What Are the Symptoms of a Bad AC Compressor Relay?

Air conditioner in compact car

Your car is a major investment. And like any investment, you want to enjoy the benefits of owning a car for as long as possible before you start to see damage or need to repair your vehicle.However, unlike other investments, you may expect that one of the wiring or electrical systems in your car may give way.

For instance, if you suddenly find that your car’s air conditioning system is blowing out warm air or does not produce the same level of cold that it could when you first bought it, chances are the damage is in your AC system’s electrical relay. In most cases, the damage is due to the electrical contacts wearing thin or burning out and will need replacements. It’s easy to spot when this happens when you understand how your car’s air condition works and what symptoms indicate that it is malfunctioning.

How Your Car’s AC System Works

Different vehicles use various types of air conditioning systems, but most of these systems follow the same cyclewith three main parts to operate: the compressor, the condenser, and the evaporator. The cycle starts at the compressor, where cool, low-pressure gas converts into hot, high-pressure gas. The gas follows a tube connected to the condenser, where it is cooled into a high-pressure liquid. It passes through a receiver or dryer, where it filters out pollutants that could contaminate the coolant.

From there, the liquid enters the expansion valve, where it becomes a cool, low pressured-liquid. Then, it enters the evaporator and becomes cold air. The cold air chills the evaporator’s walls, and a blower motor pushes this cold air out to the car’s dashboard and vents. The rest of the air inside the evaporator returns to the compressor and repeats the cycle again.

Symptoms of a Bad AC Compressor Relay

No Cool Air at All

vehicle's airconA major indication that the AC relay is failing is the lack of cold air blowing out of your system. It’s normal for your air conditioner to blow warm air when you switch it on, but this should turn cold within a matter of seconds. If the relay is defective, the compressor will hardly operate, and your AC will lose its ability to circulate cold air.
While multiple reasons can cause your vehicle’s AC to fail, faulty relays are the most likely culprits. This is where a mechanic who provides car repair in Salt Lake City and other parts of Utah should begin checking.

Symptom: The Compressor Doesn’t Turn On

When you switch on your air conditioner, you might hear a familiar clicking sound before the air starts blowing out. On a regular day, the air conditioner blows out warm air for a few seconds before it begins to get colder. But if you turn on your AC and it doesn’t seem to get colder or work at all, you might also notice that the clicking sound is not there anymore.
The clicking sound comes from the compressor switch’s clutch. If it’s not clicking, it means it’s not getting power and it has a failed relay.

Cooling Inconsistency

vehicle's airconYour AC compressor needs power from the relay to operate; otherwise, the air pressure weakens, and the system will fail to cool air properly. If you notice that your car’s AC is working but shuts off without warning the next minute, or if there are instances where it works normally and then blows out warm air a few minutes later, this might be a sign of an  a failing relay.


Repairing and Recharging Your AC System

In case of a bad AC compressor relay, you’ll want to visit your trusted mechanic or, if you have the skills for it, repair it yourself. Damage to the system could mean replacing one or more parts. At best, however, it could also mean that your system is running low on coolant, the fluid that creates cold air. If you don’t know how to replace it yourself, it should be a fast trip to a car technician to help you out.At least, by visiting one, they can help you determine if there is any other damage that could be affecting your vehicle’s performance.

Avoiding Damage to Your Car’s Air Conditioner

Replacement or repairs, however, will cost you money unless your car is covered for the service.While it’s inevitable that your car will undergo wear and tear with regular use, it’s possible to prolong your AC system’s lifespan without the need for repairs or replacement.

ICar’s Air Conditionerf you have a new car, remember to follow its scheduled maintenance regularly. This helps mechanics keep it clean and running at its best for as long as possible.Avoid leaving your car under the sun for so long because turning on the air conditioner while the interior is hot may lead you to overuse the AC. Don’t start the air conditioner when you’re driving beyond 35 miles per hour because this could harden the compressor and damage it.

Keep your car’s interior clean from pollutants. These particles could get into the AC system and damage the filters.

AC units are vital components of any vehicle, but they may begin to wear down with use. If you feel that your air conditioner is beginning to fail, it’s best to have a technician diagnose your system to know the exact source of the problem.