmits the failure code in two parts. Also, one response from the AT control device 20 is required.

Therefore, a total of three responses are required. According to the ISO9141-2 standard, when there are a plurality of responses, for example, as shown in FIG.
It is stipulated that responses are made sequentially within 50 ms). Therefore, first, the engine control device 10 transmits the failure code data twice (responses # 1 and # 2), and then the AT control device 20 transmits the failure code data one time within the time P2 (response # 1). ) Choose a method.

In the vehicle diagnostic system shown in FIG. 1, the timing adjustment of which of the engine control device 10 and the AT control device 20 responds to the OBD scan tool 30 is performed between the engine control device 10 and the AT control device 20. This is performed by communication of the communication permission flag. That is, FIG.
As shown in FIG.
-2, upon receiving the failure code request command from the OBD scan tool 30, the communication unit 12 notifies the communication completion output unit 13 that the engine control device 10 is outputting the command within the time P2 immediately after the completion of the reception. AT control device 2
For the purpose of notifying to 0, the signal of the communication permission flag line 4 is set to a low voltage (low level).

Thereafter, the ISO 9 of the engine control device 10
The 141-2 communication unit 12 sends an O
When the communication of the failure code to the BD scan tool 30 is completed, the communication permission flag line 4 is set to a high voltage (high) to notify the AT control device 20 of the completion of the communication to the communication completion output unit 13. Level communication permission signal)
Order again. Communication permission determination unit 23 of AT control device 20
Monitors whether the signal of the communication permission flag line 4 is a low voltage or a high voltage, and when the signal changes from the low voltage to the high voltage,
Instructs the ISO 9141-2 communication unit 22 to start transmission of the failure code.

In the case where no failure has occurred in relation to the engine control device 10 and only the AT control device 20 is a vehicle-mounted electronic control device to which a response is made, the engine control device 1
The 0 communication completion output unit 13 maintains the signal of the communication permission flag line 4 at a high voltage even after receiving the failure code request command, for the purpose of notifying the AT control device 20 of the permission of the communication.

The communication operation of the engine control device 10 will be described with reference to the flowchart shown in FIG. In FIG. 8, first, the ISO9141-2 communication unit 12 monitors a failure code request command from the OBD scan tool 30 (step S101), and when requested, receives all request data from the OBD scan tool 30. Is stored (step S102). And
Communication completion output unit 1 that the reception of all request data has been completed
Output to 3.

The communication completion output unit 13 receiving the completion of the request data reception sets the communication permission flag line low to inform the AT control device 20 that the engine control device 10 occupies the communication line 3 shown in FIG. The voltage is set (step S103). Then, the ISO9141-2 communication unit 12
Waits for the elapse of a predetermined time P2 (25 ms) shown in FIG. 7 (step S104), and returns a response # 1 as shown in FIG.
Is transmitted to the OBD scan tool 30 (step S105).

When transmission of one response is completed, ISO 91
The 41-2 communication unit 12 determines whether transmission of all response data has been completed (step S106), and returns to step S104 if there is still remaining response data. In the example of FIG. 7, since the data of response # 2 has not been transmitted, step S10
4 and the response # 2 data is transmitted to the OBD scan tool 30 after a predetermined time P2 (25 ms) has elapsed (step S105). When the communication of all response data is completed, the communication completion output unit 13 sets the communication permission flag line to a high voltage in order to notify the AT control device 20 of the communication permission (step S107).

On the other hand, in the AT control device 20, after 25 ms or more has passed after receiving the failure code request command from the OBD scan tool 30, the communication permission determining unit 23 sets the communication permission flag line 4 to a high voltage (communication permission). )
It is determined whether or not the state is the communication state. If the state is the communication permission state, the response data is transmitted to the OBD scan tool 30. The communication operation in the above-described AT control device 20 will be described below with reference to the flowchart shown in FIG.

In FIG. 9, first, the ISO9141-2 communication unit 22 monitors whether a command for requesting a failure code has been sent from the OBD scan tool 30 (step S).
201) If requested, OBD scan tool 3
0 is received and stored (step S
202). ISO9141-completed receiving the request data
The second communication unit 22 performs the predetermined time P2 (25 m
Wait for elapse of s) (step S203). Then, the communication permission determining unit 23 determines whether the communication permission flag line is at a high voltage (communication permission) (step S204).

Here, when the communication permission determining unit 23 determines that the communication is not permitted, that is, when the communication permission flag line 4 is at the low voltage, it is determined again whether or not the communication is permitted, and the communication permission flag line Wait until 4 becomes high voltage (step S205). Then, after the determination of the communication permission, the process returns to step S203 to return to the predetermined wait time P2.
(25 ms), the response # 1 data is
Transmit to the BD scan tool 30 (Step S20)
6).

