Impreza L Sedan F4-2.2L SOHC (1997)
Coolant Temperature Sensor/Switch (For Computer): Description and Operation
Coolant Temperature Sensor
PURPOSE
The ECM uses engine temperature information to calculate the following:
^ Injection quantity
^ Ignition timing
^ Canister purge
^ Idle speed
^ Radiator fan operation
Coolant Temperature Sensor Range Chart
OPERATION
The coolant temperature sensor contains a thermistor whose resistance changes with the temperature. The ECM sends a reference voltage to the
sensor and measures changes in resistance as the engine temperature varies.
