Method and apparatus for self-diagnosis for an electronic control system for vehicles

• US 5,594,646 A
• Filed: 12/19/1994
• Issued: 01/14/1997
• Est. Priority Date: 12/21/1993
• Status: Expired due to Term

• Current Assignee: Aisin AW Company Limited (Aisin Corp.)
• Original Assignee: Aisin AW Company Limited (Aisin Corp.)
• Inventors: Itoh, Yasunobu, Katoh, Kiyohide
• Primary Examiner(s): ZANELLI, MICHAEL J
• Application Number:
  US08/358,458
• Time in Patent Office: 757 Days
• Field of Search: 364/424.03, 364/424.04, 73/117.2, 73/117.3, 73/118.1
• US Class Current: 701/35
• CPC Class Codes: B60T 2270/406 Test-mode; Self-diagnosis
• CPC Class Codes: B60T 8/885 using electrical circuitry
• CPC Class Codes: B60W 2050/0045 using databus protocols
• CPC Class Codes: F02D 41/266 the computer being backed-up or assisted by another circuit, e.g. analogue
• CPC Class Codes: G06F 11/0736 in functional embedded systems, i.e. in a data processing system designed as a combination of hardware and software dedicated to performing a certain function testing or monitoring of automated control systems G05B23/02
• CPC Class Codes: G06F 11/0739 in a data processing system embedded in automotive or aircraft systems
• CPC Class Codes: G06F 11/0766 Error or fault reporting or storing
• CPC Class Codes: G06F 11/22 Detection or location of defective computer hardware by testing during standby operation or during idle time, e.g. start-up testing

Abstract

In a vehicle control system having a main electronic control unit governing a plurality of subsidiary electronic control units, each of the subsidiary units includes an automatic continuous subsidiary unit self-diagnosis procedure which generates an interrupt signal causing the main electronic control unit to retrieve date and time data from the main unit clock. This subsidiary malfunction date and time data along with details of the subsidiary unit malfunction can be stored in either the main unit memory or the respective subsidiary unit memory for subsequent retrieval and display by an operator via the main control unit. Any malfunction of the main electronic control unit is similarly detected, stored and output by the main control unit for display.

Claims

1. A self-diagnosis method for a vehicle electronic control system in which a plurality of subsidiary electronic control units are connected by a communication line to a main electronic control unit for governing the respective subsidiary electronic control units, the method comprising the steps of:

each subsidiary electronic control unit continuously diagnosing itself and signaling any detected malfunction to the main electronic control unit;

interrupting normal processing of said main electronic control unit in response to said signaling of a detected malfunction to retrieve the date and time of occurrence of the malfunction from a date and time clock; and

storing the date and time of occurrence of the detected malfunction, as well as details of the detected malfunction, in memory means of one of said main electronic control unit and the subsidiary electronic control unit detecting the malfunction.

2. A self-diagnosis apparatus for a vehicle electronic control system that includes a main electronic control unit and a plurality of subsidiary electronic control units governed by the main electronic control unit, which performs a system check function for diagnosing said main electronic control unit and a diagnosis memory function for storing the results of the execution of the system check function and results of individual self-diagnosis executed by said subsidiary electronic control units, as well as the corresponding date and time at which the malfunction occurs, said apparatus comprising:

communicating means for, when any of said subsidiary electronic control units detects a malfunction by the self-diagnosis, signaling the malfunction to said main electronic control unit;

a date and time clock;

clock processing means provided in said main electronic control unit and responsive to the malfunction signal from any of said subsidiaries electronic control units for retrieving the date and time of occurrence of the malfunction from the date and time clock; and

memory means for storing details of the malfunction of any of said subsidiary electronic control units and the date and time of occurrence of the malfunction as the result of the self-diagnosis of the respective subsidiary electronic control units, and means for, when said main electronic control unit executes the diagnosis memory function, calling and outputting the details and the date and time of a malfunction out of said memory means.

3. A self-diagnosis apparatus as set forth in claim 2, wherein said memory means is memory means of said main electronic control unit.

4. A self-diagnosis apparatus as set forth in claim 2, wherein said memory means is memory means of each of said subsidiary electronic control units.

5. A self-diagnosis apparatus as set forth in claim 2, wherein said memory means is a non-volatile memory means.

6. A self-diagnosis apparatus as set forth in claim 5, wherein said non-volatile memory is a memory device capable of electrically writing and electrically erasing information.

7. A self-diagnosis apparatus for a vehicle electronic control system comprising:

a main electronic control unit including date and time clock means, a main unit memory, and an automatic continuous main unit self-diagnosis procedure to detect a malfunction of the main electronic control unit to retrieve main unit malfunction clock data from said clock means and to store in said main unit memory the malfunction clock data along with details of the main unit malfunction;

a plurality of subsidiary electronic control units connected to and governed by said main electronic control unit;

each of said subsidiary electronic control units including a subsidiary memory and an automatic continuous subsidiary unit self-diagnosis procedure to detect a malfunction of the respective subsidiary electronic control unit to transmit a subsidiary malfunction signal to the main electronic control unit;

said main electronic control unit including an interrupt procedure responsive to the subsidiary malfunction signal for retrieving subsidiary malfunction clock data including a date and time from said clock means;

means for storing said subsidiary malfunction clock data along with details of the corresponding subsidiary malfunction in one of said main unit memory and said respective subsidiary memory; and

said main electronic control unit further including a diagnosis display procedure for retrieving and outputting the stored main unit malfunction clock data, the stored details of the main unit malfunction, the stored subsidiary malfunction clock data and the stored details of the subsidiary malfunction.

8. A self-diagnosis apparatus for a vehicle electronic control system as claimed in claim 7 wherein said storing means stores the subsidiary malfunction clock data and the details of the subsidiary malfunction in said respective subsidiary memory;

said interrupt procedure includes a function for transmitting the subsidiary malfunction clock data to the corresponding subsidiary electronic control unit; and

each of the subsidiary electronic control units include a procedure for receiving and storing the subsidiary malfunction clock data in the corresponding subsidiary memory.

9. A self-diagnosis apparatus for a vehicle electronic control system as claimed in claim 7 wherein said storing means stores the subsidiary malfunction clock data and the details of the subsidiary malfunction in said main unit memory;

each of the subsidiary electronic control units includes a procedure for transmitting the details of the subsidiary malfunction to the main electronic control unit; and

the interrupt procedure includes a function for receiving the transmitted details of the subsidiary malfunction and storing the received details of the subsidiary malfunction along with the subsidiary malfunction clock data in the main unit memory.