Updated at: 28-03-2022 - By: Lucas

AC in a car is wonderful. In addition, it provides relief from the oppressive heat. And, as is customary, you turned on the air conditioning, only to discover that the house is unusually warm.

If this happens, you may need to visit your mechanic.

A problem with the compressor, pump, or condenser is almost certainly at blame if your car only begins to overheat after you’ve turned on the air conditioning.

A damaged compressor can cause your call to overheat, making your condenser and pump useless. Overheating is a possible side effect.

If you see any of the following symptoms, do not use your air conditioner until it has been repaired.

A hot dashboard and seats are signs that your car’s air conditioner is working too hard, which causes it to overheat.

Why does my car overheat with the a/c on?

The Compressor Is Under More Stress

Cooling that Doesn’t Work

The Fan Won’t Work

A malfunctioning temperature sensor

faulty parts in a car

There are numerous reasons why a car may overheat, especially if the AC is running. Overheating is a serious problem that can cost a lot of money to resolve.

Check out what’s causing your car to overheat, especially with the AC on.

5 Causes Of Overheating When AC Is On

Car Overheat When AC Is On-2

1. Greater Load On The Compressor

The AC system requires a lot of power from your car’s engine and generates a large amount of pressure on the compressor, which the compressor is unable to handle. This is a known truth. Engine rotation is also influenced by compression.

The compressor overloading is the most prevalent cause and is a serious issue.

Your air conditioner’s compressor behaves and operates like an engine the instant you turn it on. As a result of this, the compressor adjusts the refrigerant cylinders to compress them.

Because of this, the engine is under a lot of stress. Overheating occurs when the compressors are under greater stress than they can tolerate.

Checking for overheating is the only way to know for sure if this is a problem. If this is the case, call your car’s mechanic right away.

2. Ineffective Cooling

Since it plays such an important function, cooling the condenser is the primary goal of any cooling system installation.

When you switch on the air conditioner, the condenser is filled with liquid refrigerant.

The condenser heats up, and the engine fan blows on it to keep it cool.

A clogged engine fan, on the other hand, will cause the condenser’s temperature to rise rapidly, ultimately leading to engine overheating.

In addition, the condenser or radiator tubes becoming blocked can cause your engine to overheat for another reason.

Corrosion particles or rust can clog the pipes when the liquid moves through them.

Overheating will result as a result of the coolant and refrigerant becoming clogged and not being able to flow properly.

As a result, clogging is a serious problem that must be addressed immediately.

Finding out what’s causing your car’s overheating problem may be as simple as looking at the radiator and condenser.

3. Malfunctioning Fan

When the engine’s cooling fan isn’t working properly, your car will overheat. A broken engine fan can cause your automobile to overheat even at modest speeds.

When the condenser or radiator does not have enough airflow, this problem occurs. The radiator and condenser may be clogged, or the fan’s fins may be obstructed.

It’s also important to check the switch on your fan. Don’t forget to replace your old fan. Many problems might arise in a vehicle due to faulty fans.

4. Faulty Temperature Sensor

Car Overheat When AC Is On-3

Temperature sensor failure is extremely unusual, yet it is not completely ruled out.

The coolant temperature can be monitored using these sensors and compared to an indicator mounted on the dashboard, if necessary.

Engine overheating could cause it to display abnormally high numbers, so you never know. If you notice any of these concerns, check the thermostat.

This is an extremely rare occurrence, but you never know.

Contact your mechanic as soon as possible to get this taken care of.

5. Defective Car Components

Defective automotive parts are quite common, however after time they lose their effectiveness and begin to fail.

When you turn on the AC, your automobile overheats because of the malfunctioning components.

Your car’s temperature may go higher if the elements like refrigerant, condenser, compressor, and evaporator don’t perform as they should.

Your car’s air conditioning system should be checked out on a regular basis to avoid these problems.

7 Solutions To Overheating When The AC Is Turned On

1. Refrigerant Compatibility

You should always verify that the AC refrigerant you use is compatible with your car.

AC refrigerant compatibility is a common issue, and it can have a negative impact on your vehicle’s AC system.

Because of this, you should check the refrigerant in your car. A little assistance from your technician, or even some basic knowledge of gears, will allow you to perform this task.

2. Inspect The Radiator

As far as cooling systems go, the radiator is the most important part. Testing kits are available to see if the radiator cap is working properly.

