Radiator Cooling Fan Temperature Sensor / Switch: Testing and Inspection

1. Drain engine coolant.





2. Remove Engine Coolant Temperature (ECT) switches.





3. Inspect No. 1 ECT switch.
(a) Using an ohmmeter, check that there is no continuity between the terminals when the coolant temperature is above 98° C (208° F).
If there is continuity, replace the switch.
(b) Using an ohmmeter, check that there is continuity between the terminals when the coolant temperature is below 88° C (190° F).
If there is no continuity, replace the switch.





4. Inspect No. 2 ECT switch.
(a) Using an ohmmeter, check that there is continuity between the terminals when the coolant temperature is above 93° C (199° F).
If there is continuity, replace the switch.
(b) Using an ohmmeter, check that there is no continuity between the terminals when the coolant temperature is below 83° C (181° F).
If there is no continuity, replace the switch.
5. Reinstall ECT switches.
6. Refill with engine coolant.