Transmission Control Switch (TCS) and Transmission Control Indicator Lamp (TCIL)

The Transmission Control Switch (TCS) is located inside the end of the selector lever. For vehicles equipped with a 4R75E, pushing the TCS will either disengage or engage the Overdrive (O/D) function of the transmission. When O/D is disengaged, the Transmission Control Indicator Lamp (TCIL) will illuminate T/C OFF on the Instrument Cluster (IC). Each time the ignition switch is cycled, the transmission will automatically provide O/D operation regardless of TCS position the last time the vehicle was running.