On-vehicle controller failure diagnosing method and apparatus

• US 6,347,267 B1
• Filed: 08/17/1998
• Issued: 02/12/2002
• Est. Priority Date: 02/20/1996
• Status: Expired due to Fees

• Current Assignee: Komatsu Ltd., Thomson Licensing SA (Vantiva SA)
• Original Assignee: Komatsu Ltd.
• Inventors: Murakami, Takanobu
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Beaulieu, Yonel
• Application Number:
  US09/125,370
• Time in Patent Office: 1,275 Days
• Field of Search: 701/35, 701/34, 701/29, 731/16, 731/172, 731/173, 340/453, 340/455, 340/438, 340/439
• US Class Current: 701/35
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: F16H 61/12 Detecting malfunction or potential malfunction, e.g. fail safe in control of hydrostatic gearing F16H61/4192; Circumventing or fixing failures
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

Even if a power source is cut OFF while a failure is present and then the power source is turned back ON with the failure uncorrected, the details of the same failure will not be recorded as failure history data, thus permitting correct failure history data to be stored. In an on-vehicle controller failure diagnosing method in which, if a vehicle failure happens, the time at which the failure happened and the details of the failure are stored as failure history data, the details of a detected failure are stored as failure history data only if the details of the failure which existed when the power source of the on-vehicle controller was cut OFF are different from the details of the failure detected during a failure diagnosis carried out when the power source is turned back ON. Further, it is determined, during the failure diagnosis carried out after the power source of the on-vehicle controller is turned ON, whether the cause of a failure which existed when the power source was cut OFF has been eliminated, and if the cause is found to be eliminated, then it is determined that the failure which existed when the power source was cut OFF has been completely corrected, and the result is stored as failure history data.

Claims

1. An apparatus, for diagnosing a vehicle failure, comprising:

means for detecting a new failure;

means for storing a time of occurrence and details of said new failure, wherein said details include at least an indication of the new failure itself and one operating condition parameter which was present when the new failure was detected;

means for recalling details of any stored previous failure; and

means for deciding whether to store the details of the new failure, wherein the decision as to whether to store the details of said new failure is based upon a comparison of the details of the new failure and details of at least one recalled previous failure, such that no new failure details will be stored if the details of the new failure match the details of any recalled previous failure, and the details of the new failure will be stored if the details of the new failure do not match the details of any recalled previous failure.

2. An apparatus, for diagnosing a vehicle failure, as claimed in claim 1, wherein:

said means for detecting said new failure comprises a failure detection circuit;

said means for deciding whether to store the details of said new failure comprises a failure diagnosis controller; and

said means for storing the time of the occurrence and details of said new failure comprises a storage device.

3. An apparatus, for diagnosing a vehicle failure, as claimed in claim 2, said failure detection circuit comprising:

a line voltage failure detecting section;

a sensor failure detecting section;

an input section for a driving circuit output voltage; and

an input section for a clutch system failure signal.

4. An apparatus, for diagnosing a vehicle failure, as claimed in claim 2, wherein said failure diagnosis controller comprises a microcomputer.

5. An apparatus, for diagnosing a vehicle failure, as claimed in claim 2, wherein said storage device is a device selected from the group consisting of a nonvolatile random access memory, a battery backed-up complementary metal-oxide-semiconductor random access memory, an integrated circuit card memory, and a hard disk device.

6. A method, for diagnosing a vehicle failure, comprising the steps of:

detecting a new vehicle failure;

determining a time of occurrence of said new failure;

determining details of said new failure, wherein said details include at least an indication of the new failure itself and one operating condition parameter which was present when the new failure occurred;

recalling details of any stored previous failure;

comparing the details of said new failure to the recalled details of the previous failure; and

storing the details of said new failure only if the details of said new failure are different from the recalled details of the previous failure.

7. A method, for diagnosing a vehicle failure, as claimed in claim 6, wherein said new failure is detected upon turning ON a vehicle power supply.

8. A method, for diagnosing a vehicle failure, as claimed in claim 7, wherein said recalled details of the previous failure were stored upon a previous turning OFF of said vehicle power supply.

9. A method, for diagnosing a vehicle failure, comprising the steps of:

determining an occurrence of any previous failure;

recalling details of said previous failure, wherein said details include at least an indication of the previous failure itself and one operating condition parameter which was present when the previous failure occurred;

determining an absence of any new failures which have details matching the recalled details of said previous failure; and

determining that a repair of said previous failure has occurred and normal operation has been restored.

10. A method, for diagnosing a vehicle failure, comprising the steps of:

turning ON a vehicle power supply;

detecting any new failure;

recalling details of any stored previous failure, wherein said details include at least an indication of the previous failure itself and one operating condition parameter which was present when the previous failure occurred;

determining that said new failure existed when said vehicle power supply was previously turned OFF by comparing details of the new failure with the recalled details of the previous failure; and

determining to store details of said new failure only if the new failure has different details as compared to the recalled details of the previous failure.

11. A method, for diagnosing a vehicle failure, comprising the steps of:

determining an occurrence of any previous failure;

recalling details of said stored previous failure, wherein said details include at least an indication of said previous failure itself and one operating condition parameter which was present when said previous failure occurred;

determining a first time, which is an amount of time that elapsed, during which said previous failure was being detected;

determining a second time, which is an amount of time that elapsed, subsequent to storing said previous failure, during which there was the absence of detection of any new failures with details matching the recalled details of said previous failure; and

determining that a repair of said previous failure has occurred when the second time is greater than the first time.