Everyone wants cold air conditioning when driving in hot weather. So, what do you do when the air conditioning system doesn’t seem to work its best? If you know the bad AC compressor clutch symptoms, you can tell if this part has failed, or if there’s something else going on.
In this guide, I cover the top symptoms and show you where to find the AC compressor clutch. I also help you test it and explain its function. Finally, you will get a look at the average AC compressor clutch replacement cost before I answer your biggest questions.
Symptoms Of A Bad AC Compressor Clutch
When the AC compressor clutch goes bad, the air conditioning may not work at all or it can work intermittently. There may also be loud noises from the compressor or the clutch will stop moving. When this happens, the air may be stuck on or off, plus refrigerant can leak.
1. AC Might Not Be Working At All
The biggest sign is that you stop getting cold air from the air conditioner. If you don’t feel any cold air coming from the vents, you may think it’s a lack of refrigerant, only to find out that the compressor clutch is to blame instead.
With that said, there are a lot of reasons why cold air may be lacking. For that reason, a complete diagnosis is needed before replacing parts.
2. AC Might Work For A Short Time And Then Stop Working
Before the AC quits completely, it might work intermittently. With a compressor clutch not engaging all of the time, you may get cold air occasionally, and it could fail at other times.
Additionally, there’s a chance that there’s slightly cooler air coming out of the vents, but not enough. Either way, you should start diagnosing the problem before issues get worse.
3. Loud Noises From The AC Compressor
As the compressor clutch fails, strange noises occur. This noise may start before there are any other symptoms, giving you a heads-up.
The noise can resemble a squealing that occurs, especially when it first starts running. Additionally, this noise can indicate trouble with the bearings.
4. Clutch Stopped Moving (Visually)
If the AC compressor clutch won’t engage, the clutch is going to stop moving. When it doesn’t engage, you won’t be able to get any cold air from the system.
If the clutch fails to disengage, the AC will remain on when it shouldn’t. If left unrepaired, it can cause damage to the serpentine belt, so you don’t want to put off fixing it.
5. Inability To Turn Air Condition On Or Off
If the clutch seizes up, as discussed above, the compressor can remain activated or deactivated. You may not be able to turn on or off the air conditioner, no matter what selection you make on the control panel.
In most cases, the air conditioning compressor clutch is going to break in a way that renders it impossible to get cold air flowing. However, it’s not impossible for the opposite to be true.
6. Leaking AC Refrigerant
You may also notice refrigerant leaks if the compressor clutch starts to fail. When the clutch isn’t working correctly, the front seal can start to leak.
Car AC refrigerant will leak through the small openings. Depending on how bad the leak is, the cooling capacity will be hindered.
Reasons The AC Compressor Clutch Won’t Engage
The compressor clutch might fail to engage for other reasons besides a simple malfunction. Consider these possibilities as well:
1. Blown Fuse
The AC compressor runs off of a fuse. If the fuse blows, the compressor cannot get the power it requires to run.
In this case, you would need to replace the fuse with a like one. Make sure the amperage matches up with the one that was blown.
2. Faulty AC Pressure Switch
Several switches are needed to activate the compressor clutch. A malfunction with any of the switches can cause it to remain disengaged.
The most notable possibilities include the low or high-pressure switches, as well as the evaporator temperature sensors. With failure at any of these switches, the AC compressor may not turn on.
3. Faulty Wiring
The air conditioning system in your car is made up of several connectors and wires. Signals are sent through these connections to activate the compressor.
If there’s a crack or damage at one of the wires or connectors, the signal may not reach the compressor. The only fix would be to repair or replace what’s damaged.
4. Incorrect Refrigerant Charge
For the air conditioning to work correctly, the refrigerant must be charged to a particular level. When the system is overcharged, the high-pressure switch disables clutch operation.
On the other hand, there could be a malfunction without enough refrigerant. The low-pressure switch is made to cut power to the compressor clutch without enough pressure.
Testing The AC Compressor Clutch
When the AC compressor doesn’t engage anymore, one problem could be the clutch. To check for this problem, you need to pay close attention to your car’s RPM gauge. Follow these steps:
- Turn on the AC system.
