Control Module: Description and Operation

The Transmission Control Switch (TCS) is a momentary contact switch. When the switch is pressed, a signal is sent to the Powertrain Control Module (PCM) to allow automatic shifts from first through third gears only, locking out fourth gear (OVERDRIVE). The powertrain control module then energizes the transmission control indicator lamp on the instrument cluster to indicate OVERDRIVE OFF.

The Transmission Control Switch (TCS) is located in the transmission control selector dial bezel. This system automatically engages into the OVERDRIVE mode each time the ignition switch is turned to RUN.