Test NTC-4A - Checking Coolant Sensor Calibration & Radiator Fan Operation

WARNING: This page is about a different car, the 1995 Plymouth Voyager, 1995 Plymouth Grand Voyager, 1995 Dodge Grand Caravan, and 1995 Dodge Caravan. However, it is still accessible from the selected car via links, so may be relevant.

Start engine. Using scan tool, read Engine Coolant Temperature (ECT) sensor value. If ECT sensor temperature is more than 180°F (82°C), stop engine. Allow engine coolant to cool to 150°F (66°C). Start engine. Allow engine to reach normal operating temperature of 180°F (82°C). If ECT sensor value does not increase smoothly, replace ECT sensor. Perform TEST VER-2. If ECT sensor value increases smoothly, go to next step.
If ECT sensor value does not reach 180°F (82°C) or more, replace ECT sensor. Perform TEST VER-2. If ECT sensor value reaches 180°F (82°C) or more, run engine until radiator fan operates or ECT sensor value reaches 220°F (104°C). If cooling fan does not operate, repair cooling fans as necessary. Perform TEST VER-2. If cooling fan operates, system is functioning properly. Test is complete.