Reading and Clearing Diagnostic Trouble Codes

The on-board diagnostic system can be used to help determine charging system malfunctions. This system monitors, then stores information that can be retrieved by using a DRBII diagnostic tool. Install DRBII on vehicle, refer to DIAGNOSIS AND TESTING PROCEDURES/DIAGNOSTIC CHARTS for proper code diagnostic procedure.
If a diagnostic tool is not available, the trouble codes can be retrieved by using the "Check Engine" lamp on the instrument cluster. Cycle the ignition switch On-Off-On-Off-On-Off-On without starting the engine. The light will go on for two seconds as a bulb check, immediately following this will be the trouble code. Count the number of flashes, for example flash, pause, flash, flash is trouble code 12. Refer to DIAGNOSIS AND TESTING PROCEDURES/DIAGNOSTIC CHARTS for trouble codes and trouble code diagnosis. All trouble codes are two digit numbers with a four second pause between different codes.