Transmission Control Switch (TCS)

WARNING: This page is about a different car, the 2003 Lincoln Aviator. However, it is still accessible from the selected car via links, so may be relevant.

The transmission control switch (TCS) is a momentary contact switch that allows the driver to cancel operation of fifth ((D)) gear.

The TCS is located on the selector lever handle.

When the driver initially presses the TIS a signal is sent to the powertrain control module (PCM).

The PCM uses the shift solenoids to disengage/disable fifth gear operation and activate the coast clutch.

At the same time, the PCM illuminates the transmission control indicator lamp (TCIL) to notify the driver that 5th gear is canceled.

When the TIS is pressed again, fifth ((D)) gear operation is enabled, the coast clutch is released and the TAIL is turned off.

Whenever the ignition is cycled (vehicle shut off, then started again), the TCS is turned off and fifth gear will be enabled, even if the TCS had been on when the ignition was shut off.