Abnormality detection method and system having sleep mode check function

• US 6,958,976 B2
• Filed: 06/11/2001
• Issued: 10/25/2005
• Est. Priority Date: 07/27/2000
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Kishigami, Tomohisa, Sato, Jiro, Senoo, Shinichi, Kikkawa, Hajime
• Primary Examiner(s): Nguyen, Brian
• Assistant Examiner(s): Phan, Tri H.
• Application Number:
  US09/877,079
• Publication Number:
  US 20020012325A1
• Time in Patent Office: 1,597 Days
• Field of Search: 370241-251, 370/311, 701 29- 35, 340/901, 340/425.5, 340/438, 340/506
• US Class Current: 370/241
• CPC Class Codes: B60W 50/04 Monitoring the functioning of the control system
• CPC Class Codes: H04L 41/0677 Localisation of faults
• CPC Class Codes: H04L 43/00 Arrangements for monitoring or testing data switching networks

Abstract

A plurality of electronic control units is continuously supplied with electric power to be capable of communication one another even when respective controlled devices are in inoperative condition. Each ECU transmits a sleep NG information along with its device ID when it not allowed to remain in the sleep mode. An abnormality detection unit connected to the ECUs through communication lines monitors the sleep NG information of each ECU to detect the ECU remaining activated for more than a wait period which is required for the ECU to shift to the sleep mode. The device ID of the ECU which is detected as remaining activated is stored in a memory so that any abnormal location may be specified by the stored device ID.

Claims

1. An abnormality detection system comprising:

a network including a plurality of electronic control units for respective controlled devices, the control units being constructed to transmit respective data frames;

a communication line; and

an abnormality detection unit connected to the network through the communication line for collecting abnormality monitor information of the controlled devices based on the transmitted data frames,

wherein the control units are constructed to shift to a sleep mode after a predetermined wait period under a condition that no activation cause is present,

wherein the control units are constructed to transmit, in the data frames, identification information thereof and sleep not good information indicative of sleep disablement when the activation cause is present, and

wherein the detection unit includes transition detection means for detecting a transition of the controlled devices from an operation condition to an operation stop, and activated unit detection means for monitoring the transmitted sleep not good information after the controlled devices shifted to the operation stop condition and detecting the control unit which remains activated after the predetermined wait period.

2. The abnormality detection system as in claim 1, wherein:

the detection unit further has memory means,

the activated unit detection means is constructed to monitor repeatedly the transmitted sleep not good information at every predetermined interval longer than the predetermined wait period for detecting the control unit remaining activated, and outputs the identification information of the activated control unit sequentially to the memory means to be stored therein as the abnormality monitor information.

3. The abnormality detection system as in claim 1, wherein:

the detection unit further has memory means for storing therein the identification information of the activated control unit as the abnormality monitor information.

4. The abnormality detection system as in claim 3, wherein:

the control units are constructed to transmit in the data frames, in addition to the sleep not good information, condition information indicative of operation of the controlled device which disables the sleep operation; and

the memory means stores the condition information as the abnormality monitor information.

5. The abnormality detection system as in claim 1, wherein:

the control units are programmed to control vehicle operations through the controlled devices mounted in a vehicle; and

the abnormality detection unit and the control units are continuously supplied with electric power from a battery irrespective of operation of a key switch of the vehicle, so that the control units and the abnormality detection unit are allowed to continuously communicate one another.

6. An abnormality detection method including a plurality of electronic control units for respective controlled devices and an abnormality detection unit connected to the control units through a communication line, the method comprising the steps of:

continuously supplying the control units and the detection unit with electric power to enable communication one another even when respective controlled devices are in operation stop condition;

transmitting a sleep information from each control unit along with its unit ID to indicate whether it is allowed to shift to a sleep mode from an activated mode;

monitoring the sleep information of each ECU to detect the control unit remaining activated for more than a wait period required for the control unit to shift to the sleep mode; and

storing the unit ID of the ECU which is detected as remaining activated so that any abnormal location may be specified by the stored unit ID, wherein

the monitoring step and the storing step are repeated at every predetermine interval longer than the wait period.

7. The abnormality detection method as in claim 6, wherein:

the supplying step, the transmitting step, the monitoring step and the storing step start after a key switch of a vehicle is turned off.