JP2007265222A - Failure diagnostic method and failure diagnostic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a failure diagnostic method and a failure diagnostic device for analyzing an increased number of communication lines and electronic control devices connected to the communication lines, and discriminating abnormality of a gateway device from that of the electronic control devices connected thereto. <P>SOLUTION: The failure diagnostic device is connected with a main communication line to diagnose an open-circuit or short-circuit failure of the main communication line. When there is no failure in the main communication line, each of a plurality of electronic control devices connected with the main communication line is allowed to transmit its self-diagnostic result to the failure diagnostic device to diagnose the failure of each of the plurality of electronic control devices connected with the main communication line. When there is no failure in the plurality of electronic control devices connected with the main communication line, the self-diagnostic result of each of the plurality of electronic control devices connected with sub-communication lines is transmitted to the failure diagnostic device from the gateway device which connects the sub-communication lines, to diagnose the failure of each of the plurality of electronic control devices connected with the sub-communication lines. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a failure diagnosis method and a failure diagnosis device, and more particularly to a failure diagnosis method and a failure diagnosis device for a communication network system in which a plurality of electronic control devices having a self-diagnosis function are connected via main and sub communication lines.

  For example, in a vehicle, an ECU (Electronic Control Device) provided in each part of the vehicle performs communication via a communication network called an in-vehicle LAN (Local Area Network). As a method for performing a failure diagnosis of such a communication network system, for example, there are methods described in Patent Document 1 and Patent Document 2.

  Japanese Patent Application Laid-Open No. 2004-228561 describes that a failure portion is specified by a combination of a wiring resistance value and a communication abnormality code between electronic control devices stored in each electronic control device.

Patent Document 2 describes that the diagnostic information diagnosed by each electronic control device is aggregated by the gateway device, and the failure diagnosis of each electronic control device is performed using the control information acquired by the gateway device. Yes.
JP 2004-252963 A Japanese Patent Laid-Open No. 2002-243591

  Since the technique of Patent Document 1 employs a method of diagnosing all buses (communication lines) at the same time, when the number of buses and electronic control devices connected thereto increases, a combination table for specifying a failure site is provided. There was a problem that the analysis was difficult due to the huge amount.

  Further, in the technique of Patent Document 2, the gateway device performs failure diagnosis using only the diagnostic information received from each electronic control device, and thus cannot diagnose the abnormality of its own device. There has been a problem that it is impossible to distinguish between the abnormality of the electronic control device connected to the communication line.

  The present invention has been made in view of the above points, and can analyze even if the number of communication lines and electronic control devices connected thereto increases, and the gateway device and the electronic control connected thereto. It is an object of the present invention to provide a failure diagnosis method and a failure diagnosis device that can isolate an abnormality of a device.

The failure diagnosis method of the present invention is a failure diagnosis method for a communication network system in which a plurality of electronic control devices having a self-diagnosis function are connected via main and sub communication lines.
Connect a failure diagnosis device to the main communication line to diagnose an open or short failure of the main communication line,
When there is no failure in the main communication line, a plurality of electronic control devices connected to the main communication line are caused to transmit a self-diagnosis result to the failure diagnosis device, and are connected to the main communication line. Diagnose the failure of each electronic control unit
When there is no failure in the plurality of electronic control devices connected to the main communication line, the self-diagnosis result of each of the plurality of electronic control devices connected to the sub communication line is obtained from the gateway device connecting the sub communication line. By transmitting to the failure diagnosis device and diagnosing the failure of each of the plurality of electronic control devices connected to the sub-communication line, analysis can be performed even if the number of communication lines and electronic control devices connected thereto increases. It is possible to isolate the abnormality between the gateway device and the electronic control device connected thereto.

In the failure diagnosis method,
When a self-diagnosis result of each of the plurality of electronic control devices connected to the sub-communication line is not transmitted, a failure diagnosis device is connected to the sub-communication line to diagnose an open or short-circuit failure of the sub-communication line Can do.

The failure diagnosis device of the present invention is a failure diagnosis device for a communication network system in which a plurality of electronic control devices having a self-diagnosis function are connected by main and sub communication lines.
A first diagnostic means for connecting to the main and sub communication lines and diagnosing an open or short failure of the main and sub communication lines;
Each of the plurality of electronic control devices connected to the main communication line is caused to transmit a self-diagnosis result, the failure of each of the plurality of electronic control devices connected to the main communication line is diagnosed, and the sub communication line is connected. A second diagnosis for diagnosing a failure of each of the plurality of electronic control devices connected to the sub communication line by transmitting a self-diagnosis result of each of the plurality of electronic control devices connected to the sub communication line from the gateway device By having the means, it is possible to isolate an abnormality between the gateway device and the electronic control device connected thereto.

