9000 Hatchback L4-2290cc 2.3L DOHC Turbo EFI (1994)
Coolant Temperature Sensor/Switch (For Computer): Description and Operation
PRINCIPLE OF OPERATION, ENGINE COOLANT TEMPERATURE SENSOR
Engine coolant temperature sensor--is located in the intake manifold between the inlet pipes of cylinders 2 and 3 and is in communication with
the engine coolant. The sensor is of NTC type.
The control module measures the engine coolant temperature by applying 5 V to the sensor from pin 68 via a built-in 2.74 kohms resistor. The
sensor is grounded via pin 67 of the control module.
To ensure accurate temperature measurement, reference ground is supplied to pin 66 of the control module from the sensor ground lead. The
voltage across the resistor in the control module is proportional to the engine coolant temperature.
