General Diagnostic Information
As a bulb and system check, the Check Engine Light (CEL) and Stop Engine Light (SEL) will come on for five seconds when the ignition switch is first turned on. If the unit is programmed for the cruise control feature, the "Cruise Active" light (if equipped) will also turn on for five seconds.
If the CEL comes on during vehicle operation, it indicates the self diagnostic system has detected a fault.
When the diagnostic request switch is held, the diagnostic system will flash the yellow or red light located on the dash of the vehicle. The light will be flashing the code(s) indicating the problem areas. If the SEL comes on during vehicle operation, it indicates the DDEC System has detected a potential engine damaging condition. The engine should be shut down immediately and checked for the problem.
Active codes will be flashed on the SEL in numerical flash code order. If there are no active codes, a code 25 will be flashed.
Inactive codes will be flashed on the CEL in most recent to least recent order. If there are no inactive codes, a code 25 will be flashed.
|DDEC III/IV Single ECM Troubleshooting Guide - 6SE497
|Generated on 10-13-2008