AC Compressor Shuts off at High RPM- Easy Fixing

AC Compressor Shuts off at High RPM
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AC is a very important thing in the summer. The AC compressor sometimes shows a problem in that it stops working when the engine works at a high RPM (Revolutions per minute). It is really a very common issue.

Sometimes, the AC works properly from the start but suddenly shuts off. It can show the symptom right after reaching a specific RPM. It can be a continuous problem or often it starts working after a few minutes of getting down the RPM.

You do not have to worry about the problem at the initial stage. This is advisable to fix the problem as soon as possible. When the problem will stay for a long time, it can do severe damage to your vehicle. 

Stopping AC at a high RPM does not prevent your vehicle from working properly but if you do not troubleshoot the problem, it may cause big internal damage to your vehicle. This article shows the causes of shutting off the AC compressor at high RPM and the best ways to fix the problem. 

      Causes of shutting off the AC compressor at high RPM

AC Compressor Shuts off at High RPM

1. Coolant leaks onto the belts

If you are looking for the reason for shutting off your AC compressor at high RPM, it can be a leakage of your coolant. The water pump also runs faster when the engine runs at high RPM. If there is a leak onto the belts, the water turns out.

Then the belt of the compressor pulley slips from the actual place. That is why the refrigerant pressure becomes lower than expected. Thus, the IHKA (Integrated Automatic Heating and Air) sensor stops the compressor from working. That is why the AC turns off at high RPM. 

2. Faulty AUX fan

AUX fan means an auxiliary fan. There are two fans that work for the whole air conditioning system. One works for the air conditioning condenser and another one works for the radiator. After working for a while, the radiator starts to start hot.

If the auxiliary fan is working properly, the radiator can release the heat. However, if somehow the auxiliary fan stops working then the radiator also stops working when it becomes hotter than expected. That is why the AC compressor also stops working at high RPM. 

3. High pressure cut off switch

There is a high-pressure cut-off switch. The switch works as a sensor. If the temperature of the compressor becomes very hot that the sensor takes it as a danger, then the high-pressure cut-off switch separates the AC compressor from the power supply. As there is no power supply, the AC compressor turns off. Usually, the temperature of the compressor becomes higher when the engine is at high RPM.

4. Low suction pressure

Sometimes, you can find a low suction problem. When the engine runs at high RPM, the suction pressure decreases. That causes many problems for your compressor. Because of the low suction problem, the oil can turn out of your compressor, and also air and moisture can get into it. That can damage your compressor permanently. That can also be the reason for shutting off your compressor. 

5. Electrical problem

There are so many electrical connections in a car. If you have got a loose connection among them, your AC compressor can stop working. Usually, it happens when the wire is not connected properly. The wire of the AC compressor gets disconnected. That is why the compressor shuts off. 

Steps on How to Fix The Problem of Shutting Off the AC Compressor at High RPM

How to Fix The Problem of Shutting Off the AC Compressor at High RPM

i. Repair or replace the coolant leaks

If you see any red or green fluid in the engine compartment, it might happen because of the coolant leaks. To fix the problem, you have to open the radiator cap. You should do this after making sure that the engine is cold.

Then you have to disconnect the battery. Then remove the engine cover. After that, you have to remove the splash shield of the radiator drain. Then you have to remove the cross vehicle brace. After that, remove the coolant expansion reservoir. Then pull the hose out of the retainer and slide the reservoir straight up.

Then disconnect the hose from the reservoir. Then put the engine cap back in its place. Then you have to remove the belt. If you have removed the belt, then check the belt and make sure if there are any cracks or not. You have to remove the alternator next. Removing the alternator, you can see the elbows. You have to change the elbows. Click here to buy new elbows.

Make sure you clean the whole area before changing the elbows. If you find your car’s elbow in an irreparable condition, change the elbow. Otherwise, you can repair it. Hopefully, you will get your problem fixed. Then assemble all the things to the right position. You will have needed some wrenches to pull things up or tight them. You can check out these wrench sets and ratchets

ii. Replace the AUX fan

If you have followed the upper steps and can face the same problem yet or you do not have the first problem, then follow this step. You should check if your auxiliary fan is not working properly or not. If you find a faulty auxiliary fan, you have to change the fan with a new one. It might solve your problem. There are so many AUX fans available in the market. Here is a standard sample of the Best auxiliary fan.

iii. Reconnecting the high pressure cut off switch

You have to check your high-pressure cut-off switch to find out the reason because sometimes the compressor becomes excessively hot. Then the switch separates the power supply for safety purposes. Therefore, you will need a new switch and reconnect the power supply and the compressor. Click here to buy a new high-pressure cut-off switch. 

iv. Set the indoor temperature to high

In most cases, the low suction problem happens because of the low temperature in the compressor. If you set the temperature too high, you can find the problem solved. You can also clean the filter. Sometimes, this is also a reason for the problem. 

v. Checking the electrical connections

If you still have the problem, then you have to check your wire connections. You can check all the wire connections which are related to AC. You have to connect the wires properly. Hopefully, you will have your problem fixed. 


There are many reasons that can cause the AC compressor to shut off. One of the reasons or more can be working for the problem at a time. Fortunately, this article has mentioned all the reasons for this problem and the best ways to troubleshoot it. If you follow them, you will be able to solve the problem very easily. 

If you have already experienced the problem, do not be late to take any necessary steps. You can try on your own to fix the problem before going to any mechanic. That will save you a lot of money and you can learn many things from this problem. If you face the same problem in the future, you can solve it easily without anyone’s help. Lastly, it is advisable to fix this AC compressor problem as early as possible.

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