Expedition 4WD V8-281 4.6L SOHC (1998)
Overdrive Switch: Description and Operation
TRANSMISSION CONTROL SWITCH (TCS) AND TRANSMISSION CONTROL INDICATOR LAMP (TCIL)
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 fourth gears or first through third gears only. The PCM energizes the Transmission Control
Indicator Lamp (TCIL) when the switch is off. The TCIL indicates overdrive cancel mode activated (lamp on) and Electronic Pressure Control (EPC)
circuit shorted (lamp flashing) or monitored sensor failure.
