Circuit Description
WARNING: This page is about a different car, the 2004 Suzuki Verona. However, it is still accessible from the selected car via links, so may be relevant.
The coolant temperature sensor (ECT) uses a thermistor to control the signal voltage to the engine control module (ECM).
he ECM supplies a voltage on the signal circuit to the sensor. When the air is cold, the resistance is high; therefore the ECT sensor signal voltage will be high. As the engine warms, the sensor resistance becomes less, and the voltage drops. At normal engine operating temperature, the voltage will be between 1.5 and 2.0 volts at the ECT sensor signal terminal. The ECT sensor is used to the following items:
- Fuel delivery.
- Lock Up Clutch (LUC).
- Ignition.
- Evaporative Emission (EVAP) Canister Purge Valve.
- Electric cooling fan.