Coolant Temperature Sensor (CTS)

The CTS is mounted in engine coolant stream of intake manifold. This sensor is a thermistor which changes resistance based on coolant temperature. Sensor provides coolant temperature information to ECM for fuel enrichment, ignition timing, EGR operation, canister purge control, air management, idle speed control, and closed loop fuel control.

Sensor resistance will be high with cold coolant temperatures and low with hot coolant temperatures.