When transmission of one response is completed, ISO 91
The 41-2 communication unit 22 determines whether transmission of all response data has been completed (step S207), and returns to step S203 if there is still remaining response data. FIG.
In the example, the response data from the AT control device 20 to the OBD scan tool 30 is only the response # 1, and the transmission of all the response data has been completed.
The process returns to step S201 to wait for a request from.

As described in detail above, according to the vehicle diagnostic system of the present embodiment, the order in which the on-vehicle electronic control units 10 and 20 respond to the OBD scan tool 30 using the communication permission flag line 4 is determined. O to adjust
Under the BDII regulations, the communication timing of each of the on-vehicle electronic control units 10 and 20 can be adjusted with a simple configuration. That is, since conventional serial communication between the engine control device 10 and the AT control device 20 is not required, a communication protocol having a complicated configuration incorporated in each of the on-vehicle electronic control devices 10 and 20 can be minimized. Further, there is no need for a means for linking the exhaust gas related data of the engine control device 10 and the exhaust gas related data of the AT control device 20. As a result, the development cost of each of the on-vehicle electronic control devices 10 and 20 can be reduced, and the development program can be simplified.
It is possible to reduce the OM capacity.

Note that the vehicle diagnostic system according to the present embodiment shown in FIG.
0 CPU or MPU, ROM and R
A program that is configured by a computer system including an AM and the like and realizes the above-described functions includes a RAM and an RO.
M. In addition, it is also possible to externally supply the program to the vehicle diagnostic system of the present embodiment, and realize the functions by operating the supplied program.

In this case, means for supplying the program, for example, a recording medium storing the program,
The present invention is constituted. As a recording medium for storing the above program, for example, a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a DVD, a magnetic tape, a nonvolatile memory card, and the like can be used in addition to the RAM and the ROM. it can.

The functions of the above-described embodiments are realized not only by the computer executing the supplied program, but also by the OS (operating system) or other application software running on the computer. Such a program is also included in the embodiments of the present invention when the functions of the above-described embodiments are implemented in cooperation with the computer.

It should be noted that each of the above-described embodiments is merely an example of the embodiment for carrying out the present invention, and the technical scope of the present invention is interpreted in a limited manner. It must not be. That is, the present invention can be embodied in various forms without departing from the spirit or main features thereof.

For example, in the above-described embodiment, the AT control device 20 disables communication when the communication permission flag line 4 is at a low voltage and enables communication when the communication permission flag line 4 is at a high voltage. Communication may be permitted at some times, and communication may be disabled at a high voltage.

In the above embodiment, the low-voltage or high-voltage flag signal is always output from the communication completion output unit 13 to the communication permission determination unit 23. However, the response communication in the engine control unit 10 is completed. The pulse-like communication permission signal may be output only when the response is made (including when there is no response). In this case, the communication permission determination unit 23 monitors whether or not a pulsed communication permission signal has been input from the communication completion output unit 13, and if it has been input, responds according to ISO9141-2 so as to start response communication in the AT control device 20. An instruction is given to the communication unit 22.

In the above embodiment, a response is first started from the engine control device 10, and after the communication is completed, the AT
The controller 20 responds, but this order may be reversed. In this case, the engine control device 10 sets the communication permission determination unit 23
The AT control device 20 includes the communication completion output unit 13. Note that both the communication completion output unit 13 and the communication permission determination unit 23 may be provided in each of the engine control device 10 and the AT control device 20.

In the above embodiment, the engine control unit 10 and the AT control unit 2 are used as an example of the on-vehicle electronic control unit.
0, but other traction control (TCL) control units, ABS (Anti-lock Brak
e System) The present invention can be applied to various on-vehicle electronic control devices such as a control unit and a power steering control unit.

The arbitration is not limited to between two on-vehicle electronic control units, but can be performed between more than two units. That is, for example, it can be easily realized by connecting a plurality of in-vehicle electronic control devices in a subordinate manner by a communication permission signal line, and sequentially transmitting communication permission each time a response is completed by one in-vehicle electronic control device. In addition, the functions of the communication completion output unit 13 and the communication permission determination unit 23 are provided independently of each of the on-vehicle electronic control devices, and a completion notification of a response and a notification of communication permission are provided between the on-vehicle electronic control devices. It can also be realized by performing the operations sequentially according to a predetermined order.

The communication permission signal line may not be a dedicated line like the communication permission flag line 4 but may be an existing communication line such as the communication line 3. Further, the communication permission signal may be a signal instructing the start of communication, instead of the signal indicating the end of communication. Further, the vehicle information may be various information (regardless of whether it is normal or abnormal) of each part of the vehicle instead of the failure data, and the present invention is also applied to a system for diagnosing a failure location on an external device side based on the various information. Is done. Further, the vehicle information may include not only failure data that deteriorates exhaust gas but also failure data that is not related to exhaust gas.

