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  • Writer's pictureAleko Kavouras

What to Do if Your Car AC Stops Working

Updated: Apr 28, 2021

It’s summer, it’s hot and your AC is barely blowing enough cold air to cool your finger. Or worse—it’s blowing hot air on top of already humid 90-degree weather. What do you do? Don’t panic, our Maryland auto AC repair specialists are here with an action plan.

Common Car AC Problems

  1. No air is coming out at all when you turn AC on

  2. The air is warm or hot, although the setting is on AC

  3. The air is cold but is barely coming out even when you switch to Max AC

  4. Changing the settings doesn’t adjust the air temperature or airflow

If any of the above sounds familiar, there is definitely something wrong with your vehicle’s AC system. Here is what to do if you run into these problems.

Contact Your Trusted Maryland Mechanic

OK, this is probably not the advice you were looking for, but it’s the best thing you can do if you have minimal technical knowledge about your car. Your vehicle’s AC system consists of multiple components, such as compressor, condenser, evaporator, fan, the refrigerant line and a web of tubes and hoses. If you don’t understand how this cooling system operates, you won’t be able to accurately diagnose the problem.

Besides, AC system components may be hard to reach depending on the make, year and model of your vehicle. In some cars you have to remove parts of the dashboard, and you would definitely need to know your way around under the hood. If this sounds like too much trouble, contact Maryland car AC repair specialists at Hillmuth and we’ll be happy to help.

Check and Replace the Cabin Air Filter

Your vehicle has two air filters. One is located under the hood and its purpose is to clean the air before it’s mixed with the fuel for more efficient combustion. The other air filter is inside your car’s cabin and is placed there to catch any contaminants before the air enters your cabin during heating or cooling. If you are having airflow problems, they may be caused by a clogged cabin air filter. And because a clogged filter makes it more difficult for the fan to move the air through, the fan motor may eventually burn out and you will get no air at all.

Replacing a cabin filter can be a DIY project in some vehicles. The procedure itself is easy, but getting to the filter can be complicated. A cabin air filter can be hidden anywhere behind your vehicle’s dashboard. They are often found behind glove compartments, as well as at the bottom of the center console next to the gas pedal. Expect to be stuck in some uncomfortable positions while trying to reach the filter. Cabin air filters should be replaced every 15,000 to 25,000 miles or as your vehicle’s manual indicates. Be sure to purchase the right filter for your car if you are replacing it yourself.

Common Causes of Auto AC Problems

If you want to investigate further or simply want to understand what could be wrong with your vehicle’s AC, here are a few possibilities:

  1. Clogged condenser

  2. Leaking evaporator due to rust or broken welds

  3. Clogged evaporator fins

  4. Burnt connectors or corrosion in the fan relay

  5. Failed fan motor

  6. Rusted pressure switch

  7. Stuck expansion valve

  8. Failed compressor (check if it’s spinning when the AC is on)

Keep in mind that a low refrigerant charge is not always the problem. It shouldn’t be a problem at all unless there is a leak in the system. Don’t go to the auto parts store and buy a refrigerant recharge kit. Unknowingly overfilling can be more harmful than letting the refrigerant run low. Besides, if you have a leak, you will be filling a bottomless bucket. Take your car to Hillmuth where our experienced techs have solved thousands of auto AC problems and will be glad to take a look at yours.

Schedule your appointment today with one of our Maryland auto repair shops in Columbia, Gaithersburg, Glenwood or Clarksville.

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