Cruise Control Electronic Control Unit (ECU)

Cruise control unit delivers an input signal to control overdrive operation in accordance with vehicle speed when cruise control is operating. When in overdrive with cruise control on, if vehicle speed drops 2 MPH less than the set speed, overdrive is released to prevent reduction in vehicle speed. Once vehicle speed is more than the set speed, the overdrive is resumed. If coolant temperature is low, transmission will not shift into overdrive. Cruise control unit is located next to TCM. See Figure.