Clearing Diagnostic Trouble Codes

Use a scan tool to clear DTCs from the PCM memory. Disconnecting the vehicle battery to clear the PCM memory is not recommended. This may or may not clear the PCM memory, and other vehicle system memories will be cleared. Do not disconnect the PCM connectors solely for clearing the DTCs. This unnecessarily disturbs the connections and may introduce a new problem. Before clearing the DTCs the scan tool has the capability to save any data stored with the DTCs and then display that data at a later time. Capture the DTC info before beginning a diagnosis. Refer to Capturing DTC Info. Do not clear the DTCs until you are instructed to do so within a diagnostic procedure.

Many PCM DTCs have complex test and failure conditions. Therefore, simply clearing the DTCs and determining if the DTC sets again may not indicate whether a problem has been corrected. To verify a repair after service is complete, you must look up the test conditions and duplicate those conditions. If the DTC runs and passes, chances are good that the problem is fixed.