AC Off Due to High Engine Temperature (Meaning, Reasons, and Fixes)

If you are driving and observe AC shut off due to high engine temperature message on your vehicle dashboard, you might be curious about the reasons behind it and how to prevent it from happening again. Dealing with the AC turning off in such a situation can be frustrating, but it’s crucial to take prompt action to avoid potential damage to the engine.

AC Off Due to High Engine Temperature

The AC of your vehicle shuts off due to high engine temperature may be caused due to different reasons, including low coolant level, damaged radiator hoses, faulty radiator, faulty water pump, or any other faulty part of the cooling system.

If you come across any worn or faulty parts, it’s essential to replace them promptly. This article explains the major causes of AC off due to high temperature symbol and how to fix it.

What Does AC Off Due To High Engine Temperature Mean?

The AC off due to high engine temperature symbol indicates that the ECM (Engine Control Module) of your car has detected excessive heat in the engine or a malfunction in the cooling fan. This safety feature is designed to prevent engine overheating.

An essential component responsible for managing various engine functions is the ECM. The ECM of your vehicle collects information from sensors positioned throughout the vehicle, processes this information, and controls different functions like fuel regulation, throttle, and ignition angle accordingly.

As the ECM detects an unusually high engine temperature, it initiates an automatic regulation of the AC system, causing the AC to shut off temporarily. This action helps divert more power and resources toward cooling the engine, reducing the risk of overheating and potential damage.

Causes of AC Turning Off Due to High Engine Temperature 

Following are the major causes for an AC to turn off due to high engine temperature:

1) Low Coolant Levels

Coolant Levels

The low coolant level is one of the major causes of engine overheating and AC turning off due to high engine temperature.

Low coolant levels can lead to a faulty cooling system, so make sure to refill the coolant to the recommended level. If you’re uncertain about the location of the coolant reservoir tank or how to refill it, consult the owner’s manual for guidance.

Read More: Low Coolant Level Symptoms and Causes

2) Cooling System Leaks

Coolant Leak, causes of AC Off Due to High Engine Temperature

If your car’s coolant tank doesn’t have coolant, it could be due to a coolant leak. Look for puddles or spots under your car, as coolant leaks can leave visible signs. You can recognize coolant by its sweet smell and color, which may be orange, blue, or green, depending on the type used in your car.

3) Bad Cooling Fan

Cooling Fan

The cooling fan is a crucial part of your car’s cooling system as it helps to expel additional heat from the engine through coolant. It takes in the heat and directs it to the radiator, where it’s expelled into the atmosphere. However, a bad cooling fan can fail to remove the engine heat effectively, potentially leading to engine overheating.

4) Faulty or Clogged Radiator


The radiator is a crucial component in your car’s cooling system, responsible for ensuring a safe engine temperature. Its main function is to remove the heat from the engine coolant and transfer it to the surrounding air, effectively cooling down the engine.

However, when the radiator clogs with contaminants, it hinders airflow, making the heat transfer less efficient.

This situation leads to engine overheating, prompting your car’s computer to take preventive action by shutting off the AC.

Read More: How To Fix a Radiator Leak?

5) Low Oil Levels

Low Engine Oil

In addition to its lubrication properties, motor oil also helps regulate overall engine temperature. Having insufficient oil can contribute to engine overheating issues and force the AC to turn off due to high engine temperature.

6) Faulty Thermostat

bad Thermostat

The thermostat acts as a valve installed at the entry point of the engine’s cooling system. Its main function is to control the coolant flow to keep the engine at the ideal temperature. This is achieved by the thermostat opening and closing based on the engine’s temperature.

When the engine is cold, the thermostat remains shut off, preventing coolant from entering the radiator. Instead, the coolant circulates through the engine’s passages without going through the radiator.

As the engine warms up, the thermostat opens, allowing coolant to flow through the engine’s channels and the radiator, maintaining the optimal temperature.

Read More: Bad Thermostat Symptoms and Causes

7) Problems with the Belts and Hoses

To ensure proper air and coolant flow to and from the engine and relevant parts, it is essential to check and maintain the coolant hoses and belts regularly. Ruptured, blocked, or leaked hoses, as well as worn-out or frayed belts, may limit their effectiveness and potentially lead to unexpected engine damage.

8) Bad AC Compressor

The AC compressor of your vehicle plays a vital role in the air conditioning system by converting refrigerant gas into liquid through the condenser.

