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: 2.1 - 2.9 K ohms
TEMPERATURE: 122°F (50°C)
Resistance: .68 - 1.0 K ohms
TEMPERATURE: 176°F (80°C)
Resistance: 0.30 - 0.33 K ohms


Replace the sensor if it fails the above test.