Why does my car overheat when the air conditioning is on? (Resolved) (2023)

When the summer heat is above average, all you have to do is turn on the air conditioning and enjoy the cool breeze in your car. Unfortunately, this is not always the case.

Sometimes you turn on the AC and the car overheats.

If you've ever found yourself in this situation, you know how frustrating it can be. In this article we will discuss some of the main reasons why your car overheats when you turn on the air conditioner. We will also tell you a solution for each case.


Why does my car overheat when the air conditioning is on?

There can be several reasons why your car overheats when the air conditioning (AC) is on. The air conditioning system may be low on refrigerant, the air conditioning compressor may be defective, or the radiator may be blocked. It is recommended that a mechanic diagnose and fix the problem to prevent further damage to your vehicle.

Components of a car cooling system

A car's cooling system consists of several components. See how the components make the cooling system work.


A cooling fan's role is to slow down or speed up based on engine temperature. It keeps the engine cool and doesn't allow it to overheat quickly.

water pump

Another component is the water pump, the engine of the car. The function of a pump is to supply water to the cooling system. Does not affect engine oil.


Next comes the radiator, which helps remove residual heat from the engine.


The final component is a thermostat that works efficiently to maintain engine temperature.

What Are the Symptoms of a Bad Air Conditioning Compressor?

Overheating of the car with the air conditioning on is a common problem. But how do you know you have a faulty air conditioner? The signs mentioned below can help you to recognize this.

The interior of the vehicle is hot.

If you notice your car's internal components getting hot, it could be a sign that your car has a faulty AC compressor. When the internal component heats up, a burning smell comes out of the car or air conditioner.

Car temperature gauge

Another sign indicates a car overheating problem when the air conditioner is on. You can read the car's temperature gauge to know the overheating condition.

The car temperature gauge shows you the temperature of the engine coolant. The average temperature should be between 195 degrees and 220 degrees. If the car's temperature gauge shows more than 220 degrees, it means the vehicle is overheating.

The car engine is off

If the car overheats, it will automatically shut down regardless of the cause. You can try turning on the car's air conditioning. If the engine suddenly stalls, this indicates a faulty AC system.

Cloud of steam comes out from under the hood

It is the traditional way of understanding whether there is a problem with the car's air conditioning or not. Apparently, if you see a cloud of steam under the hood, the car is overheating.

Why does my car overheat when the air conditioning is on?

1. Worn out AC compressor

Why does my car overheat when the air conditioning is on? (Resolved) (1)

This is one of the main reasons why your air conditioner overheats. This is especially true if theCar only overheats when A/C is onand temperatures drop when the air conditioning is off.

If this is the problem you are having, then the AC system is faulty and thatThe air conditioning compressor is the main reasonfor this change.

The AC compressor is connected to the engine via the V-belt. When the engine starts, the belt will start to rotate. Supplies power to an AC compressor.

An air conditioning compressor with a worn and bent pulley or a defective bearing puts additional strain on your car's engine. This makes it run longer when the air conditioning is on.

The overloaded motor starts to overheat. And that's what causes the excess heat you feel in the car when the air conditioning is on.

In the case of a damaged air conditioning compressor, the overheating comes from an overloaded car engine.


If you notice this type of heating, quickly turn off the air conditioner. Otherwise the engine may start to melt and break from the inside. When you turn off the air conditioner, the car engine runs normally.

If the compressor is the problem, buy a new compressor. Replace broken parts to get the best performance out of your car.

The following are the best compressors you will find on the market. But the one that fits your car's air conditioning system.

ACDelco 15-20941 GM Genuine A/C Compressor and Clutch Pack

  • Perfect for all General Motors vehicles.
  • Factory original part
  • Reliable, durable and high quality.

