Signs Your Car’s AC Needs A Repair

Signs Your Car’s AC Needs A Repair

Finding yourself sitting in a hot car because your air conditioner no longer works is not a happy experience. If temperatures are soaring and you have a long way to drive, this is even worse. Thankfully, you may be able to prevent this scenario from happening if you pay attention to some signs that your car’s AC unit needs a repair.

Car AC Repair – Understanding Your AC Unit

An air-conditioning unit is a straightforward system with six components. A condenser, a compressor, cooling fans, and hoses make it operate. It utilizes electrical parts and requires a refrigerant to cool the air.  If issues arise with any one of these six components, your system will stop working as it should.  Below is a list of possible problems with a car’s AC.

Refrigerant and Hoses

If the refrigerant is low, your air conditioner will not cool the air as effectively as it normally would when the system is full. Refrigerant breaks down over time.  Therefore, it will decrease as your vehicle ages. The refrigerant level may also decrease due to a leak.

The most common area where leaks occur is the hoses that move the fluid through the system. As your vehicle ages, these hoses can become weaker and crack or split. The fittings connecting the hoses to the mechanical parts may also loosen with time.  All of these possible issues will cause a leak in the system.

The refrigerant must be full while your vehicle is operating. The refrigerant also contains a lubricant that helps all the other parts of your AC system function properly. When the level is low, you place the rest of your system at risk for damage.

Compressor and Condenser

The compressor is a mechanical part that takes in air and compresses it with the refrigerant. The unit then pushes the compressed air out of the unit into the condenser.  Here it expands and becomes cold and is then circulated through the vehicle.

Both of these mechanical parts rely on the other to operate correctly. As with any piece of machinery, interior and exterior moving parts can wear down with time or break, which can lead to a failed AC system.


There are fans inside your vehicle that move the cooled air around. These fans are located behind the dashboard and usually near the front floorboards. Some cars have fans that also circulate air in the rear seating areas. If these fans stop operating, the air will not move through the vehicle.

If you have items on your floorboard, the airflow from your fans can get blocked and can sometimes cause the fans to break. Even if the fans continue to operate, the airflow through the vehicle can become severely restricted.


There are many different electrical components that are associated with your air conditioning unit. If any of these systems are not working correctly, the unit will not work. It may be something as simple as a blown fuse or damaged wiring. However, if you suspect electrical damage of any kind, you are encouraged to take your vehicle to a mechanic.

Indicators That Your Air Conditioning Unit May Be Failing

Air Is Not Cold

Temperature is the most obvious indicator that the AC unit is not working. If your unit is blowing warm or hot air, you probably you need to have your refrigerant refilled on your vehicle.

If you are a DIY person, make sure that you know what type of refrigerant is in the vehicle before adding any more. Older cars probably use a different type of chemical compound than newer vehicles. Many of the old refrigerants are no longer available on the market.

It is also important to add lubricant to the mixture as well. Adding lubricant ensures that the mechanical parts are cared for while your vehicle is operating.

It is always in your best interest to have your unit refilled professionally.  Adding the wrong chemical mixtures can destroy your AC unit and potentially damage your vehicle.

Bad Smell

If you turn on your AC unit and there is a foul odor, there may be a few different issues. If it smells like burning, it may be electrical and should be taken to a mechanic right away.  If the smell is like something rotten, your filters may be clogged, or there may be mold and mildew buildup in your unit. This is fixed by having your system flushed and your filters changed.


Your AC unit should run fairly quietly. If you are hearing clanking, grinding, or any other unusual noises, you are in need of repair.

Water on the Floorboard

Your AC unit is designed to drain outside of the vehicle. If you see water pooling on your floorboards near the vents, this is an indicator that your outside drains are blocked. With time, this can lead to debris filling your system and potentially damaging the entire unit.

Signs Your Car’s AC Needs A Repair

Older Cars Need The Most Attention

If you are purchasing a used vehicle, it is important that you check the air conditioning unit before making your purchase. Look for signs that the unit is not performing properly. If the air is not cool enough, ask to have the system charged before purchase.

Caring for the AC unit in your vehicle is necessary, but also easy. Replacing or repairing these units can be very expensive if you do not catch the problems early before they prevent the entire system from working.  Use the information above as your guide to maintaining your AC properly.  VINsmart hopes you stay cool on the road!

When Purchasing A Vehicle

Always remember to run a VINsmart report on any used vehicle before making a purchase.  A VINsmart report runs a complete history on the vehicle including whether it has ever been reported as stolen, involved in a major accident, or listed as a totaled vehicle.

VINsmart reports will also give you a registration history and mileage at registration.  It reports any significant incidents related to the vehicle, such as being involved in a fire or flood.

When you are going to purchase a used vehicle, the best way to ensure you are making a good purchase is to know the vehicle’s complete history.


To get started with VINsmart, click here.

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