When the AC compressor goes bad, it may prevent cold air from entering the vehicle, and refrigerant won’t move through the AC system. As a result, the engine temperature may increase, leading to the AC turning off.

9) Faulty Water Pump

Damaged Water Pump, reasons of AC Off Due to High Engine Temperature

The water pump of your car is responsible for circulating the coolant from the radiator to the engine and vice versa. If your coolant is contaminated, it may block the flow through the pump, leading to potential overheating problems.

Read More: Bad Water Pump Symptoms and Causes

10) Faulty Engine Coolant Temperature Sensor

A bad coolant temperature sensor (ECT) may also cause your vehicle computer to trigger the AC off due to a high engine temperature message.

This sensor plays a key role in regulating the temperature of the coolant and transfers this information to the ECM. The ECM then makes adjustments to various parts to maintain the engine at the ideal temperature.

When the coolant temperature sensor goes bad, the cooling fan may not operate accurately, leading to engine overheating and turning off the AC.

11) Blown Head Gasket

Head Gasket is Blown

The head gasket is a crucial component of the engine, typically made of aluminum, rubber, or steel. It forms a seal between the engine block and the cylinder head, preventing the oil and coolant from mixing with each other.

A blown head gasket is a severe problem that can lead to various engine issues, such as turning off the AC due to a high engine temperature. This issue appears when the gasket develops a leak, causing coolant to escape and mix with oil or exhaust gases.

As the gasket becomes damaged, it results in coolant loss. As the coolant level decreases, your engine overheats, which activates the AC off due to the high engine temperature warning. Addressing a blown head gasket promptly is essential to prevent further damage to the engine.

How to Fix AC Off Due to High Engine Temp?

Follow the below-given steps to fix the AC off due to high engine temperature:

  • Start by checking the coolant level and top it up if it’s insufficient.
  • Properly inspect your radiator for a blockage. If you suspect radiator problems, consider seeking professional repairs from a mechanic.
  • Inspect the radiator for signs of corrosion, leaks, or wear that may hinder its cooling ability. Replace it if needed.
  • Check the performance of the radiator fan. If it is damaged, replace it.
  • Check all hoses connected to the cooling system for any signs of damage or leaks. Repair or replace the damaged hoses.
  • Check the head gaskets. If the gasket is blown, replace it.
  • Check the engine oil. If your oil looks low, add more.
  • Inspect the thermostat for damage. If it is damaged, replace it.
  • If, after inspecting all parts above, the problem persists, there might be a more significant underlying issue with the engine itself. In such cases, it’s best to consult a mechanic thoroughly examine the engine.

FAQ Section

Should I turn off the AC if my car is overheating?

Yes, if you notice your car overheating while driving, the first step is to turn off your AC. While the AC is working, it adds additional strain on the engine, which can worsen the overheating issue.

Why is my car engine temperature high when AC is on?

The air conditioning system of your car puts additional strain on the engine due to that engine needs to work harder, causing engine overheating. Your engine may also overheat due to a faulty cooling fan.

Does running AC increase engine temperature?

Using the AC cycles during hot weather puts an excessive load on the engine, producing additional heat. The engine’s serpentine belt drives the AC compressor, consuming more energy from the engine and contributing to increased heat.

What are common Chevy Cruze AC problems?

For a Chevrolet Cruze, common reasons for the AC to turn off include a faulty AC compressor, low coolants, electrical climate control problems, or refrigerant leaks.  

Can you drive with AC Off due to a High Engine Temperature message?

If your car’s AC turns off due to high engine temperature, it is not recommended to continue driving. When the AC Off due to high engine temperature warning light illuminates on your dashboard, it is a serious matter that requires immediate attention. This message represents that your engine’s temperature has risen to a dangerous level, and as a preventive measure, your AC has been turned off to avoid further damage to your vehicle.

Does turning on the AC help cool down the engine?

The AC of your vehicle plays a crucial role in regulating the cabin and engine temperature, preventing engine overheating, and ensuring a smooth journey without any roadside breakdowns.

How to avoid AC turning off due to high engine temperature? 

To prevent the air conditioning from shutting down due to high engine temperature, make sure your car’s cooling system is well-maintained. Regularly check the fans, hoses, thermostat, and radiator for any issues, and ensure the coolant is inspected and refilled as needed.

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