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Coolant Temperature Sensor/Switch (For Computer): Description and Operation



Cylinder Head Temperature Sensor (CHT)

Engine Views:






AllData Editor's Note:
"Ford provides conflicting information regarding usage of an Engine Coolant Temperature (ECT) sensor for this vehicle/engine. While service and repair information indicates use of a Cylinder Head Temperature (CHT) sensor, the diagnostic procedures and wiring diagrams indicate a coolant temperature sensor is used on this model/engine combination."

From the Powertrain Control/Emissions Diagnosis OBDII Manual:

On applications that do not use a ECT sensor, the CHT sensor is used to determine the engine coolant temperature in place of the ECT sensor. In this case the PCM may store both CHT and ECT Diagnostic Trouble Codes (DTCs). To cover the entire temperature range of both the CHT and ECT sensors, the PCM has a dual switching resistor circuit on the CHT input.


For Cylinder Head Temperature (CHT) Sensor refer to: "Powertrain Management : Computers and Control Systems : Engine Temperature Sensor" Engine Temperature Sensor