Transmission Control Switch (TCS)
On automatic transmission equipped vehicles, the TCS provides an input signal to the PCM whenever the switch is pressed. For F-Super Duty, the tow/haul indicator illuminates when the TCS is cycled to engage and disengage the tow/haul strategy. For E-Series, the overdrive cancel indicator illuminates when the TCS is cycled to engage or disengage the overdrive function of the transmission. For additional information and diagnostics, refer to the appropriate AUTOMATIC TRANSMISSION article.