  According to the present invention, analysis can be performed even if the number of communication lines and electronic control devices connected to the communication line increases, and abnormalities between the gateway device and the electronic control device connected thereto can be separated.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Configuration of communication network system>
FIG. 1 shows a configuration diagram of an embodiment of a communication network system to which a failure diagnosis method of the present invention is applied. In the figure, ECUs (Electronic Control Units) 11a to 11d are connected to a main communication line 10 which is a CAN (Controlling Area Network) bus, and a connector 13 and a gateway device 14 for connecting a fault diagnosis device are provided. It is connected.

  The gateway device 14 connects the main communication line 10 and the sub communication line 20 that is a CAN bus. ECUs 21 a to 21 f are connected to the sub communication line 20, and a gateway device 24 is connected to the sub communication line 20. The gateway device 24 connects the sub communication line 20 to the sub communication line 30 that is a CAN bus. ECUs 31 a to 31 f are connected to the sub communication line 30.

  The ECUs 11a to 11d, 21a to 21f, and ECUs 31a to 31f perform various controls such as engine control, brake control, suspension control, steering control, navigation, and the like, and are provided in various parts of the vehicle. Each of the ECUs 11a to 11d, 21a to 21f, and the ECUs 31a to 31f has a self-diagnosis function, and transmits a self-diagnosis result in response to a transmission request from the failure diagnosis device or the gateway devices 14 and 24 to the request source device. To do.

  Each of the main communication line 10 and the sub communication lines 20 and 30 includes two wires CAN-H and CAN-L, and a resistance value between the two wires CAN-H and CAN-L is set to 60Ω, for example. .

<Configuration of fault diagnosis device>
FIG. 2 shows a block diagram of an embodiment of the fault diagnosis apparatus of the present invention. In the figure, the failure diagnosis apparatus is divided into a tester unit 40A and a diagnosis unit 40B. Of course, the tester unit 40A and the diagnostic unit 40B may be integrated.

  The tester unit 40A is connected to the main communication line 10 with the connection terminal 41 attached to the connector 13, or replaced with one of the ECUs connected to the sub communication lines 20 and 30. And the resistance value between the wires CAN-H and CAN-L of the main communication line 10 or the sub communication lines 20 and 30 is measured.

  The diagnosis unit 40B includes a CPU unit 42, a storage unit 43, an operation unit 44, a display unit 45, and a communication unit 46, which are connected to each other via an internal bus 47. The communication unit 46 has a connection terminal 48, and the connection terminal 48 is attached to the connector 13 and connected to the main communication line 10.

  The CPU unit 42 is connected to the main communication line 10 via the communication unit 46, and executes a diagnostic program stored in the storage unit 43 to collect self-diagnosis results of each ECU of the communication network system. Diagnose the entire network system. Operations such as diagnosis start and diagnosis item selection are input from the operation unit 44. Further, the CPU unit 42 displays the diagnosis result on the display unit 43. The storage unit 43 stores the diagnosis target and the self-diagnosis results collected from each ECU, in addition to the diagnosis program.

<Configuration of gateway device>
FIG. 3 shows a block diagram of an embodiment of the gateway devices 14 and 24. In the figure, the gateway device includes a CPU unit 52, a storage unit 53, and communication units 54 and 55, which are connected to each other via an internal bus 56. The communication units 54 and 55 have connection terminals 57 and 58, and the connection terminals 57 and 58 are connected to the main communication line 10 and the sub communication line 20 in the gateway device 14, and the sub communication line in the gateway device 24. 20 and 30.

  The CPU unit 52 controls communication between the main communication line 10 and the sub communication line 20 connected between the communication units 54 and 55 by the connection terminals 57 and 58 or between the sub communication lines 20 and 30.

  The storage unit 53 stores a communication control program and a diagnostic program, and stores self-diagnosis results collected from each ECU.

  Further, the CPU unit 52 broadcasts a self-diagnosis result transmission request to each ECU connected to the downstream communication line every predetermined time, receives a response from each ECU, and collects the self-diagnosis result. The downstream communication line is the sub communication line 20 in the gateway device 14 and the sub communication line 30 in the gateway device 24.

<Processing executed by the fault diagnosis device>
4 and 5 show a flowchart of the failure diagnosis process executed by the failure diagnosis apparatus. 4, in step S11, the connection terminal 41 of the tester unit 40A is attached to the connector 13 and connected to the main communication line 10, and the resistance value between the wires CAN-H and CAN-L is measured.

