How to Fix AC Off Due to High Engine Temp?

When you’re driving on a hot summer day and your air conditioner suddenly turns off, it can be frustrating and uncomfortable. This issue is often caused by high engine temperature, which can trigger a safety feature that turns off the AC to prevent damage to the engine. Unfortunately, this means you’re left without cool air until the engine cools down.

High engine temperature can be caused by a number of factors, such as low coolant levels, a faulty thermostat or water pump, or a clogged radiator. If left unchecked, it can lead to more serious problems like overheating and engine damage.

That’s why it’s important to address this issue as soon as possible. In this article, we’ll go over some common causes of high engine temperature and how they can lead to your AC turning off.

We’ll also provide tips on fixing the problem so you can stay cool and comfortable while driving in hot weather. Don’t let high engine temperature ruin your summer road trips – read on to learn more!

Why is my engine overheating?

If you’ve noticed that your AC turns off when your engine temperature rises, then it’s likely that your engine is overheating. There are many reasons why an engine can overheat, but some of the most common causes include low coolant levels, a faulty thermostat, and a clogged radiator.

Low Coolant Levels

Coolant is essential for regulating the temperature of your engine. Without enough coolant, your engine will quickly overheat. Low coolant levels can be caused by a leak in the system or simply by neglecting to top up the fluid when necessary.

If you suspect that low coolant levels are causing your AC to turn off, then check the level in the reservoir under the hood of your car. If it’s low, then add more coolant until it reaches the proper level.

Faulty Thermostat

The thermostat is responsible for regulating the flow of coolant through your engine. If it’s not working properly, then it can cause your engine to overheat.

A faulty thermostat may be stuck closed which will prevent circulation of the coolant or stuck open which will prevent proper heating by reducing circulation and allowing too much cold water from radiator to cycle through system. You’ll need to replace this part if it’s not functioning correctly.

Clogged Radiator

The radiator is responsible for cooling down hot coolant as it circulates through your car’s cooling system.

Over time, debris and dirt can build up inside this component causing blockages that reduce its cooling effectiveness leading to overheating issues in certain situations like driving on long flat roads with little wind resistance like highways where little air flows across radiator fins and high temps cause thermal expansion making fins bend obstructing airflow even more.

A clogged radiator can cause serious problems with overheating so make sure you clean it regularly as per manufacturer instructions or go to a mechanic for this.

Overall, understanding the causes of high engine temperature can help you identify and fix the problem before it becomes more serious. Regular maintenance of your cooling system can help prevent overheating issues in the future and save you from a potentially uncomfortable ride during hot weather.

ac off due to high engine temp safe to drive
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Symptoms of AC Off Due to High Engine Temperature

When the AC suddenly stops working:

Are you driving on a hot, sunny day and all of a sudden, your car’s air conditioning system turns off? This can happen due to high engine temperature.

When the engine gets too hot, the computer in your car will shut off the AC to prevent further damage. Reduced airflow from vents is one of the common symptoms of this issue.

Warm air blowing from vents:

Another symptom that you might experience when the AC is turned off due to high engine temperature is warm air blowing from the vents. The reason for this is that there’s no cold refrigerant flowing through the system because it’s been shut down to prevent overheating.

Unusual engine noises:

One more sign of high engine temperature and potential issues with your car’s air conditioning system could be unusual noises coming from under the hood. You might hear grinding or squealing sounds as well as hissing or popping sounds. All these sounds can be caused by overheating parts in your engine.

If you notice any reduction in airflow or warm air coming out instead of cold, it might indicate an issue with your car’s AC system turning off due to high engine temperature. Unusual noises can also provide additional evidence that something isn’t working properly and requires attention immediately before causing further damage.

Steps to Fix AC Off Due to High Engine Temperature

Check Coolant Level

If your car’s engine is overheating and the AC has stopped working, the first thing you need to check is the coolant level. Low coolant levels can cause an engine to overheat, which then leads to the AC turning off. The process of checking and topping up coolant is easy, but it’s important to follow a few safety precautions before you start.

Firstly, make sure that the engine has had enough time to cool down before opening the radiator cap. If you open it when it’s still hot, there’s a risk of steam or hot liquid spraying out and causing injury.

Once you’re sure that it’s safe, locate the radiator cap (usually at the front of your engine) and open it slowly. Next, check if there’s enough coolant in your vehicle by examining how much fluid is in the reservoir tank.

There should be a minimum and maximum level on this tank with fluid floating in between these two markers when viewed from above. If you see that it’s low, add more coolant until it reaches the maximum level.

Inspect Thermostat

The thermostat plays a significant role in regulating engine temperatures by controlling how much coolant flows through your vehicle’s cooling system. When they fail or malfunction for any reason, an automobile can overheat; therefore making its AC stop working as well.

Fortunately, inspecting if your thermostat is faulty isn’t difficult at all! You just need some basic tools and knowledge about where this component is located inside your car’s engine compartment.

Start by disconnecting negative cables from your car battery before proceeding with anything else related to this task; then refer to your vehicle manual for instructions specific on how to find its thermostat location. Once found – remove any bolts or screws holding onto this part so that you’re able to access it fully.

Examine its surface for defects such as cracks or deformities, which may indicate that it needs replacement. Alternatively, if there are no visible signs of damage, you can use an ohmmeter to check if the thermostat is functioning correctly.

Clean Radiator

If the coolant level is fine and the thermostat appears to be in good condition; then the next step is to clean your car’s radiator. Over time dirt and debris accumulate inside your engine’s cooling system, causing it to function less efficiently than usual. To clean a clogged radiator using a garden hose or specialized cleaning solution first ensure that your engine has cooled down enough before proceeding.

Next, locate the radiator and unscrew any bolts or clamps holding it in place so you can remove it from its original position. Once removed spray water from a garden hose into both sides of this component to remove any debris that may have built up over time.

If this doesn’t work adequately enough consider using a special cleaning solution designed specifically for these types of issues. By following these tips and tricks – checking coolant levels, inspecting thermostats for defects/damage, and cleaning radiators – you’re well on your way towards fixing AC off due to high engine temperature problems!

Preventive Measures for Future Occurrences

Regular Maintenance Checks

Regular maintenance checks are crucial in keeping your car’s cooling system and other related components in good working condition. It is recommended to have the cooling system inspected at least once a year or as advised by the manufacturer. During the inspection, a certified mechanic will check the coolant levels, radiator hoses, thermostat, and other parts that could affect engine temperature and AC performance.

Driving Habits

Your driving habits can also play a role in preventing high engine temperature and AC issues. Avoid driving on hot days for long periods without stopping to rest your engine.

Also, avoid overloading your vehicle with too much weight as this can cause additional strain on your engine and increase heat buildup. Ensure that you are using a compatible motor oil with your vehicle type and rating.


To prevent future occurrences of AC off due to high engine temperature, it is recommended to install an aftermarket oil cooler or radiator fan that will help keep engine temperatures down when driving under heavy loads or during hot days.


Fixing AC off due to high engine temperature requires identifying the root cause of the problem first before attempting any repairs. Regular maintenance checks of the car’s cooling system can go a long way in ensuring that such problems do not occur frequently.

Additionally, adopt good driving habits like avoiding overloading your car and using compatible motor oils designed for your vehicle model and rating.

By following these preventive measures, you can save yourself from discomfort caused by an uncomfortable cabin when travelling during hot weather due to malfunctioning AC units caused by high temperatures from faulty engines.