Car AC Off Due To High Engine Temperature (Fixed)

Car engine overheated and AC turned off automatically, both are serious issues. Is your car display showing AC off due to high engine temperature massage? Your car can show this error message due to a damaged thermostat, faulty temperature sensor, bad AC compressor, or low coolant level.

After having this warning message, cool down the engine first, visually inspect it to determine the root cause, and hire an expert to repair or replace damaged parts.

What Does AC Off Due To High Engine Temp Mean?

A car’s AC is off due to a high engine temperature symbol when the PCM detects an excessively heat engine or malfunction in the cooling fan. The car’s computer system turns off the AC to reduce the engine’s pressure and prevent it from overheating.

Causes of Car AC Off Due To High Engine Temperature

Your car may also display this concerning message due to plenty of reasons including a worn radiator, dirty air filter, leaking hoses, or leak in the coolant tank. At a time, your older car’s engine temperature gauge may fluctuate while modern models activate warning lights.

Major faults that can make your car’s engine overheat and cause the AC to turn off:

1. Worn-out Thermostat

The thermostat is placed between the radiator and the engine. It controls the operating temperature of the engine and prevents it from overheating. It also synchronizes the cooling fluid and allows the fluid to enter the engine once it becomes hot enough.

But if the thermostat is worn out, obstructed, or damaged, the coolant won’t enter into the engine, resulting in overheating.

You can check the thermostat by putting it in warm water after removing it from the car. If the thermostat’s valve is open, it is still in good condition. Otherwise, you have to replace it though it isn’t much expensive.

2. Faulty Temperature Sensors

Temperature sensors measure the fluid’s temperature for the ECU. The engine can overheat and be forced to turn off the ac due to a faulty water inlet temperature sensor or bad coolant temperature sensor.

The radiator fan may also stop working due to a damaged coolant temperature sensor and make the engine overheat. If so, your vehicle will produce excessive black smoke.

3. Bad Temperature-Sensing Circuit

A loose, corroded, or worn-out temperature-sensing circuit can affect the temperature reading force the sensor to malfunction, and cause the engine to overheat. It can happen due to oil residue and grime build-up on the connection point or loose electric wiring.

4. Damaged AC Compressor

A faulty AC compressor prevents the refrigerant from into the AC system and makes the engine temperature unstable. Hence the AC can be turned off and you notice an error message on the display.

5. Leak in Coolant Level

The car’s cooling performance is low due to insufficient coolant level caused by leakage or blockage. It can increase the engine’s temperature and turn off the AC.

To inspect, open your car’s hood and check the coolant level. If there is insufficient coolant, add some. At a time check under the vehicle for a wet place to find the exact fluid leaking. You should also check both radiator hoses, rubber coolant lines, thermostat housing, and water pump and make sure these are in good condition.

6. Blown Head Gasket

A damaged or broken head gasket forces the engine to work harder to produce the required power. A blown head gasket also causes the vehicle to drop coolant level quickly and affects the engine cooling system, resulting in the engine overheating.

Malfunction in the water pumps, insufficient engine oil, or a damaged oil pump can also encourage your car’s ECU to activate AC off due to a high engine temp error message.

Can You Drive A Car with AC off Due to High Engine Temperature Massage?

You shouldn’t continue driving the car with this error message particularly when it indicates an overheated engine. The first thing you must do is cool down the engine. Activate the emergency light park the vehicle to the roadside immediately and stop the car. Wait for around 20 to 25 minutes so the engine can cool down.

Then open the car hood carefully as the fluid will still be very hot and inspect the engine. Check the temperature gauge, cooling fan, radiator, and coolant reservoir for leaks and damage. Don’t touch any component or water as it can burn your skin.

Turn on the park mode on the car and rev the engine to restore the functionality of the water pump and fans. It’ll help cool down the engine quicker. Once the engine cools down, you can bring it to the home garage or nearest automobile repair shop.

Troubleshooting Car AC Off Due to High Engine Temperature Problem

If your car’s displaying AC off due to high engine temperature massage, the first thing you should do is check the coolant temperature. Then check if the engine overheats. If it is, inspect the upper radiator hose.

Determine if its temperature is the same as the lower radiator hose or different. If you find the temperature is different and isn’t much hot, replace the thermostat. But if the temperature of the engine is normal and you are still getting the error message, replace the thermostat switch of the AC.

You can also have this warning message due to using a defroster that works with AC and a heater to dry off the frost. So it’s better to leave the job to the expert mechanic for deep diagnostics even if it costs around $900.

How To Fix AC Off Due to High Engine Temp Error Message

Below are some helpful tricks to keep the engine cool and avoid having ac off due to a high engine temp message on the display:

• Crank up the heat using the maximum setting as it’ll pull away the heat from the engine.  
• Remove the radiator cap from under the hood and add coolant till the recommended level. To make the process safer, cover the radiator cap using a towel, push it down, and make a quarter turn slowly. This will help release the pressure safely and avoid spraying boil coolant on your face.
• If the damaged radiator causes a coolant leak, flush all the coolant to find out the cracks and holes. Then repair the cracks or replace the radiator if needed. Then refill the tank and check the temperature gauge as it should be in the recommended range.
• Check the air filter and replace it if it becomes dirty. You can also clean the filter and reuse it for a short time.
• Replace or fix temperature sensor if it is beyond repair.
• Remove obstructions from the blocked thermostat valve or replace it to be more relaxed.
• Tighten the radiator cap firmly and replace it if it wears out badly.

FAQs

Final Words

If you notice car AC off due to high engine temp on the car dashboard, stop driving and try to cool the engine down. It can prevent further damage and possible accidents. However you can continue driving once the engine is cool, you should bring the car to the repair shop.

Ignoring this warning message can damage both the AC system and the engine. However, you can fix the issue at your home garage following the tips mentioned particularly if you have a reliable hand and some skill.