ELECTRONIC CONTROL APPARATUS HAVING SELF-DIAGNOSIS FUNCTION

• US 20080201035A1
• Filed: 02/07/2008
• Published: 08/21/2008
• Est. Priority Date: 02/16/2007
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kondoh, Masayoshi, Shimizu, Koukichi
• Granted Patent: US 8,095,257 B2
• Time in Patent Office: Days
• US Class Current: 701/33
• 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 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 said first function detects an abnormality in an M-th (M being an integer larger than 1 and not larger than said N), storing an abnormality code indicative of said detected abnormality in said rewritable nonvolatile memory;

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

2. The electronic control apparatus according to claim 1, wherein said items are components 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 further comprises 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, identify said abnormality code indicating said M-th item and said identification information associated with said M-th item from abnormality codes and identification information stored in said rewritable nonvolatile memory on the basis of said identification information associated with said M-th item, and erasing said M-th item and said identification information associated with said M-th item from said nonvolatile memory.

3. The electronic control apparatus according to claim 2, 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 abnormality and to start said count operation in a second direction opposite to said first direction when said first function detects absence of 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 times.

4. The electronic control apparatus according to claim 1, further comprising a third function of storing therein relationships between each of said first to said N-th items and identification information to identify said each of said first to said N-th items, said second function being configured to obtain said identification information indicating said M-th item from said relationships stored in said third function, and to store said obtained identification information in said rewritable nonvolatile memory together with said abnormality code.

5. The electronic control apparatus according to claim 4, wherein said second function is configured to store a code containing information about said abnormality code and said identification information associated with said M-th item in said rewritable nonvolatile memory in place of said abnormality code and said identification information associated with said M-th item, said third function being configured to store therein also a relationship between said code and said abnormality code, said electronic control apparatus further comprising a fourth function of restoring said abnormality code from said conversion/abnormality code by referring to said relationship stored in said rewritable nonvolatile memory, and outputting said restored abnormality code in response to a request from an external diagnostic tool.

6. The electronic control apparatus according to claim 2, wherein said identification information is uniquely associated with each of said first to N-th item.

7. The electronic control apparatus according to claim 2, wherein two or more of said first to N-th items is assigned to the same abnormality code, and said identification information is uniquely associated with each of said two or more of said first to N-th items.

8. The electronic control apparatus according to claim 2, further comprising a memory in which said abnormality code is stored, storage address of said memory being predetermined such that each said identification information indicating each said item is a storage address thereof in said a memory.

9. The electronic control apparatus according to claim 1, wherein said rewritable nonvolatile memory is provided in an external device connected to said electronic control apparatus.