Engine - Coolant Temperature Sensor/Switch: Testing and Inspection

Fig. 51 Coolant Temp. Sensor Resistance Values:

Coolant temperature sensor test.
a. With the engine off, unplug the coolant temp. sensor and check resistance between sensor and ground. Refer to Fig. 51, for readings at specific coolant temps.
b. Test resistance at two temperatures. Example:
+20°C (68°F) 2.2 - 2.8 K Ohms
+80°C (176°F) 290 - 364 Ohms
+100°C (212°F) 140 - 220 Ohms
c. If resistances are not within specifications, replace the sensor.