Transmission Fluid Heater Coolant Control Valve
WARNING: This page is about a different car, the 2021 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
The transmission fluid heater coolant control valve is an electrically controlled solenoid to allow or bypass the flow of engine coolant through the transmission fluid warmer or transmission fluid cooler depending on vehicle application. This electrically controllable valve is normally open when not energized. The valve receives a fused 12V B+ supply when the ignition is in the run or start position and is grounded by the PCM via a low side driver. The PCM monitors the solenoid and circuits for electrical faults and sets an appropriate DTC.