When it comes to what causes car air conditioning failure, there are countless possible options. However, there are some issues that we see more regularly than others. In this post, we go over some of the most common causes of car air conditioning failure. We’ll also cover how to possibly prevent them from occurring in the first place.
Now just a reminder, AC systems vary from car to car and every car has a different history. So these suggestions may not apply to everyone’s situation. If your car’s air conditioning system isn’t working as well as it used to, it is best to get your vehicle inspected by a licenced technician.
Refrigerant Leaks
The most common cause of air conditioning faults is a leak in the AC system. The air conditioning system in your car is designed to be a completely sealed unit. So if the system is low on gas there is a leak or fault somewhere in the system. This is very common in older cars. Over time hoses, seals, valves and other components such as the condenser and evaporator can break down and develop leaks.
When your AC system is low on gas it may present as uneven temperatures across the vents, there may be a hissing noise or the air from the vents may not be as cold as usual.
A leaking seal in the system can be difficult to detect which is why we recommend getting your AC system serviced regularly. As part of the service, we pressure test the system and inspect thoroughly for leaks. We also use a UV dye in all our AC services to make identifying any leaks easier at future inspections.
Blocked Filters
If you notice a bad smell or reduction in airflow in your AC system, it could be a sign of a blocked cabin filter (also known as a pollen filter). Over time the pollen filter can become clogged with dust, leaves, twigs and residue from exhaust fumes. When the filter is blocked it can put unnecessary strain on your AC blower motor and evaporator. Left clogged or blocked, it could potentially cause costly problems to your vehicle’s AC system.
We inspect the cabin filter as part of our standard AC service. In most cases, we recommend replacing the cabin filter every couple of years, depending on how you use your vehicle.
Thermostat/Thermistor Fault
Uneven temperatures in the cabin can possibly be the result of a faulty thermostat or thermistor. Usually, this is repaired by replacing the faulty component. If you have an older vehicle with a manual AC system, uneven temperatures may also be caused by a faulty control switch, temperature sensor or pressure switch. If you suspect your thermostat may be faulty, we suggest getting your AC system tested by an auto electrician.
Compressor Fault
If there are some irregular noises coming from your vehicle when your AC is turned on this may be due to a compressor fault. If the system is low on gas or lubricant as a result of a refrigerant leak, this can affect the functionality of the AC compressor. If you suspect there may be an issue with your compressor it is best to get your AC system checked by a professional and licenced technician.
Electrical Fault
As cars become more advanced, more systems in the vehicle are controlled electronically. The AC system in your vehicle is no exception. Modern AC systems now incorporate more electronic components to improve performance, efficiency and passenger comfort. This has, in turn, increased the scope of many AC diagnosis and repairs. An Air Conditioning system may be perfectly fine mechanically, but an electrical fault may prevent it from functioning properly. If your AC system stops working suddenly it may be caused by an electrical issue.
Diagnosing AC System Faults
Unfortunately, AC issues are not always a cut and dry diagnosis. A car’s Air Conditioning System is made up of over 100 different components. This makes it very difficult to diagnose issues with 100% certainty. If your AC system is not performing as it should be, your best bet is to get your car inspected by a qualified auto-electrician as soon as possible.
At Accelerate Auto Electrics we specialise in all types of vehicle air conditioning systems so we can repair just about every type of system you can think of. All of our technicians are fully qualified Auto Electricians and licenced with ARCTick. With over 40 years of combined experience, our team has the knowledge and training to diagnose and repair all types of vehicle AC systems.
If you have any other concerns, issues or questions about your car’s AC, our technicians are on hand. Feel free to give the team a call on (07) 5479 6622 or contact us online here.