Clearing Codes

In the process of controlling the various subsystems, the ECM and BCM continually monitor operating conditions for possible malfunctions. By comparing system conditions against standard operating limits certain circuits and component malfunctions can be detected. A three digit numerical code is stored in the computer memory when a problem is detected by this self diagnostic system.

The trouble codes stored in the system memory can be cleared to aid in diagnosing intermittent conditions. To clear codes, proceed as follows:
1. Enter diagnostic service mode as outlined.
2. Follow steps 1 and 2 under DIAGNOSTIC TEST PROCEDURES.
3. Depress LO button on the CCP until clear codes is displayed.
4. Depress HI button on the CCP, this will start the erasing process. Note the following.
a. Selection of the clear codes test type will result in the message clear codes being displayed along with the selected system name. This message will appear for 3 seconds to indicate that all stored trouble codes have been erased from that system's memory. After 3 seconds the display will automatically return to the next available test type for the selected system.