780 V6-2849cc 2.8L SOHC B280F (1987)
Coolant Temperature Sensor/Switch (For Computer): Description and Operation
Coolant Temperature Sensor
PURPOSE
The coolant temperature sensor provides both ECUs with information regarding the engine temperature for proper adjustment of injection duration
and ignition timing.
LOCATION
Front of engine, under intake manifold.
CONSTRUCTION
The coolant temperature sensor is an NTC (negative temperature coefficient) type. This means the higher the coolant temperature, the lower the
sensor resistance.
OPERATION
The ECU applies constant voltage to the sensor and monitors the voltage in the circuit. As temperature increases, sensor resistance decreases
causing a decrease in the measured voltage of the circuit. By monitoring the circuit voltage, the ECU calculates engine temperature and adjusts the
air/fuel ratio and ignition timing to meet the specific demands of the engine.
