Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Control Module: Service Precautions

Precautions





- Before connecting or disconnecting the TCM/PCM harness connector turn ignition switch OFF and disconnect negative battery terminal. Failure to do so may damage the TCM/PCM. Because battery voltage is applied to TCM/PCM even if ignition switch is turned off.





- When connecting or disconnecting pin connectors into or from TCM/PCM, take care not to damage pin terminals (bend or break).
Make sure that there are not any bends or breaks on TCM/PCM pin terminal, when connecting pin connectors.





- Before replacing TCM/PCM, perform TCM/PCM input/output signal inspection and make sure whether TCM/PCM functions properly or not.





- After performing each TROUBLE DIAGNOSIS, perform "DTC (Diagnostic Trouble Code) CONFIRMATION PROCEDURE". The DTC should not be displayed in the "DTC CONFIRMATION PROCEDURE" if the repair is completed.