Electronic control apparatus having self-diagnosis function

• US 8,095,257 B2
• Filed: 02/07/2008
• Issued: 01/10/2012
• Est. Priority Date: 02/16/2007
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kondoh, Masayoshi, Shimizu, Koukichi
• Primary Examiner(s): Jayne, Darnell
• Assistant Examiner(s): Buc, Steven M.
• Application Number:
  US12/068,537
• Publication Number:
  US 20080201035A1
• Time in Patent Office: 1,433 Days
• Field of Search: 701/29, 701/31
• US Class Current: 701/29
• CPC Class Codes: F02D 2041/228 Warning displays
• CPC Class Codes: F02D 41/107 and deceleration
• 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: F02D 41/222 relating to the failure of sensors or parameter detection devices
• CPC Class Codes: F02D 41/2487 Methods for rewriting
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

The electronic control apparatus includes a rewritable nonvolatile memory, a first function of performing a monitoring operation to detect abnormalities in each of a first to N-th (N being an integer larger than 2) items, and a second function of, when the first function detects an abnormality in an M-th (M being an integer larger than 1 and not larger than the N), storing an abnormality code indicative of the detected abnormality in the rewritable nonvolatile memory. The second function is configured to store an identification information associated with the M-th item so that the M-th item can be identified from the first to N-th items in the rewritable nonvolatile memory.

Claims

1. An electronic control apparatus comprising:

a rewritable nonvolatile memory;

a monitoring means for monitoring a first item and a second item; and

an abnormality storing means configured (a) to store, when said monitoring means detects an abnormality in said first item, identification information identifying said first item and a diag code representing a type of said abnormality detected in said first item in said rewritable nonvolatile memory, and (b) to store, when said monitoring means detects an abnormality in said second item, identification information identifying said second item and a diag code representing a type of said abnormality detected in said second item in said rewritable nonvolatile memory so that said first item and its respectively corresponding diag code is uniquely identifiable from said second item and its respectively corresponding diag code based on data stored in said rewritable nonvolatile memory.

7. The electronic control apparatus according to claim 1, wherein said identification information is stored in association with each of said first to Nth items.

8. The electronic control apparatus according to claim 1, wherein two or more of said first to N-th items are assigned the same abnormality diag code, and the identification information separately associated with each of said two or more of said first to N-th items uniquely identifies each of said two or more of said first to N-th items.

2. An electronic control apparatus comprising:

a rewritable nonvolatile memory; and

a data processor configured to effect

(a) a first function of performing a monitoring operation to detect abnormalities in each of first to Nth items, N being an integer larger than or equal to 2;

and

(b) a second function of, when said first function detects an abnormality in an M-th item, M being an integer larger than or equal to 1 and not larger than said N, storing an abnormality diag code indicative of said abnormality in said rewritable nonvolatile memory, said abnormality diag code being assigned in common to said first to N-th items;

wherein said second function is configured to store identification information uniquely associated with said M-th item so that said M-th item is capable of being uniquely identified from said first to N-th items in said rewritable nonvolatile memory.

3. The electronic control apparatus according to claim 2, wherein:

said data processor is mounted on a vehicle,

said first function is configured to perform said monitoring operation in each trip period of said vehicle, and

said electronic control apparatus is further configured to effect a third function of, when said first function makes a determination of said M-th item having recovered to normality in a predetermined number of consecutive said trip periods, identifying said abnormality diag code indicating said M-th item and said identification information uniquely associated with said M-th item from other abnormality diag codes and identification information stored in said rewritable nonvolatile memory based on said identification information associated with said M-th item, and erasing data representing said M-th item and said identification information associated with said M-th item from said nonvolatile memory.

4. The electronic control apparatus according to claim 3, further comprising:

a counter provided for each said first to N-th items, said counter being configured to start a count operation in a first direction when said first function detects presence of an abnormality and to start said count operation in a second direction opposite to said first direction when said first function detects absence of an abnormality, said count operation being performed once in each said trip period,

said third function being configured to determine that said M-th item has recovered to normality if said counter provided for said M-th item has performed said count operation in said second direction for said predetermined number of consecutive said trip periods.

5. The electronic control apparatus according to claim 2, wherein said processor is further configured to effect:

a third function of storing data representing relationships between each of said first to said N-th items and identification information to uniquely identify said each of said first to said N-th items,

said second function being configured to derive said identification information uniquely indicating said M-th item based on said data representing relationships as previously stored by said third function, and to store said derived identification information in said rewritable nonvolatile memory together with said abnormality diag code.

6. The electronic control apparatus according to claim 5, wherein:

said second function is configured to store a further code containing information about said abnormality diag code and said identification information associated with said M-th item in said rewritable nonvolatile memory in place of said abnormality diag code and said identification information associated with said M-th item,

said third function being configured to also store data representing a relationship between said further code and said abnormality diag code,

said processor being configured to effect a fourth function of restoring said abnormality diag code by referring to said data representing a relationship stored in said rewritable nonvolatile memory, and outputting a restored abnormality code in response to a request from an external diagnostic tool.

9. The electronic control apparatus according to claim 3, further comprising:

a memory in which said abnormality diag code is stored, a storage address of said memory in which each abnormality diag code is stored being predetermined such that said identification information associated with each said item is a storage address thereof in said memory.

10. The electronic control apparatus according to claim 2,

wherein:

said rewritable nonvolatile memory is disposed in an external device connected to said processor.