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Clearing Trouble Codes

NOTE: To prevent ECM damage, ensure ignition is in OFF position when disconnecting or reconnecting power to ECM.

Trouble codes should be cleared after repairs have been completed. Also, some diagnostic charts require codes to be cleared before using diagnostic chart. To clear codes, remove power to ECM for 30 seconds by either disconnecting battery cable and ECM pigtail to battery, or removing ECM "B" fuse.

If no hard fault codes are present (only intermittent codes exist), proceed to TESTS W/O CODES article in this section for intermittent diagnostic procedures.

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