Updated at: 22-07-2022 - By: Lucas

In the middle of a long drive, have you ever noticed your car’s heating system suddenly come on? There’s a good chance you’ve pondered why your car’s radiator fan keeps cycling on and off. We’ll look into why this is happening and what you can do about it in this article. What are you waiting for? Keep reading to find out more!

Why does the radiator fan turn on and off constantly?

Heat is dissipated via the radiator fan, which regulates the engine’s temperature. In order to maintain a constant operating temperature, the fan should operate in an intermittent, on-and-off fashion.

Radiator fans that come on and go off intermittently can be caused by a variety of issues, including the following:

1. Low coolant levels

Low coolant levels

The fan will switch on if the coolant levels in the radiator fall below a specific threshold. This will help the engine cool down. Temperatures should return to a safe level after using this method.

2. Malfunctioning thermostat

A malfunctioning thermostat will not be able to keep the engine’s temperature in check. In order to cool everything down, the fan will be constantly on and off.

3. Clogged air filters

Clogged air filters

The engine’s air intake will be impeded if the filters become clogged. When the engine overheats, the radiator fan kicks on to cool it down.

4. Broken fan belt

The fan’s rotation will be halted if the fan belt snaps or gets slack. When the engine overheats, the radiator fan kicks on to cool it down.

5. Faulty cooling system

Faulty cooling system

If the cooling system is malfunctioning, the fan may run constantly on and off. A clogged radiator, a broken water pump, or a leak in the system could all be to blame.

If your radiator fan is frequently going on and off, it’s advisable to take it to a mechanic for an inspection. They’ll be able to identify the issue and offer a plan of action that is best for you.

Is the cooling fan switch responsible for a fan that keeps going on and off?

The cooling fan switch controls the fan’s on and off cycles. The engine can overheat and be damaged if a malfunctioning cooling fan switch causes the fan to cycle on and off frequently.

You’ll need to replace your car’s cooling fan switch if it’s not working properly. Fortunately, it’s a simple job that just about everyone can complete.

You will need to remove the hood of your automobile to replace the cooling fan switch. You’ll see the fan assembly when you open the hood. The two wires that connect to the cooling fan switch are visible on the left side of the fan.

Remove the switch from the fan and carefully detach the wires from the switch. If you’re unsure if you can do this task, it’s best to leave it to the professionals.

Once the old switch is gone, follow the same methods you used to remove it to install the new one. Close your car’s bonnet after making sure the wires are correctly connected to the switch. Take a look at the fan to see if it’s working as it should. Check with a mechanic if this doesn’t solve the problem.

Does ECU control the radiator fan?

Yes, the radiator fan is indeed controlled by the ECU. If the ECU has a malfunction, the fan may keep turning on and off. Drivers may find it difficult to pinpoint the source of the issue, which can be extremely upsetting.

It is critical that you have your vehicle inspected by a professional if you are having this problem. The fan may be cycling on and off because of a fault with the ECU or some other component. You may get your car back in working order by recognizing and correcting the problem.

How often should the radiator fan come on?

During a vehicle’s normal operation, the radiator fan should be activated. Engine cooling and passenger comfort are both assisted by the fan.

The engine can overheat if the fan does not turn on, and this might cause catastrophic damage. When the air conditioner is switched on, the fan should also turn on. As a result, the air conditioner is able to operate at peak efficiency.

Can I check if the radiator fan is bad without removing it from the engine?

Even without removing the radiator fan, you can determine if it’s defective. When the fan is running, you can do this by listening to it.

Squealing is an indication that the fan is malfunctioning and needs to be replaced. You can also feel the fan’s airflow for confirmation.

There’s a good chance that the fan has to be changed if the air is too hot. Final check: inspect fan blades for wear and tear. If the fan’s blades are twisted or broken, it’s time to get a new one.

Can a radiator fan that keeps going on and off be caused by a bad thermostat?

A malfunctioning thermostat may be to blame for a constantly running radiator fan. The radiator fan won’t know when to turn on or off if the thermostat isn’t working properly. There is a risk that the fan will keep turning on and off, which can be irritating and unpleasant.

You should have a professional inspect your thermostat to see whether it needs to be replaced if you are having this issue.

You may save money on energy bills by replacing your thermostat, which is a relatively inexpensive project. To determine if your thermostat is malfunctioning, consult a heating and conditioning expert.

Because the engine is attempting to maintain a certain temperature, the radiator fan frequently cycles on and off. The radiator fan is activated to reduce engine temperature when it becomes too hot. The radiator fan is activated when the engine temperature drops below a certain level.