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Home >> GMC >> 2002 >> C3500 HD 8.1 G, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - 8.1L >> Repair Instructions >> Powertrain Control Module (PCM) Replacement >> Notes
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Powertrain Control Module (PCM) Replacement: Notes

Service of the powertrain control module (PCM) should normally consist of either replacement of the PCM or electrically erasable programmable read only memory (EEPROM) programming. If the diagnostic procedures call for the PCM to be replaced, the PCM should be inspected first to see if the correct part is being used. If the correct part is being used, remove the faulty PCM and install the new service PCM.

Important:  To prevent internal PCM damage, the ignition must be OFF when disconnecting or reconnecting power to the PCM. For example, when working with a battery cable, PCM pigtail, PCM fuse, or jumper cables.

Important:  Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM module connector gaskets when diagnosing or replacing the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent contaminant intrusion into the PCM.

Important:  The replacement PCM must be programmed.