Accessing 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.

After the diagnostic service mode is entered, any trouble codes stored in the computer memory will be displayed, refer to SYSTEM DIAGNOSTIC CHARTS. ECM codes will be displayed first, then BCM codes. Codes will also be accompanied by Current or History. History indicates the failure was not present the last time the code was tested. Current indicates the fault still exists. At any time during the display of trouble codes the Low button on the CCP is depressed, the display of codes will be bypassed. At any time during the display of trouble codes the Reset/Recall button on the DIC is depressed, the system will exit diagnostic service mode and go back to normal vehicle operation. For 1989-90 models refer to SYSTEM DIAGNOSTIC CHARTS, for the following trouble codes:
Code EO60
Code EO63
Code EO64
Code EO65
Code EO66
Code EO67
Code EO68
For 1991 models refer to SYSTEM DIAGNOSTIC CHARTS, for the following trouble codes:
Code EO60
Code EO61
Code EO62
Code EO63
Code EO64
Code EO65
Code EO66
Code EO67
Code EO68