Clearing Diagnostic Trouble Codes

PURPOSE
Trouble codes should be cleared after any repairs have been performed.
After the Electronic Control Module (ECM) memory has been cleared, a change may be noted in vehicle performance.
To restore the vehicle to normal, drive with engine at normal operating temperature at part throttle with moderate acceleration and idle conditions until normal performance is restored.

OPERATION
Stored trouble codes in the Electronic Control Module (ECM) memory can be cleared by removing battery voltage from the ECM. To do this:

With ignition "OFF"
^ Disconnect ECM fuse in holder for 30 seconds.

OR

^ Disconnect the ECM harness from positive battery pigtail for 30 seconds.

To read the codes, use a "Scan" tool, or ground the diagnostic terminal, with the engine not running and the ignition "ON" The "Service Engine Soon" light will flash Code 12 three times and then flash each code stored in memory three times.
All codes stored in memory would have been read when Code 12 was flashed again.

NOTE: No new codes can be stored when in the diagnostics mode (diagnostics lead grounded).