Vehicle fault diagnosis device

Abstract

To provide a vehicle fault diagnosis device capable of detecting transient faults.SOLUTION: A vehicle fault diagnosis device 1 includes an ECU-A 10. The ECU-A 10 has a communication abnormality detection unit 12. After detecting a communication abnormality between the ECU-A 10 and an ECU-B 20, the communication abnormality detection unit 12 determines that the fault in the ECU-B 20 is a transient fault if communication with the ECU-B 20 is normal and communication between the ECU-A 10 and the ECU-B 20 is normal.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a vehicle fault diagnosis device. [Background technology]

[0002] Patent Document 1 discloses a technology that, when a vehicle's ECU (Electronic Control Unit) detects a failure in a sensor or the like, determines whether the failure is a "continuous failure" in which the failure state continues once it has been established, or a "transient failure" in which the failure occurs or does not occur due to vibrations or the like while the vehicle is running. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-172706 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in the case of a transient failure in a microcontroller unit (hereinafter simply referred to as "microcomputer") inside an ECU such as that described in Patent Document 1 above, the ECU can be restored to a normal state by repairing the data or resetting it.

[0005] However, another ECU that communicates with an ECU that has returned to a normal state detects the communication with the ECU that has returned to a normal state as abnormal, even though the ECU has recovered from a transient failure, and is unable to determine that the problem is a transient failure of the microcontroller, resulting in the ECU that has returned to a normal state being replaced.

[0006] The present disclosure has been made in view of the above, and has an object to provide a vehicle fault diagnosis device that can detect transient faults. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems and achieve the objectives, the control device of the present disclosure is a vehicle fault diagnosis device that detects faults in on-board ECUs, and includes a main ECU having a normal detection unit capable of detecting communication abnormalities, and a plurality of sub-ECUs connected to the main ECU via a bus, wherein the main ECU has a communication abnormality detection unit capable of detecting communication abnormalities, and after detecting a communication abnormality between the main ECU and a specific sub-ECU among the plurality of sub-ECUs, if communication with any other of the plurality of sub-ECUs is normal and communication between the main ECU and the specific sub-ECU is normal, the communication abnormality detection unit determines that the fault in the specific sub-ECU is a transient fault. [Effects of the Invention]

[0008] According to the present disclosure, an effect is achieved in that a transient failure can be detected. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a block diagram showing the functional configuration of a vehicle fault diagnosis device according to one embodiment. [Figure 2] FIG. 2 is a flowchart showing an outline of the processing executed by the vehicle fault diagnosis device according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] A vehicle fault diagnosis system according to an embodiment of the present disclosure will be described below with reference to the drawings. Note that the components in the following embodiments include those that are easily replaceable by those skilled in the art, or those that are substantially identical. Furthermore, the drawings referred to in the following description merely show a schematic representation of the shape, size, and positional relationship to the extent that the contents of the present disclosure can be understood. In other words, the present disclosure is not limited to the shape, size, and positional relationship exemplified in each drawing.

[0011] [Overall configuration of vehicle fault diagnosis device] FIG. 1 is a block diagram showing the functional configuration of a vehicle fault diagnosis device according to one embodiment. The vehicle fault diagnosis device 1 shown in FIG. 1 is mounted on a vehicle such as an HEV (Hybrid Electric Vehicle), a PHEV (Plug-in Hybrid Electric Vehicle), an EV (Electric Vehicle), or an FCEV (Fuel Cell Electric Vehicle). The vehicle fault diagnosis device 1 includes an ECU-A10 functioning as a main ECU and ECU-B20 and ECU-C30 functioning as multiple sub-ECUs. The ECU-A10, ECU-B20, and ECU-C30 are connected to each other via a bus 40, which is a communication line, to enable bidirectional communication. In one embodiment, the ECU-A10 functions as the main ECU, and the ECU-B20 and ECU-C30 function as sub-ECUs.

[0012] The ECU-A10 is realized using a processor having hardware such as a CPU (Central Processing Unit), and a memory that is a temporary storage area used by the processor and stores software (programs) that can execute applications (hereinafter simply referred to as "apps"). The ECU-A10 has a power supply monitor unit 11 that monitors the vehicle power supply of the vehicle (not shown), and a communication abnormality detector 12 that detects communication abnormalities between the ECU-B20 and the ECU-C.

[0013] After detecting an abnormality in communication between ECU-A10 and ECU-B20 and ECU-C30, if communication with either ECU-B20 or ECU-C30 is normal and communication between ECU-A10 and ECU-B20 or ECU-C30 is normal, the communication abnormality detection unit 12 determines that the failure of ECU-B20 or ECU-C30 is a transient failure. Specifically, the communication abnormality detection unit 12 detects a failure such as a break in the bus 40, which is a communication line (see [1] in FIG. 1), a failure of ECU-B20 (see [2] in FIG. 1), and a failure of the power supply path to ECU-B20 (see [3] in FIG. 1). In this case, the communication anomaly detection unit 12 detects a failure such as a break in the bus 40, which is a communication line (see [1] in FIG. 1), and a failure in the power supply path to the ECU-B20 (see [3] in FIG. 1), as reproducible hardware failures, while detecting the failure in the ECU-B20 (see [2] in FIG. 1), as a transient failure. Specifically, the communication anomaly detection unit 12 distinguishes between the failure in the power supply path to the ECU-B20 (see [3] in FIG. 1) and the failure in the ECU-B20 (see [2] in FIG. 1), based on the detection result of the power supply monitor 11. Furthermore, the communication anomaly detection unit 12 distinguishes between the failure in the bus 40, which is a communication line (see [1] in FIG. 1), and the failure in the power supply path to the ECU-B20 (see [3] in FIG. 1), based on the detection result of the power supply monitor 11.

