Clearing Diagnostic Trouble Codes

On Board Diagnostic Flow Chart (Part 1 of 2):

On Board Diagnostic Flow Chart (Part 2 of 2):

NOTE: For the purpose of the test, the diagnostic procedures may refer to the Powertrain Control Module (PCM) as the ECM or Engine Control Module.

OPERATING SELF-DIAGNOSTIC SYSTEM TO CLEAR PCM CODES


To enter diagnostic mode, proceed as follows:

1. Turn ignition "ON".

2. Depress the "OFF" and "WARMER" buttons on the Electronic Climate Control (ECC) simultaneously and hold until the segment check appears on the Instrument Panel Control (IPC).

3. Wait for the segment check to take place.

4. After trouble codes have been displayed, "ECM?" will be displayed. Depress the "HI" button on the ECC to bring up "ECM DATA?".

5. Cycle through the Displays by depressing "LO" on the ECC until "ECM CLEAR CODES" is displayed.

6. Depress the "HI" button on the ECC to clear PCM codes.

7. Get out of diagnostic mode by depressing "RESET/RECALL" button, or turn the ignition switch "OFF".


EXITING DIAGNOSTIC MODE

To get out of the diagnostic mode at any time during the test, depress the "RESET" button on the DIC, or turn the ignition switch "OFF". Any trouble codes not previously erased are not erased when this is done.




NOTES:

The ECM clear codes option may be used to clear stored PCM trouble codes. When selected, the ECM clear codes option immediately erases all codes stored up to that point and causes the IPC to display "ECM CODES CLEAR". Once a problem has been corrected, it is a good idea to clear codes so that any future service work is not needlessly confused.

Many PCM codes have complex test and failure conditions. Therefor, simply clearing codes, exiting diagnostics, and watching to see is the code sets again may not indicate whether a problem has been corrected. Test conditions vary greatly by individual codes. If the code does not reappear after meeting the test conditions, chances are good that the problem is fixed.