  It is determined from the resistance value measured in step S12 whether or not the main communication line 10 is open (resistance value is infinite) or short (resistance value 0Ω). If the main communication line 10 is open or shorted, the process proceeds to step S13, and the main communication line 10 is repaired.

  When the resistance value between the wires CAN-H and CAN-L of the main communication line 10 is 60Ω and there is no open or short circuit in the main communication line 10, or when the repair work of the main communication line 10 is completed, the process proceeds to step S14. .

  In step S14, the connection terminal 48 of the diagnosis unit 40B is attached to the connector 13 and connected to the main communication line 10, and a transmission request for the self-diagnosis result is sent from the diagnosis unit 40B to the ECUs 11a to 11d connected to the main communication line 10. Is broadcast, responses from the ECUs 11a to 11d are sequentially received, and self-diagnosis results are collected. In FIG. 6, a state in which a transmission request for a self-diagnosis result is transmitted by broadcasting is indicated by a solid line arrow, and a response state from each ECU is indicated by a broken line arrow.

  Next, it is determined whether or not the self-diagnosis results can be collected from all the ECUs 11a to 11d connected to the main communication line 10 in step S15, and if there is any ECU that cannot collect any self-diagnosis results, step S15 is performed. Proceeding to S16, the inspection and repair work of the unresponsive ECU and the main communication line 10 between the non-response ECU and the connector 13 are checked and repaired.

  When the self-diagnosis results can be collected from all the ECUs 11a to 11d, or when the repair work in step S16 is completed, the process proceeds to step S17. In step S17, it is determined whether or not a downstream sub-communication line is connected. If there is no downstream sub-communication line, this process is terminated.

  On the other hand, if there is a downstream sub-communication line, the processing of FIG. 5 is executed. In the configuration of FIG. 1, since the downstream sub-communication line 20 is connected to the main communication line 10 via the gateway device 14, the process proceeds from step S17 to step S21 of FIG.

  In step S21, the gateway device 14 (or 24) on the downstream side is accessed, and the self-diagnosis results of the ECUs 21a to 21f (or 31a to 31f) connected to the downstream sub communication line 20 (or 30) are read.

  In step S22, it is determined whether or not the gateway device 14 (or 24) can be accessed. If the gateway device cannot be accessed, the gateway device 14 (or 24) is regarded as a failure, and the process proceeds to step S23 to proceed to the gateway device 14. Repair (or 24).

  If the gateway device can be accessed or if the gateway device is repaired in step S23, the ECUs 21a to 21f (or 31a to 31f) connected to the downstream sub communication line 20 (or 30) in step S24. It is determined whether or not the self-diagnosis result can be read.

  If the self-diagnosis result could not be read, the ECU 21a to 21f (or 31a to 31f) connected to the downstream sub-communication line 20 (or 30) is removed in step S25, and the tester unit is located at the removed position. The connection terminal 41 of 40A is attached to the connector 13 and connected to the sub communication line 20 (or 30), and the resistance value between the wires CAN-H and CAN-L is measured.

  It is determined from the resistance value measured in step S26 whether the sub communication line 20 (or 30) is open (resistance value is infinite) or short (resistance value 0Ω). If the sub-communication line 20 (or 30) is open or shorted, the process proceeds to step S27, and the sub-communication line 20 (or 30) is repaired. If it is not open or short-circuited, the process proceeds to step S28, and the gateway device 14 (or 24) is repaired.

  If the self-diagnosis result can be read out in step S24, or if steps S27 and S28 are executed, all ECUs 21a to 21f connected to the downstream sub-communication line 20 (or 30) in step S29 (or 31a to 31f), it is determined whether or not the self-diagnosis result has been read out, and if there is any ECU that has not collected the self-diagnosis result, the process proceeds to step S30. The sub-communication line 20 (or 30) between the uncollected ECU and the gateway device 14 (or 24) is inspected and repaired.

  When the self-diagnosis results can be collected from all 21a to 21f (or 31a to 31f), or when the repair work in step S30 is completed, the process proceeds to step S31. In step S31, it is determined whether or not the downstream sub communication line 30 is connected. If there is no downstream sub communication line 30, this process is terminated. On the other hand, if there is a downstream sub-communication line 30, the process of FIG. 5 is executed again from step S21.

<Data frame of CAN protocol>
FIG. 7 shows a format of a CAN protocol data frame transmitted and received between the diagnosis unit 40B and the ECUs 11a to 11d or the gateway devices 14 and 24. In the figure, a data frame includes an SOF (Start Of Frame) field, an ID (IDentifier) field, a Control field, a Data field, a CRC (Cyclic Redundancy Check) field, an ACK (ACKnowledge) field, and an EOF (End Of Frame) field. Become.