You can tell if the radiator is leaking by checking it. Don’t forget to top off the radiator with coolant.

3. Replace The Antifreeze

Aspirin with Kool-Aid

The engine’s coolant is a clear, green liquid that aids with temperature control.

High heat capacity and corrosion prevention are two of its many benefits. That is not to mention how much longer it will last for your automobile.

Changing your antifreeze or coolant every two years is the best way to avoid overheating problems.

4. Flush The Trapped Air

The air trapped in the coolant system might raise the temperature of your car on occasion. Discharge any trapped air by performing a coolant flush.

5. Check The Compressor

If you hear any noise coming from your AC compressor, use a multimeter to check the voltage in the cables. Alternatively, if damage is found, a new compressor should be installed.

6. Check The Pump

It is the water pump’s job to circulate the fluid from the radiator and deliver it to the engine in one continuous motion.

Ensure that the pump is in good working order. If so, fixing them should be your top priority.

7. Check The Fluid Levels In The Radiator

You can stop the car’s engine if it begins to overheat by putting the ignition key in the ignition. Observe the radiator fluid levels when the engine has cooled down before opening the hood.

Replacing and adding coolant and distilled water if it’s low (50-50). Regular tap water will not do.

When your automobile overheats, you should avoid using the air conditioning until the problem is resolved.

What Should You Do When Your Car Overheats With Ac On In Traffic?

You get frustrated and stressed when you’re trapped in traffic.

But do you know what’s even worse?

Overheating, your car is sweltering, and your air conditioner has been turned on. It’s a new kind of adventure. It really is as bad as it sounds.

Get this under control by following the instructions below:

It’s best to pull over as soon as you notice your car’s engine is overheating while the AC is running.

It occurs frequently in locations where parking isn’t an option. The engine may run more smoothly if the AC is turned off when you’re in a hot state. Even so, see if you can pull over and put your vehicle in neutral.

You’ve seen drivers pull over and open the hood of their vehicles. When stuck in traffic, many individuals resort to this method of keeping their engine cool. Overheating can result in the release of steam. Wait for the hood to cool off before opening it if it’s getting too warm. This will aid in the release of the accumulated heat.

Turn off your car’s engine, but keep the ignition key in the ignition. A running fan will keep everything cool if you leave the ignition key in the on position. Assuming, of course, that you can hear your fan spinning. If not, the fan may be to blame for your overheating.

Your vehicle will cool down in about 30 minutes. It’s important to examine the radiator for leaks as soon as the engine has cooled down. This is a fast check of your vehicle’s system.

Consult your technician if you see any leaks or loose clamps, and he or she will be able to assist you in making the necessary repairs.

How Does A Lousy Thermostat Affect My Car?

Your automobile may overheat if you have a faulty thermostat. The temperature of liquids is controlled via a valve in the cooling system.

The coolant may flow freely through the system, which helps keep the components at a comfortable temperature.

Overheating, poor engine performance, and temperature swings are all symptoms of a faulty thermostat. As a result, it won’t provide you with accurate results.

How Does A Faulty Compressor Affect My Car?

Your car’s engine can overheat if the compressor is defective. If your car’s compressor seizes for whatever reason, the belt won’t be able to do its job.

When you turn on the engine, the belt acts as a link between the clutch and crankshaft.

Your car’s belt is critical to its operation, yet you can drive it without it. In the end, you’ll have to deal with overheating issues.

Is It Essential To Get My Car’s Air Conditioning Unit Recharged?

You can’t see or hear anything outside the AC unit. It’s possible that your AC’s Freon is running low if you notice that it’s not blowing cold air. Using this guide, you’ll learn how to check the Freon level in your vehicle.

In addition, because AC systems are highly pressured, leaks may develop over time. It is necessary to recharge an AC unit when its Freon and pressure levels decline.


Today, the problem of a car overheating when the air conditioning is on is widespread. This is a widespread problem in today’s automobiles.

I’ve covered the most common causes of a hot car in this article. In addition, I’ve offered a method for determining which component is faulty.

The longer you wait to solve a problem, the greater the dangers it poses to your vehicle and the greater the damage it will do if you don’t fix it right away.

To keep this from happening, I recommend that you establish a regular schedule for performing a comprehensive engine check. You’ll save money and ensure the safety of your vehicle and your family at the same time.