Radiator Cooling Fan Motor: Testing and Inspection

ON-VEHICLE INSPECTION

HINT: It is normal that the cooling fan sometime rotates when the ignition switch is turned from ACC to ON.

1. CHECK COOLING FAN OPERATION WITH LOW TEMPERATURE (Below 83°C (181°F))
a. Turn the ignition switch ON.
b. Check that the cooling fan stops.
If not, check the cooling fan relay and water temperature switches, and check for disconnection of connectors or wire break between the cooling fan relay and water temperature switches.
c. Disconnect the water temperature switch No. 1 connector.
d. Connect terminals on the water temperature switch No.1 connector.
e. Check that the No.1 cooling fan rotates at high speed.
If not, check the No.1 cooling fan relay and No.1 cooling fan.
f. Reconnect the water temperature switch No.1 connector.
g. Disconnect the water temperature switch No.2 connector.
h. Ground terminal on the water temperature switch No.2 wire harness side connector.
i. Check that the No. 1 and No.2 cooling fans rotate at low speed.
If not, check the No.2 cooling fan relay, No.3 cooling fan relay and No.2 cooling fan.
j. Reconnect the water temperature switch No.2 connector
2. INSPECT COOLING FAN
a. Disconnect the cooling fan connector.
b. Connect battery and ammeter to the cooling fan connector.
c. Check that the cooling fan rotates smoothly, and check the reading on the ammeter.
Standard amperage: 8.0 - 12.0 A at 20°C (68°F)
d. Reconnect the cooling fan connector.

INSPECTION





1. COOLING FAN RELAY
COOLING FAN RELAY NO.3
a. Inspect the cooling fan relay continuity.
1) Using an ohmmeter, check that there is continuity between terminals 1 and 2.
If there is no continuity, replace the relay.
2) Check that there is no continuity between terminals 3 and 5.
If there is continuity, replace the relay.
3) Apply battery voltage across terminals 1 and 2.
4) Using an ohmmeter, check that there is continuity between terminals 3 and 5.
If there is no continuity, replace the relay.





2. COOLING FAN RELAY NO.2
a. Inspect the cooling fan relay continuity.
1) Using an ohmmeter, check that there is continuity between terminals 1 and 2.
If there is no continuity, replace the relay.
2) Using an ohmmeter, check that there is continuity between terminals 3 and 4.
If there is no continuity, replace the relay.
3) Check that there is no continuity between terminals 3 and 5.
If there is continuity, replace the relay.
4) Apply battery voltage across terminals 1 and 2.
5) Using an ohmmeter, check then there is continuity between terminals 3 and 5.
If there is no continuity, replace the relay.





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





4. TEMPERATURE DETECT SWITCH NO.2
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 no continuity, replace the switch.
b. Check that there is no continuity, between terminals when the coolant temperature is below 83°C (181°F).
If there is continuity, replace the switch.