  Here, the ID field also serves as an arbitration field. When two or more ECUs start transmission at the same time, the ID field is compared in units of 1 bit, and the ECU that has continued to output dominant (priority) for a long time is used. Acquire the transmission right. Values corresponding to request and response are defined in the Data field, and in the case of a response, a self-diagnosis result is loaded and transmitted.

  In the present invention, first, an open or short failure of the main communication line 10 is diagnosed by the tester unit 40A, and when there is no failure in the main communication line 10, the ECUs 11a to 11a connected to the main communication line 10 by the diagnosis unit 40B. Diagnose the failure of 11d.

  When there is no failure in the ECUs 11a to 11d, the diagnosis unit 40B diagnoses the failure of the ECUs 21a to 21f connected to the sub communication line 20 by the gateway device 14, and the ECU 21a to 21f is connected to the sub communication line 30 when there is no failure. The diagnosis unit 40B diagnoses a failure of the ECUs 31a to 31f.

  As described above, since diagnosis is performed in communication line units, the number of ECUs to be diagnosed at one time is small, and there are few combinations for specifying a faulty part, so that analysis is simple.

  Further, since the failure diagnosis apparatus has the tester unit 40A and the diagnosis unit 40B, the failure of the gateway devices 24 and 34 and the failure of the sub-communication lines 20 and 30 can be separated, and further connected to the sub-communication lines 20 and 30. The failure of the ECUs 21a to 21f and 31a to 31f thus made can be identified.

  Note that the tester unit 40A corresponds to the first diagnosis unit described in the claims, and the diagnosis unit 40B corresponds to the second diagnosis unit.

1 is a configuration diagram of an embodiment of a communication network system to which a failure diagnosis method of the present invention is applied. It is a block diagram of one embodiment of a failure diagnosis device of the present invention. It is a block diagram of one Embodiment of a gateway apparatus. It is a flowchart of the failure diagnosis process which a failure diagnosis apparatus performs. It is a flowchart of the failure diagnosis process which a failure diagnosis apparatus performs. It is a figure which shows the mode of the transmission request and response of a self-diagnosis result. It is a data frame format of the CAN protocol.

Explanation of symbols

10 main communication lines 11a to 11d, 21a to 21f, 31a to 31f ECU (electronic control unit)
13 Connector 14, 24 Gateway device 20, 30 Sub communication line 40A Tester unit 40B Diagnosis unit 41, 48 Connection terminal 42, 52 CPU unit 43, 53 Storage unit 44 Operation unit 45 Display unit 46, 54, 55 Communication unit

Claims (3)

In a failure diagnosis method for a communication network system in which a plurality of electronic control devices having a self-diagnosis function are connected via main and sub communication lines,
Connect a failure diagnosis device to the main communication line to diagnose an open or short failure of the main communication line,
When there is no failure in the main communication line, a plurality of electronic control devices connected to the main communication line are caused to transmit a self-diagnosis result to the failure diagnosis device, and are connected to the main communication line. Diagnose the failure of each electronic control unit
When there is no failure in the plurality of electronic control devices connected to the main communication line, the self-diagnosis result of each of the plurality of electronic control devices connected to the sub communication line is obtained from the gateway device connecting the sub communication line. A failure diagnosing method, characterized in that a failure is diagnosed in each of a plurality of electronic control devices connected to the sub communication line by being transmitted to the failure diagnosing device. The failure diagnosis method according to claim 1,
When a self-diagnosis result of each of the plurality of electronic control devices connected to the sub-communication line is not transmitted, a failure diagnosis device is connected to the sub-communication line to diagnose an open or short-circuit failure of the sub-communication line A failure diagnosis method characterized by the above. In a failure diagnosis device for a communication network system in which a plurality of electronic control devices having a self-diagnosis function are connected via main and sub communication lines,
A first diagnostic means for connecting to the main and sub communication lines and diagnosing an open or short failure of the main and sub communication lines;
Each of the plurality of electronic control devices connected to the main communication line is caused to transmit a self-diagnosis result, the failure of each of the plurality of electronic control devices connected to the main communication line is diagnosed, and the sub communication line is connected. A second diagnosis for diagnosing a failure of each of the plurality of electronic control devices connected to the sub communication line by transmitting a self-diagnosis result of each of the plurality of electronic control devices connected to the sub communication line from the gateway device A fault diagnosis apparatus comprising means.

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