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

Engine Coolant Temperature (ECT) Sensor:

PURPOSE
The Engine Coolant Temperature (ECT) sensor constantly supplies the Powertrain Control Module (PCM) with a signal reflecting engine coolant temperature.

OPERATION
The PCM uses this information for calculating the fuel injection amount. The ECT sensor also provides input to the PCM to control ignition timing, low/high speed cooling fan controls, Idle Air Control Bypass Air (IAC BPA) control, and emission controls.