Exception in rendering!

Message: window is not defined

ReferenceError: window is not defined
    at new c (/tmp/execjs20161209-3562-w6cqxbjs:136:3912)
    at m.mountComponent (/tmp/execjs20161209-3562-w6cqxbjs:47:15602)
    at /tmp/execjs20161209-3562-w6cqxbjs:49:31860
    at a.r.perform (/tmp/execjs20161209-3562-w6cqxbjs:47:12503)
    at Object.a [as renderToString] (/tmp/execjs20161209-3562-w6cqxbjs:49:31821)
    at r (/tmp/execjs20161209-3562-w6cqxbjs:50:21164)
    at Object.S.ReactOnRails.serverRenderReactComponent (/tmp/execjs20161209-3562-w6cqxbjs:32:6073)
    at eval (eval at <anonymous> (/tmp/execjs20161209-3562-w6cqxbjs:173:8), <anonymous>:10:23)
    at eval (eval at <anonymous> (/tmp/execjs20161209-3562-w6cqxbjs:173:8), <anonymous>:17:3)
    at /tmp/execjs20161209-3562-w6cqxbjs:173:8

Symptoms of a Bad or Failing Cooling Fan Resistor

Cooling fan resistor

Virtually all modern vehicles built today use electric cooling fans to help pull air through the radiator to keep the engine cool. Once the coolant temperature sensor detects that the engine temperature has exceeded acceptable levels, the cooling fans will be activated to keep the engine cool. Many vehicles come equipped with cooling fans that operate on more than one speed setting. This is made possible by routing their power through the cooling fan resistor. The cooling fan resistor is an electrical resistor that limits power to the fan in steps, so that the fan can operate at different speeds according to the cooling system’s demands. Since power to the cooling fan is sometimes routed through the cooling fan resistor, when it fails or has any problems, it can cause issues with the regular operation of the fans, which can lead to overheating. Usually a bad cooling fan resistor will produce a few symptoms that can alert the driver of a potential problem that should be serviced.

1. Engine overheats

One of the first symptoms of a potential problem with the cooling fan resistor is engine overheating. If the cooling fan resistor fails or has any issues, it can cause power to be cut off from the cooling fans, which can lead to overheating. Any sort of overheating issue should be tended to as soon as possible to avoid the possible engine damage.

2. Cooling fan speed issues

Another symptom of a possible problem with the cooling fan resistor is issues with the cooling fan speed. If the resistor breaks or has any issues it may cause the fans to only function on certain settings. The cooling fan resistor is meant to send power to the fans in steps, so that the fans may operate at different speeds. If any of the individual steps or switches fail, it will disable the cooling fans from operating on that speed setting. You may notice that the cooling fans only operate at one speed, when they used to operate on two or more.

3. Cooling fans never turn off

Another symptom of a potential problem with the cooling fan resistor is cooling fans that stay on at all times. If the resistor shorts or fails, it can cause the cooling fans to stay on even when they are not supposed to. In certain cases, the cooling fans may even stay on when the vehicle is turned off, and will create a large parasitic drain that will eventually kill the battery.

The cooling fan resistor is an important component, as it is one of the components that routes power for the cooling fans. For this reason, if you suspect that your cooling fan resistor may be having an issue, have the vehicle inspected by a professional technician, such as one from YourMechanic, to determine if your car needs a cooling fan resistor replacement.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

Post a question and get free advice from our certified mechanics.

ASK A QUESTION

More related articles

How to Transfer a Car Title in Idaho
In order to prove ownership of a car, you must have the title. However, when a car is sold, given away or inherited, the title needs...
Veteran and Military Driver Laws and Benefits in New Mexico
The state of New Mexico offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch...
P2159 OBD-II Trouble Code: Vehicle Speed Sensor B Range/Performance
Diagnostic Trouble Code (DTC): P2159 P2159 code definition Vehicle Speed Sensor B Range/Performance Related Trouble Codes: P2158: Vehicle Speed Sensor B P2160: Vehicle Speed Sensor B Circuit Low P2161:...


Related questions

Q: AC fan only works on high

This is a common problem when the A/C blower motor resistor goes out. This is an inexpensive part to replace and is found under the dash near the A/C blower motor. This resistor controls the speed of the blower fan....

Q: No air coming from vents

Try to put the blower on high speed and move the mode to floor or windshield to see if any air is felt or the noise from the motor is heard. If you hear the blower running but still get...

Q: Car overheated while idling. What is wrong

There are a few faults that will cause your 2013 Hyundai Elantra to overheat when idling. The most common would be the electric fans not functioning. When air is flowing over the radiator the car works fine, but when the...