Transmission Control (TC) Switch
WARNING: This page is about a different car, the 2009 Mercury Mountaineer, 2009 Ford Explorer Sport Trac, and 2009 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
The transmission control (TC) switch is a momentary contact switch located on the selector lever knob. Pushing the TC switch will either disengage or engage the overdrive function of the transmission. If OVERDRIVE is disengaged, the message O/D OFF will illuminate on the instrument panel.