Component Testing

1. Using a suitable ohmmeter, check thermo control switch, located on water inlet housing, as follows:
a. Check that continuity is not present when water temperature is below 146°F.
b. Ensure continuity exists when the coolant temperature is above 212°F.
c. If continuity checks are not as specified, replace switch.

Fig. 1 Checking Cooling Fan Motor Relay.:

2. Inspect cooling fan motor relay, located in engine compartment relay box as follows:
a. Using a suitable ohmmeter, check if continuity exists between terminals 1 and 2, Fig. 1.
b. Using a suitable ohmmeter, ensure no continuity exists between terminals 1 and 3 and between terminals 1 and 4, Fig. 1.
c. Using a suitable ohmmeter, ensure no continuity exists between terminals 2 and 3 and between terminals 2 and 4, Fig. 1.
d. If continuity checks are not as specified, replace relay.

Fig. 2 Checking Fan Motor.:

3. Using a suitable ammeter and battery, connect fan motor connector, Fig. 2. Ensure motor rotates smoothly and current draw is 5.0-8.0 amps.