[0014] The ECU-B20 is realized by using a processor having hardware such as a CPU, and a memory that is a temporary storage area used by the processor and stores software (programs) that can execute applications, etc. The ECU-B20 has a power supply input unit 21 to which power is input from a power supply, and a microcomputer 22 that controls the ECU-A10 and the ECU-C via a bus 40.

[0015] The ECU-C30 is realized by using a processor having hardware such as a CPU, and a memory that is a temporary storage area used by the processor and stores software (programs) that can execute applications, etc. The ECU-C30 executes predetermined functions.

[0016] [Processing of vehicle fault diagnosis device] Next, a description will be given of the processing executed by the vehicle fault diagnosis device 1. Fig. 2 is a flowchart showing an outline of the processing executed by the vehicle fault diagnosis device 1.

[0017] 2, if the ECU-A10 detects a communication abnormality with the ECU-B20 (step S101: Yes), the vehicle fault diagnosis device 1 proceeds to step S102. On the other hand, if the ECU-A10 does not detect a communication abnormality with the ECU-B20 (step S101: No), the vehicle fault diagnosis device 1 ends this process.

[0018] In step S102, the communication abnormality detection unit 12 determines whether or not power is being supplied to the ECU-B20. If power is not being supplied to the ECU-B20 (step S102: Yes), the communication abnormality detection unit 12 detects an abnormality in the power supply path to the ECU-B20 (step S103). Specifically, the communication abnormality detection unit 12 detects that an abnormality has occurred in the power supply path "3" in FIG. 1 that connects the ECU-B20 to a power source (not shown). After step S103, the vehicle fault diagnosis device 1 ends this process. On the other hand, if power is being supplied to the ECU-B20 (step S102: No), the vehicle fault diagnosis device 1 proceeds to step S104.

[0019] In step S104, the communication abnormality detection unit 12 determines whether the abnormal state of the microcomputer 22 continues, and if the abnormal state of the microcomputer 22 continues (step S104: Yes), the communication abnormality detection unit 12 detects that the ECU-B20 has completely failed (step S105). Specifically, the communication abnormality detection unit 12 detects that the microcomputer 22 of the ECU-B20 has completely failed, as shown by "2" in FIG. 1. After step S105, the vehicle fault diagnosis device 1 ends this process.

[0020] In step S106, if the abnormal state of the microcomputer 22 does not continue (step S106: No), the communication abnormality detection unit 12 detects a transient failure of the ECU-B 20 (step S108) and stores the date and time in memory (step S109).

[0021] Next, the communication anomaly detection unit 12 determines whether or not ECU-B20 failures are occurring frequently based on the date and time of the transient failure of ECU-B20 stored in memory (step S110). If ECU-B20 failures are not occurring frequently (step S110: No), the ECU-B20 is determined to have recovered from the transient failure and is normal (step S111). After step S111, the vehicle fault diagnosis device 1 ends this process. On the other hand, if ECU-B20 failures are occurring frequently (step S110: Yes), the communication anomaly detection unit 12 outputs a message indicating that the ECU-B20 is likely to result in a complete failure and prompts an investigation (step S112). After step S112, the vehicle fault diagnosis device 1 ends this process.

[0022] According to the embodiment described above, after the communication abnormality detection unit 12 detects an abnormality in communication between ECU-A10 and ECU-B20 and ECU-C30, if communication with either another ECU-B20 or ECU-C30 is normal and communication between ECU-A10 and ECU-B20 or ECU-C30 is normal, the failure of ECU-B20 or ECU-C30 is determined to be a transient failure, and therefore the transient failure can be identified.

[0023] Further advantages and modifications will readily occur to those skilled in the art. The invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.

[0024] Although some of the embodiments of the present application have been described in detail above with reference to the drawings, these are merely examples, and the present invention can be implemented in other forms that have undergone various modifications and improvements based on the knowledge of those skilled in the art, including the aspects described in the disclosure of the present invention. [Explanation of symbols]

[0025] 1. Vehicle fault diagnosis device 11 Power supply monitor section 12 Communication error detection unit 21 Power input section 22 Microcomputer 40 Bus

Claims

[Claim 1] A vehicle fault diagnosis device for detecting a fault in an on-board ECU, a main ECU having a normal detection unit capable of detecting a communication abnormality; a plurality of sub-ECUs connected to the main ECU via a bus; Equipped with The main ECU A communication error detection unit capable of detecting a communication error is provided, The communication abnormality detection unit After detecting an abnormality in communication between the main ECU and a specific sub-ECU among the plurality of sub-ECUs, if communication with any of the other sub-ECUs is normal and communication between the main ECU and the specific sub-ECU is normal, determine that the failure of the specific sub-ECU is a transient failure. Vehicle fault diagnosis device.

Images