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Clearing Codes: Notes

Hard and intermittent fault codes remain in ECM memory until battery voltage is removed from the ECM. Removing battery voltage to the ECM for 30 seconds will clear all stored memory codes. Codes should be cleared from memory when repair is complete. Some diagnostic flow charts require that a code be cleared during testing. Battery voltage may be removed from the ECM by disconnecting the battery, the ECM harness connector, or fuse F-10 (10 amp).

CAUTION: Ensure ignition switch is in the "OFF" position when disconnecting or reconnecting battery power to the ECM.
NOTE: When battery power is disconnected from the ECM to clear codes, computer memory will be erased. A change in vehicle performance and driveability may be noted while the ECM "relearns" driving conditions. For additional information on this process, see THEORY/OPERATION article.