Coolant Temperature Sensor / Switch HVAC: Testing and Inspection

1. DRAIN ENGINE COOLANT FROM
2. REMOVE ENGINE UNDER COVER
3. REMOVE ECT SWITCH




4. INSPECT ECT SWITCH CONTINUITY
a. Using an ohmmeter, check that there is no continuity between the terminals when the engine coolant temperature is above 93°C (199°F).
If there is continuity, replace the switch.
b. Using an ohmmeter, check that there is continuity between the terminals when the engine coolant temperature is below 83°C (181°F).
If there is no continuity, replace the switch.

5. INSTALL ECT SWITCH
a. Install the new O-ring to the switch.
b. Install the switch.

6. INSTALL ENGINE UNDER COVER
7. FILL WITH ENGINE COOLANT