Engine - Coolant Temperature Sensor/Switch: Testing and Inspection

Engine Coolant Temperature Sensor Test:

Immerse sensor in water at specified temperatures and check resistance with an ohm meter.
Resitance should decrease as temperature increases.

TEMPERATURE: 68°F (20°C)
Resistance: 2.3 - 2.7 K ohms
TEMPERATURE: 94°F (90°C)
Resistance: .24 - 0.26 K ohms
TEMPERATURE: 230°F (110°C)
Resistance: 0.14 - 0.15 K ohms


Replace the sensor if it fails the above test.