[0056]

As described above, according to the present invention, each vehicle-mounted electronic control device sequentially outputs vehicle information based on a communication permission signal transmitted and received between a plurality of vehicle-mounted electronic control devices. Each of the in-vehicle electronic control units can sequentially reply to a request for obtaining vehicle information from a plurality of in-vehicle electronic control units from an external device such as an OBD scan tool without incorporating a complicated arbitration program into the system. it can. This makes it possible to reliably prevent the inconvenience of data garbled due to the in-vehicle electronic control devices simultaneously replying to each other, with a simple configuration that minimizes the increase in the cost of device manufacturing.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a functional configuration of a vehicle diagnostic system according to an embodiment that is compliant with OBDII regulations.

FIG. 2 is a diagram illustrating an overall configuration of a vehicle diagnosis system according to the present embodiment.

FIG. 3 shows “5” described in the ISO9141-2 standard.
6 is a time chart illustrating an initialization operation called “bps initialization”.

FIG. 4 is a diagram showing a byte configuration of transmission / reception data based on OBDII regulations.

FIG. 5 is a diagram showing a data configuration when a command for requesting a currently occurring failure code is transmitted.

FIG. 6 is a time chart showing a communication operation when there are a plurality of responses described in the ISO9141-2 standard.

FIG. 7 is a time chart illustrating a communication operation according to the present embodiment in which a response timing adjustment between a plurality of electronic control units is performed using a communication permission flag.

FIG. 8 is a flowchart illustrating an operation of communication in the engine control device according to the present embodiment.

FIG. 9 is a flowchart showing a communication operation in the AT control device according to the present embodiment.

FIG. 10 is a block diagram illustrating a configuration example of a conventional vehicle diagnosis system.

[Explanation of symbols]

 Reference Signs List 1 vehicle 2 connector 3 communication line 4 communication permission flag line 10 engine control device 11 exhaust gas related data storage unit 12 ISO9141-2 communication unit 13 communication completion output unit 20 AT control device 21 exhaust gas related data storage unit 22 ISO9141-2 communication unit 23 Communication permission determination unit 30 OBD scan tool 31 ISO9141-2 communication unit 32 Display unit

Claims (9)

[Claims] 1. A vehicle diagnosis system for obtaining a vehicle information from a plurality of on-vehicle electronic control devices and performing a failure diagnosis, wherein a communication permission signal for permitting communication of the vehicle information is transmitted and received between the plurality of on-vehicle electronic control devices. A vehicle diagnostic system characterized by: 2. The vehicle according to claim 1, wherein the plurality of on-vehicle electronic control units are connected by a communication permission signal line, and the communication permission signal is transmitted / received via the communication permission signal line. Diagnostic system. 3. An on-vehicle electronic control device other than the on-vehicle electronic control device that first starts communication of the vehicle information among the plurality of on-vehicle electronic control devices after receiving the communication permission signal. 3. The vehicle diagnostic system according to claim 1, wherein 4. In response to a request for output of vehicle information from an external device, a communication permission signal for permitting the output of the vehicle information is transmitted and received between the on-vehicle electronic control devices. And outputting the vehicle information to the vehicle diagnostic system. 5. The communication apparatus according to claim 1, wherein the communication permission signal is a flag signal which becomes a high level or a low level when the communication of the vehicle information in the on-vehicle electronic control device is completed. A vehicle diagnostic system according to claim 1. 6. The communication apparatus according to claim 1, wherein the communication permission signal is a pulse signal output only when communication of the vehicle information in the on-vehicle electronic control device is completed. Vehicle diagnostic system. 7. A vehicle diagnosis system for performing a failure diagnosis by obtaining vehicle information from a plurality of on-vehicle electronic control devices, wherein when a communication of the vehicle information by one on-vehicle electronic control device ends, the vehicle diagnosis system communicates with another on-vehicle electronic control device. A communication completion output unit that outputs a permission signal; and a determination unit that permits communication of the vehicle information in the other vehicle-mounted electronic control device based on the communication permission signal output from the communication completion output unit. Vehicle diagnostic system characterized by the above-mentioned. 8. A vehicle diagnosis system for performing failure diagnosis by obtaining vehicle information from a plurality of on-vehicle electronic control units, wherein when one of the on-vehicle electronic control units terminates communication of the vehicle information, the on-vehicle electronic control unit transmits the vehicle information to another on-vehicle electronic control unit. A computer-readable recording medium on which a program for causing a computer to function as a means for outputting a communication permission signal for permitting communication of the computer is recorded. 9. A vehicle diagnosis system for obtaining a vehicle information from a plurality of on-vehicle electronic control devices and performing a failure diagnosis, based on a communication permission signal output at the end of communication of the vehicle information in a certain on-vehicle electronic control device. A computer-readable recording medium having recorded thereon a program for causing a computer to function as a judging means for judging permission of communication of the vehicle information by another on-vehicle electronic control device.