I have 2 fan motors to cool the radiator when it hets hot, neither fan is working and they both stopped wotking at the same time and now my engine over heats when i run the air conditioner or i am stopped in traffic for long periods of time, can you tell me what could cause these fans not to function?

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Radiator fan motor or radiator fan thermostat defective/

Also there is a relay that operates the fan motor

In town not enough air passing through radiator allowing it to over temp.. With heater fan running acts like cooling fan keeping engine cool

Highway driving ample air passing through radiator without fan.

Hill climbing requires cooling fan/

Hope this helps?

You need to have a self test run of the engine cooling fans, this takes dealer level tools to complete. The test runs an active test of the fans which are computer controlled.

FIRST OF ALL I WOULD REPLACE THERMOSTAT AND RADIATOR PRESSURE CAP THEN CHECK SEE IF COOLING FAN RUNNING.WHILE CAR OVERHEATING. IF NOT CHECK COOLING FAN FUSE AND RELAY.IF ALL IS GOOD THE ENGINE COOLANT TEMPERATURE SENSOR COULD BE FAULTY.HOT WIRE SEE COOLANT FAN WORKS IF NOT, COOLING FAN MOTOR BAD NEED REPLACING.IF COOLING FAN MOTOR WORKING PROBLEM COULD BE IN FAN MOTOR WIRING OR PCM FAILED.

Hello: Check the radiator cooling fan. With engine running and A/C on open hood look down on the back-side of the grill, that's where the cooling fan is. It should be running, if not check the fuses, cooling fan relays/module if they are ok then you may have a cooling fan motor failure. You can use jumper cables to hot wire the fan motor to see if it runs.

CHECK TO SEE IF COOLING FAN IS RUNNING.IF NO CHECK COOLING FAN FUSE AND RELAY.THE COOLING FAN NEED TO BE RUNNING WHEN AC ON BECAUSE AIR CONDITIONER PUT A LOAD ON ENGINE.COOLING FAN KEEP RADIATOR AND AC CONDENSOR COOL.FAN NEED TO RUNNING.

Hi,
The problem would be the radiator cooling fan.

• Check first the relay, interchange that relay from similar one in the fuse box in the engine compartment.
• Check the radiator fan motor, pull down the fan motor and directly connect it to the battery.
• Check the cooling fan thermo switch, it is located underneath/side of the radiator assembly. To check it, just get a paper clip and short the socket connector, fan should run if not the relay has a problem or the fan motor is already malfunctioning.

Hope that helps you out.
Tanks for asking FixYa!

Follow the wiring back from the fan motor, the relay is often found at about the height of the bottom of the radiator on the inner fender. Check that connection is clean and free of corrosion. Check that the fan works by taking two trailing wires directly from the bettery terminals and connecting then to the fan motor directly. Use a voltmeter and check the voltage at the relay when engine is cold and shortly after the radiator top hose from the engine becomes hot (the coolant sensor should have signalled for the fan to switch on at this time). No voltage indicates a break in the circuit or faulty sensor. Voltage but no fan indicates faulty relay

sounds like your cooling fans are not working. look under the hood with the a/c on and check if your electric cooling fan s are working. they are mounted to the inside of the radiator.

Sounds like the radiator cooling fan is not operating. LIft the hood and let the car idle. At about the same time the top rubber hose from the engine to the radiator becomes hot the fan should come on. Check the fan fuse, fan motor relay and also the temperature sensor in the engine. Finally check the fan motor has not seized and that the motor still works (put 12volts across it). The car cools when on the move as air pushing through the radiator due the motion has a cooling effect