The radiator fan may run up to five minutes and sometimes longer. Unless there is an electrical issue, it may stay on all the time until it drains the battery. When the engine is running, the coolant circulates and flows to the radiator, where heat is dissipated.

How long should a radiator fan run?

But, on a normal 70–80 degree day you should hear the fan run, I would guess, after about 15 to 20 minutes of idling from a cold start. When the electric cooling fan operates is purely a function of the setting of the temperature switch used to control power to the fan.

How often should radiator fan come on?

Most fans should come on when the coolant reaches about 200 to 230 degrees. If the fan does not come on, something in the control circuit is defective.

Is it normal for radiator fan to stay on?

It means you have an electric radiator cooling fan and it probably means the manufacturer designed the system so the fan stays on for a while after the engine stops to dissipate the heat that has soaked into the engine and engine bay. Perfectly normal. Unless it never switches off, then you have a problem.

Do radiator fans turn off?

Starting from the top, electric radiator fans often do turn off when the car reaches highway speed, simply because the forced air flow through the radiator keeps the engine coolant temperature low enough they aren’t needed.

When should my car fan turn on?

Your radiator fan should kick in at about 200 degrees Fahrenheit. If you notice your vehicle is overheating or at the very least running hotter than it normally does, listen for the fan to see if you can hear it.

How long does a radiator fan take to turn on?

Wait 15-20 minutes for the fan to come on after the control valve has been closed.

Why is my car fan not turning off?

Pull the cooling fan relay out of the box. Replace the cooling fan relay with a new one. A stuck closed relay is the only thing that can operate the cooling fan continuously with the key off. The computer looses power with the key off and the same applies to the coolant temperature sensor.

Why is my car fan still running when car is off?

It’s normal for some vehicles to have a fan run for a few minutes after the car is shut off, generally to keep the engine cool. However, if the fan is running for an extended period, the fan itself can become damaged due to overuse. … It’s possible you may have a module or relay failing in your car.

Why does my car radiator fan keep running?

The reason behind this is quite simple . After turning the engine off, the ECU unit tells the fan to continue running as the coolant is still hot. Until the temperature comes down to normal, it keeps running which makes a bit of sound. DONT WORRY ITS NORMAL.

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How can I tell if my radiator fan is working?

A simple way to check if the radiator fan is working is to start your engine and turn the air-conditioning system (A/C) to the maximum speed. If the fan is spinning, then it means that the fan motor, fuse, wiring, and relay are all working properly.

How do I know if my radiator fan is not working?

The radiator fans have electrical motors inside of them, which will wear out after some years. You can test the electrical radiator fans by taking a wire from the car battery, unplug the radiator fan connector, and put 12v+ and ground into the connector. This is the fastest and easiest way to test your radiator fans.

Can a car run on one fan?

Yes, of course. But, the engine might get a little hot, and it isn’t a good idea to continue to do so without getting the other fan (or two) repaired or replaced… If there is more than one fan, there is a reason for it.

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

As such, you should never drive your vehicle if the cooling fan isn’t working even though you can. … If the radiator does not have cool air blowing on it constantly, it will overheat eventually, so you’d need the perfect combination of weather and traffic to drive effectively without a radiator fan.

Should radiator fan turn on when AC is off?

The AC controls may operate the fan from a place in the control circuit after the normal temp sensor so everything is OK when the AC is on. Also the Fan may be on continuously when the AC is operating.

Can I drive my car with a bad radiator fan?

Yes, if your radiator cooling fan fails, you can drive with it. Technically, your vehicle engine does not need a radiator fan to operate. However, if your vehicle engine does not receive enough air blowing it constantly, it will eventually lead to overheating.

Should both my radiator fans turn on?

Both fans should come on when the A/C is on. If one or both fans fail to come on, the lack of additional cooling provided by the fan may cause poor A/C cooling performance, and it may cause the A/C compressor to overheat and fail.

Does radiator fan turn on in winter?

To answer the question, yes, most likely you will be fine without a fan running. However you might overheat if stuck at traffic or idle for a while. That’s a good observation. The fans may have been operational all the time but not spinning during the OP’s tests of the new A/C.

How much does it cost to fix a radiator fan?

As one of the more expensive car repairs needed (not including the replacement of a seized car engine, obviously), the replacement of the radiator coolant fan could incur about $128 to $162 in labor costs and around $465 in parts. So, total radiator fan replacement cost could be anywhere from $592 to $627.

Why does my car sound like it's running when I turn it off?

Engine cooling fans and other systems are programmed to keep running in some cars even when the engine is off. … Once outside the car, she could hear a fan running in the engine area and asked us if this is normal. It is. And many other sounds from under the hood of a car that has been shut off are also normal.

Why does my radiator fan keep turning on and off?

vehicles with electronic cooling fans turn on and off to help regulate the engine temperature. if the regulator senses that is getting too hot it kicks the fan on to cool the radiator down. when it is cooled down enough it kicks off and allows the engine to heat back up.

How do I know if my cooling fan relay is bad?

1. The engine runs hot or overheats. …
2. The cooling fans don’t work. …
3. The cooling fans keep running. …
4. Warning lights. …
5. Poor air conditioning performance. …
6. Swapping Relays. …
7. Measuring the Relay Coil’s Resistance. …
8. Listening for Noises.

How many radiator fans does a car have?

A lot of drivers’ vehicles will actually have two radiator fans. One, both or neither may be running at any given time depending on the conditions. When you are cruising at highway speeds, the air rushing over the radiator and around the engine will help control the heat.

Why does radiator have two fans?

One fan is controlled by a coolant temperature sensor, and the second (only installed if the car has air conditioning) is only turned on if the first fan isn’t able to provide enough cooling (air conditioner running, or coolant temperature rises a set amount above switch point for first fan).

Is radiator fan important?

The radiator fan has an important job in the engine compartment. It can push air through the radiator core or pull it through. It must cool the antifreeze that circulates through the block and head passages and reduces the engine temperature.