Cooling Fan Replacement – Sydney Car Repair

What is a cooling fan?

A cooling fan is a supporting component in your car’s cooling system.

The fan draws air through the radiator when the fan is engaged, drawing heat out of the hot coolant circulating through the radiator.

Older models may have a mechanical cooling fan driven by the drive belt while most modern cars have an electric cooling fan mounted on the radiator.

Some cars even have dual electric cooling fans to increase the fan’s function.

The fan itself has plastic blades and it’s attached to a drive system.

The older mechanical system is a clutch-style hub attached to a drive pulley, and it engages when the temperature starts to climb.

The modern electric cooling fan is driven by an electric motor that starts up when a temperature sensor indicates it should do so.

When the cooling fan has damaged blades or it does not engage when the engine is hot, it will require replacement.

Symptoms you require cooling fan replacement

• The engine temperature exceeds normal operating temperature or your engine overheats
• The cooling fan blades are cracked or broken
• The cooling fan won’t engage when at operating temperature
• The fuse for the cooling fan blows repeatedly

Can I drive a car if the radiator fan is not working?

No, it is not recommended to drive without the radiator fan working. This can cause the engine to overheat which can lead to permanent and expensive engine damage.

What happens if the radiator fan is not working?

If the radiator fan is not working, your car can overheat when the car is idling or driving at lower speeds. At higher speeds, the cooling system will still be cooled by the wind. However, an overheated engine can cause serious damage to your engine, so you don’t want to take the risk.

How To Fix A Radiator Fan Not Coming On

To fix a radiator fan that won’t start, you should begin by checking the fuses. You also want to make sure the coolant level is good. Then you need to read the error codes with a scanner and measure the wires with a mustimeter.

Here is more detailed information on how to fix a radiator fan that won’t start:

1. Check Fuses

The first thing you want to do when your radiator fan is not spinning is to check the fuses. There will be a large fuse for the fan itself that you want to check. It will be between 30 and 50 amps, and it is usually a larger fuse located in the engine compartment. But to find the exact location of your car model, you need to check your owner’s manual.

There will also be one or more smaller fuses for the radiator fan control module or relay in most car models. To find these fuses, you must again check the instruction manual for the location. These fuses can also be located inside the car.

If you find a blown fuse, you may want to inspect the wiring and try to figure out why the fuse blew. However, sometimes a blown fuse may just be a temporary problem.

2. Check Coolant Level

The next step you want to do is to check the coolant level. If the coolant is low, it can cause many different problems with the radiator fan.

Checking the coolant level is easy, just open the hood and locate the coolant reservoir. You will see a max sign on the reservoir and sometimes a min sign as well. Make sure the engine is cold and open the container carefully. Fill the container with antifreeze up to the maximum mark.

3. Unplug Coolant Temperature Sensor

Another way to determine if the coolant temperature sensor is to disconnect the sensor. In most car models, the radiator fan should start when the coolant temp sensor is disconnected, and the car is running.

But for this, you need to find out which of the coolant temperature sensors controls the radiator fan, as there may be a separate one for the engine control module and the radiator fan control. Also, disconnecting the engine control module coolant temperature sensor may result in a check engine light on your dash.

4. Check Trouble Codes

Modern cars use very high technology and almost always when there is a problem you want to read the trouble codes from the control modules before doing anything else.

This is also a good idea if your radiator fan is not working. This is because in many car models the radiator fan is controlled by the engine control module, and if your fan is not working you want to check if the ECM knows what the problem is.

For example, if the engine control module stores a trouble code on the coolant temperature sensor, it can also cause the radiator fan to malfunction. To read the fault codes, you need to use an OBD2 scanner. You can either buy one to use at home or go to an auto repair shop so they can read the codes for you.

5. Measure wirings

If you’ve tried all the things above but still can’t figure out what’s causing the radiator fan to not start, it’s time to start with some more advanced diagnostics. To find out what is wrong now you need to use a multimeter and measure the wires. This can be quite difficult if you have no knowledge of vehicle diagnostics, and you may want to skip to the next step.

Using a multimeter, you must first measure the power and ground wire coming to the radiator fan. If you have both power and ground to the fan when it starts, you need to replace the radiator fan. If you are getting no power, you need to move on to diagnosing the fan relay and find out why it won’t activate.

You can then try to bridge the radiator fan relay, and if the radiator fan starts when you do that, you know there is a problem with the relay control, like a bad coolant temperature sensor for example.

6. Talk to a professional

Fixing car problems on modern car models can be quite difficult due to all the electronics and sometimes it can be good to have a professional take a look at the car instead. Many professional mechanics have thousands of hours of training in automotive diagnostics and can quickly find problems like this.

Therefore, it doesn’t necessarily have to be more expensive to get the help of a mechanic instead of making a bad diagnosis and replacing the wrong parts all the time.