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Car AC Turns On And Off Randomly – What’s Going On?

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Nothing is more frustrating than your AC not working correctly on a hot day. However, what could be wrong if it keeps turning on and off? We have listed the possible culprits to this problem below.

If your AC turns on and off randomly, it could be due to the following issues:

  • Clogged Air Filter
  • Lack of Freon
  • Too Much Freon in Line
  • Bad Compressor
  • Faulty Air Control Valve
  • Bad Condensor
  • Fan Cycling Switch Malfunction
  • Blown Fuse
  • Bad Relay
  • Faulty Blower Motor
  • Blocked Air Intake
  • Bad Electric Controlled Body
  • Damaged Belt or Hoses
  • Refrigerant Leak
  • Broken Cooling Fans

As you can see, there are several reasons your AC is turning on and off at random. First, however, we will discuss the functions of each of these parts and why they would cause issues with your car's air conditioning. In addition, we will answer other frequently asked questions about car issues, so read on!

Three knobs indicator air conditioning air flow and heater, Car AC Turns On And Off Randomly - What's Going On?

Car AC Turns On And Off Randomly - What's Going On?

If you have ever been in a hot car, you know how important air conditioning is. However, in the heat of the summer, your car's air conditioning system may not be working correctly. If this is happening to you, a few things could be going on with your AC unit.

For your AC to turn off and on at random, there could be several reasons why it's occurring. Let's take a look at them below:

A car technician checking the liquid coolant level of the car

Clogged Air Filter

Technician changing the air filter for the car AC

The air filter is the first thing to check when your car's AC keeps turning on and off. If it is covered in dirt or other debris, this could be causing the condenser coils not to get enough airflow.

Lack of Freon

Car mechanic recharging the car freon

If your AC stops working in the middle of summer, it could be due to a lack of refrigerant. You will need to recharge the system to get the air conditioning back up and running when this happens.

Too Much Freon in Line

Having too much freon in line is another reason why your car might keep turning on and off. If there is too much of this coolant, it can cause the AC to be turned on all the time or not turned on at all. This could be very frustrating for you to deal with if your AC keeps turning off and on.

Bad Compressor

If you have a faulty compressor in your car's AC system, then it can be turned on and off at random. This is because it will cycle through trying to get enough power to turn on or not getting any power at all if it's faulty.

Faulty Air Control Valve

The air control valve controls how much air is going into your AC. So if your AC is turning on and off, then this could be the reason as to why. 

Bad Condensor

A bad condenser can also cause the AC to turn on and off randomly. If the condenser isn't working correctly, it won't provide enough cooling power for your system.

Fan Cycling Switch Malfunction

If you have a fan cycling switch malfunction, this will keep causing your AC to turn on and off repeatedly. If this is happening, then your switch may need to be replaced so you can have your AC up and running again.

Blown Fuse

If your AC keeps turning on and off and it's not due to anything else, then you may have a blown fuse. If this is happening, then check the fuses for your system to see if one of them has been blown. You can check your owner's manual to find the fuse that controls your vehicle's AC. 

Bad Relay

A relay that isn't working properly can cause your AC to turn on and off randomly. This is because if the relay isn't working, it may not send enough power to your system's compressor.

Faulty Blower Motor

Car blower motor replacement

If you have a faulty blower motor, this is another reason your car's AC is turning on and off. When the motor isn't working correctly, it can cause your air conditioning system to turn on and off at random, so check it out for yourself!

Blocked Air Intake

A blocked air intake could also be causing your car AC to turn on and off at random. If it is blocked, then your condenser coils will not be getting enough airflow, so they won't have the power to run. It could also cause other problems with your car's air conditioning system as well.

Bad Electric Controlled Body Module

If your car's electric controlled body module isn't working then, this could keep causing the AC to turn on and off at random. If this happens, you may need to have it replaced with a new one so that your air conditioning system works properly again.

Damaged Belt or Hoses

If your car's AC has a damaged belt or hose, then this will cause it to turn on and off at random. This is because the belt, in particular, powers the compressor, so when it breaks down, you'll have issues with your air conditioning system not working right.

Refrigerant Leak

A refrigerant leak will be causing your AC to turn on and off at random. If there is a refrigerant leak, it means that the freon is leaking out of the system, so you'll need to get the problem taken care of as soon as possible!

Broken Cooling Fans

If you have a broken cooling fan, then this will cause your car AC to turn on and off randomly. If the fan isn't working correctly, it won't provide enough airflow into your air conditioning system.

How often should a car AC compressor cycle on and off?

If your AC compressor is working correctly, it should cycle 2-3 times an hour. This helps provide proper cooling inside the cabin of the vehicle.

However, if it is cycling too often or not enough, that could signify that you have a faulty part. If this is happening, you may need to have it checked out by a professional to determine the problem!

Should a car AC fan run all time?

Every time your AC is turned on, the fan will run. Sometimes, if your vehicle is overly hot, the fan will have to work overtime to keep up with the temperatures.

If the AC fan turns on and off, this could be a sign of a problem. If it has been doing this for an extended time, you may need to have your AC checked out by a professional as soon as possible because it may require repair.

A car air conditioning turned on a white neon light indicator

How much does it cost to fix a car AC?

If it is a small problem, you may be able to get it fixed yourself. However, the cost of your car AC repair will vary depending on what needs to be done and whether or not you have a warranty for the part that needs to be replaced!

If you have to have a mechanic repair the issue, the average cost is $2,500. However, it is essential to know that this price can be significantly less if it is a simple part to fix.

How do you repair a car AC?

If your car AC is only making noise and not blowing cold air, then it may just need to be serviced. One thing that you can do is to check your onboard manual for any directions on how to do this.

If it needs a part replaced, you will need to take the vehicle into the shop and have the mechanic diagnose and repair it. It's important to know that it can be costly depending on what is wrong with your AC!

How long does car AC last?

The life of your car AC will vary from vehicle to vehicle. Therefore, it is important to have a mechanic look at the vehicle's history and ask a previous owner to estimate how old it is.

On average, the lifespan is 8-10 years, depending on where you live and whether or not you have it serviced regularly. In addition, your car's AC may need a recharge which you can do once a year if need be.

A car technician checking the liquid coolant level of the car

Can you drive with an AC compressor failure?

If your car is not running hot, you can get by driving around without air conditioning. The risk you take is if the AC compressor ends up causing damage to the belt. If this happens, then you could be looking at hefty repair costs.

Final Thoughts

Three knobs indicator air conditioning air flow and heater

A car AC compressor turning on and off at random can be a red flag that something is not working correctly. If you notice this, then it may require repair soon.

If the issue isn't so urgent, you can have someone look at your vehicle or refer to your vehicle manual for how to do it.

For more articles like this one, then you should check out:

Car Shakes When Turning And Accelerating—What Could Be Wrong?

Rattling Noise In Car When Accelerating—What Could Be Wrong?

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