GLOW PLUG CONTROL DUAL MODE FAULT DIAGNOSTICS

• US 20090323250A1
• Filed: 08/08/2008
• Published: 12/31/2009
• Est. Priority Date: 06/27/2008
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Thompson, Brett B.
• Granted Patent: US 8,131,416 B2
• Time in Patent Office: Days
• US Class Current: 361/264
• CPC Class Codes: F02P 17/00 Testing of ignition installations, e.g. in combination with adjusting testing fuel injection apparatus F02M65/00; testing ignition installations in general F23Q23/00; Testing of ignition timing in compression-ignition engines
• CPC Class Codes: F02P 19/027 Safety devices, e.g. for diagnosing the glow plugs or the related circuits

Abstract

A glow plug control system for a vehicle comprises a mode control module and a fault diagnostic module. The mode control module enables one of a first mode and a second mode of operation based on a period of time that a glow plug is ON during a drive cycle. The fault diagnostic module selectively diagnoses a fault based on a first message, a second message, and a third message when the first mode is enabled and selectively diagnoses the fault independent of the second and third messages when the second mode is enabled.

Claims

1. A glow plug control system for a vehicle, comprising:

a mode control module that enables one of a first mode and a second mode of operation based on a period of time that a glow plug is ON during a drive cycle; and

a fault diagnostic module that selectively diagnoses a fault based on a first message, a second message, and a third message when said first mode is enabled and that selectively diagnoses said fault independent of said second and third messages when said second mode is enabled.

2. The glow plug control system of claim 1 wherein said mode control module enables said second mode of operation when said glow plug is ON for a threshold period of time during said drive cycle.

3. The glow plug control system of claim 1 wherein said first message includes engine speed data.

4. The glow plug control system of claim 1 wherein said second message includes mass airflow (MAF) data.

5. The glow plug control system of claim 1 wherein said third message includes intake air temperature data.

6. The glow plug control system of claim 1 wherein fault diagnostic module diagnoses said fault when at least one of said first, second, and third messages is absent for a first predetermined period of time while said first mode is enabled.

7. The glow plug control system of claim 6 wherein said fault diagnostic module diagnoses said fault when said first message is absent for a second predetermined period of time while said second mode is enabled.

8. The glow plug control system of claim 7 wherein said second predetermined period is greater than said first predetermined period.

9. A method comprising:

enabling one of a first mode and a second mode of operation based on a period of time that a glow plug is ON during a drive cycle;

selectively diagnosing a fault based on a first message, a second message, and a third message when said first mode is enabled; and

selectively diagnosing said fault independent of said second and third messages when said second mode is enabled.

10. The method of claim 9 wherein said enabling one of said first mode and said second mode comprises enabling said second mode of operation when said glow plug is ON for a threshold period of time during said drive cycle.

11. The method of claim 9 wherein said first message includes engine speed data.

12. The method of claim 9 wherein said second message includes mass airflow (MAF) data.

13. The method of claim 9 wherein said third message includes intake air temperature data.

14. The method of claim 9 wherein said selectively diagnosing said fault based on a first message, a second message, and a third message comprises diagnosing said fault when at least one of said first, second, and third messages is absent for a first predetermined period of time while said first mode is enabled.

15. The method of claim 14 wherein said selectively diagnosing said fault independent of said second and third messages comprises diagnosing said fault when said first message is absent for a second predetermined period of time while said second mode is enabled.

16. The method of claim 15 wherein said second predetermined period is greater than said first predetermined period.