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Air conditioning compressor UAC CO 29002C

  • Replacement of the original equipment
  • Add your car model to Amazon to check fitment
  • perfect performance

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2. Sucio, or addictive soda

Why does my car overheat when the air conditioning is on? (Resolved) (2)

The coolant can last a long time without needing to be replaced, but it will eventually need to be changed. When the coolant gets old or dirty, it no longer cools the car like it should.

This means that if the coolant is not working well, your car's engine will start to overheat.

The problem gets worse when the car's air conditioning is turned on. AC requires some extra power from the motor. This means that the engine generates a little more heat.

This is why you will find that when the air conditioning is on, your car will start to heat up. low coolant levelIt can affect the air conditioning system because the air conditioning system depends on the engine's cooling system to function properly.


The solution to this particular problem is simple. Replace coolant. Buy a coolant that will give your car high performance.

This is the only way to solve this problem.

Another reason you need to replace your coolant is to protect other components in your car's engine from corrosion and rust.

BMW 82141467704 Coolant/Antifreeze is the best coolant you can find on the market. If you want to achieve better cooling effect, please release and replace your current coolant. Click hereto try the soda and buy now on Amazon.

3. Defective fans

Why does my car overheat when the air conditioning is on? (Resolved) (3)

And youcar overheatsIf it is idling after turning on the A/C, the fans could be the culprit.

A car's cooling system has a radiator, a fin system located behind the car's grille. The function of the radiator is to remove excess heat from the car and dissipate it through the fins. This is how you keep the engine cool.

When the vehicle is stationary, the fans must be running to ensure adequate cold air circulation in the system. So when the car stops and the fans don't work, you'll feel excessive heat.


If this is the case, you may need a new fan, fan motors, or electrical connectors for the affected fans.

So if you notice your car overheating when the air conditioner is on and the car is stationary, check the fans. This is most likely the problem you are dealing with.

Why does my car overheat when the air conditioning is on? (Resolved) (4)

4. Damaged or blocked radiator

If your fans are working fine but the car is still overheating while idling, so be itthe cooler could be the problem.

In most cases you will find that the radiator is clogged. This happens when your car has sucked in a piece of cardboard, plastic bag or other object that could block the grille, this is blocking airflow. Then not enough air flows through the radiator.

In this case, the car overheats even with the air conditioner on.

Why does my car overheat when the air conditioning is on? (Resolved) (5)


To fix this problem, first check the grid. Check if something is blocking the airflow.

Sometimes you will find that the radiator is damaged, old or dirty. As a result, it does not exchange heat properly.

Corrosion also builds up on the internal fins over time, slowing coolant flow. This reduces the cooling capacity.

In short, to solve this problem you will have to check if the radiator is not damaged or blocked.

Also read:How to Drain an Overloaded Air Conditioner: Steps That Work

Also, some more reasons cause the car to overheat when the air conditioner is on.

Compressor overload

Does your car have a multifunction compressor? If this is the case, it can put a lot of strain on the car's engine load. The problem is that the all-in-one needs a lot of engine power.

The compressor normally cannot handle this pressure. The AC compressor can still adequately load the motor. As a result, the compressor burns out, which overheats the car engine.

Inadequate cooling system

Car overheating with air conditioning on can also be caused by an inadequate cooling system. The main function of a cooling system is to keep the AC condenser cool when the air conditioner is running.

The usual scenario is when you turn on the air conditioner, the air conditioner cooling system reduces the heat. However, if the cooling system fails, the car will overheat.

Adefective water pump, defective condenser fan and clogged condenser fan can cause malfunction of the cooling system.

Defective vehicle components

Did you know that defective vehicle components can cause the car to overheat even when the air conditioning is on? Defective components such as the refrigerator, evaporator, compressor and condenser can put pressure on the air conditioning system. This in turn increases the temperature of the car.

If you want to reduce the chances of your car overheating from faulty components, you should inspect the components regularly. If the components are working efficiently, then everything is fine. But if you find something even smaller, work it out; Otherwise, the car would overheat with the air conditioning running.

