Cooling System: Testing and Inspection
ON-VEHICLE INSPECTIONLow Temperature [below 83°C or 181°F]
1. TURN IGNITION SWITCH ON
Confirm that the fan stops.
If it does not, then check the fan relay and temperature switch, and check for a separated connector or severed wire between the relay and temperature switch.
2. DISCONNECT TEMPERATURE SWITCH WIRE
Confirm that the fan rotates.
If it does not, then check the fan relay, fan motor, ignition relay and fuse, and check for a short circuit between the fan relay and temperature switch.
3. CONNECT TEMPERATURE SWITCH WIRE
High Temperature [above 90°C or 194°F]
4. START ENGINE
(a) Raise the engine temperature to above 90°C (194°F).
(b) Confirm that the fan rotates.
If it doesn't, replace the temperature switch.
INSPECTION OF ELECTRIC COOLING FAN
1. INSPECT TEMPERATURE SWITCH
NOTE: Located at the radiator lower tank.
(a) Using an ohmmeter, check that there is no continuity when the coolant is above 90°C (194°F).
(b) Check that there is continuity when the coolant temperature is below 83°C (181°F).
2. INSPECT IGNITION RELAY
NOTE: Located in the engine compartment relay box.
(a) Using an ohmmeter, measure the resistance between terminals 1 and 2.
Resistance: 50 - 80 Ohms
(b) Connect a 12V battery across terminals 1 and 2. Using an ohmmeter, check that there is continuity between terminals 3 and 4.
Check that there is no continuity between terminals 4 and 5.
If any of the above checks are not as specified, replace the ignition relay.
3. INSPECT FAN MOTOR RELAY
NOTE: Located in the engine compartment relay box.
(a) Using an ohmmeter, measure the resistance between terminals 1 and 2.
Resistance: 50 - 80 Ohms
(b) Connect a 12V battery across terminals 1 and 2.
Using an ohmmeter, check for continuity between terminals 3 and 4.
If any of the above checks are not as specified, replace the fan motor relay.
4. INSPECT FAN MOTOR
(a) Connect the battery and ammeter to the fan motor connector.
(b) Check to see that the motor rotates smoothly, and current is as follows:
Current: 3.1 - 4.3 A