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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Automatic Transmission





The automatic transmission control module (TCM) provides the engine control module (ECM) with the following information:

^ gear selector in P/N or drive positions.
^ that a gear-change is imminent.
^ request to operate the malfunction indicator lamp (MIL).

The engine control module can reduce engine torque just before gear-shifting. Timing is retarded for a maximum of one second.

The control module is located in the passenger compartment.