Other solutions for car overheating with air conditioning on

Besides trying the mentioned solutions, you can also try these solutions to fix the car overheating issue with the air conditioner on.

Flush cooling system

When a car overheats, it is best to clean the cooling system. You can monitor the cooling system regularly to make sure you're not overheating the car when the air conditioning is on.

Check coolant

Without a doubt, the coolant is an essential part of the vehicle. It is therefore your responsibility to check the coolant regularly. Regular checks and maintenance ensure that the car does not overheat when the air conditioning is on.

If you think there is a problem with the coolant, instead of avoiding the problem, take the vehicle to a mechanic immediately.

check the condenser

The condenser present in the air conditioner is actually a radiator placed between the radiator of the engine and the grille of the car. If you find problems after checking the condenser, you should clean it immediately. Defective capacitors will not function properly, causing the motor to overheat when the AC power is on.

Put water in the cooler

Did you know that you can keep your radiator in good condition by adding water regularly? When the radiator is dry, you need to add water to keep it from fading.

After water is added to the radiator, the car's water pump picks it up and pumps it back through the engine to the radiator.

What to do if your car overheats while driving with the air conditioning on?

At certain times, the car can overheat in traffic with the air conditioning switched on. But what can you do?

Being stuck in traffic is annoying, and if the car overheats with the air conditioning on, it gets worse. But don't worry, because we know what you can do if your air-conditioned car overheats on the road.

Stop your vehicle

First of all, you should stop as soon as you notice a car overheating. However, in certain cases and in certain places it is not possible to stop the vehicle.

Turn off the air conditioning in the car.

If you can't stop, you can turn off the car's air conditioning immediately. You can also turn off the air conditioning after stopping the vehicle. This helps the engine cool down a bit.

Turning off the car air conditioner works best when the car is parked in a safer place and neutralized.

Open the hood of your car

The best thing you can do to prevent your car from overheating when the air conditioning is on is to open the hood. But if the hood is also very hot, avoid touching it. Let the good cool. You can then open the hood and let the steam out.

turn off the engine

Another way to cool down your vehicle on the road is to switch off the engine. But you have to leave the key in the ignition. This keeps the fan running and eventually dissipates the heat.

But if the fan isn't working, it's probably because the main culprit for heating is the fan itself. In this situation, it is advisable to take the vehicle to a mechanic.

Wait about 30 minutes

The estimated time it takes for your vehicle to cool down is 30 minutes. Once your car has cooled down, you can start inspecting for signs of leaks. If you cannot find the problem, contact a professional mechanic to solve the problem before it escalates.

frequently asked questions

Can an air conditioner overheat the car?

The short answer is yes. In most cases this is because the AC compressor draws power from the motor shaft. This puts pressure on the engine. Remember that more heat is wasted when more power is generated in the engine.

Since the cooling component is still not powerful enough to dissipate the excess heat, the car overheats.

Why does the temperature gauge go up when the air conditioner is on?

You should know that the engine overheats even when the air conditioning is on. But there's more to notice than just the rising temperature gauge. This is because the temperature gauge will even go up at certain times due to a malfunction in the coolant temperature sensor.

Why does the car overheat at idle with the air conditioning on?

With the air conditioner on, the car overheats not only during operation, but also when idling. Usually it happens because of defective fan. If the fan fails, the heat transfer between the hot coolant and the outside air no longer improves.

Therefore, if the fan fails at idle, air will not flow through the radiator and condenser fins. Therefore the car overheats.

Can I drive my car with a defective air conditioning compressor?

You can drive your car with a faulty air conditioning compressor as long as you don't need to bring cold air into the car. However, it is recommended to fix the problem quickly instead of ignoring it.


If your car overheats when the air conditioner is on, there is likely a problem with the car's cooling system or engine.

Look for signs of any of the four issues we shared with you in this article. fix them. But if nothing seems to change, seek professional help. Get help from a qualified mechanic.

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