- Watch the RPMs for an increase. You should see an increase when the system is first switched on.
If you don’t see an increase, there’s something wrong with the AC compressor, keeping it from turning on.
You can also use your senses to further diagnose the compressor clutch. For example, feel if the clutch is engaged. If you put your hand on the compressor, you should feel a vibration. If not, the clutch may not be engaged.
Furthermore, you should listen to the compressor as it runs. It should create a steady humming sound. When the clutch isn’t engaged, there may only be a clicking noise.
Additionally, look at the pulley. When the clutch is engaged, the pulley turns. If the pulley isn’t turning, the clutch isn’t engaging.
You can also jump the clutch if it’s unclear what the problem is by now. To do this, you want to follow these steps. However, you want to be sure of what you are doing and keep your hands away from any moving parts, or you may be seriously injured.
- Unplug the connectors to the compressor.
- Attach your jumper connectors to its electromagnet. A wire crimp tool will be necessary to attach to the small connectors.
- Link the car battery to these wires. One of them connects to the negative battery terminal, and the other goes to the positive side.
If the electromagnet is working, the compressor clutch is going to kick on normally. Free the clutch by removing the positive wires. You can perform this process a few times if you want to ensure everything remains operational, especially if you are dealing with sporadic issues. You should hear the sounds of engagement every time the clutch is activated.
Where Is The AC Compressor Clutch Located?
Because the clutch is part of the compressor, you can expect to find it on this vital air conditioning component. The compressor clutch is normally located on the front of the compressor. As you turn on the air conditioning system, the clutch should engage and start the compressor.
If you don’t know where the compressor is, you want to look toward the front of the engine. It’s a belt-driven accessory, making it easier to find. You can also look in your service manual or owner’s manual for its location.
What’s The Function Of The AC Compressor Clutch?
When you turn on the air conditioning system from the control panel of your vehicle, a signal is sent to the AC switch on the car. This switch permits power to travel from the engine to the compressor. The compressor’s job is to compress the Freon, so it can be used to cool the air. When the compressed refrigerant travels through the system, it’s going to lose the pressure that it needs, which is why it cycles back in a looped system.
The clutch has the important job of activating the compressor so that pressurization can occur. Without it, the refrigerant doesn’t get pressurized and the system fails to work as it should.
How Much Does An AC Compressor Clutch Replacement Cost?
To replace an air conditioning compressor clutch, it’s usually best to put in an entirely new compressor. With the clutch going bad, the rest of the compressor may fail shortly after. For the cost, it doesn’t make sense to mess around with the clutch.
To replace an AC compressor, you may spend $650 to $1,400. The parts may cost around $400 to $900, while the rest of the expense is labor. On average, it could take two to three hours to replace an AC compressor.
Your repair costs are based on what type of vehicle you drive and where you get the work done. Labor costs by state vary, with California having the highest average labor rate and Ohio coming in with the lowest. Even in the state alone, the region you live in makes a difference. You can visit a mechanic in a rural area and pay far less than you would in a busy urban environment.
Of course, the cheapest way to replace the AC compressor is to do the job yourself. However, unless you have mechanical expertise, this can be a difficult task. I’m not saying you need to be a professional like I am, but you will need to know how to work with the air conditioning system, and you will require some special tools.
To replace the AC compressor, you need the right AC tools to drain and fill the AC system, and in this case, it may be wise to let a professional do it with the right equipment to make a safe replacement.
Is it worth replacing the AC compressor clutch?
No. Few mechanics bother with replacing the AC compressor clutch anymore. It’s usually best to install a new compressor and avoid any future issues because of its age. You are going to spend much more, but it gives you peace of mind.
Can I drive my car with a bad AC compressor clutch?
You may be able to drive the car, but you probably should have it repaired sooner than later. If the clutch is seized up, it can cause damage to the serpentine belt or AC system. When the serpentine belt fails, the alternator and water pump both stop working, leading to more serious issues.
What causes a car AC compressor clutch to get burnt?
You may need to replace the AC relay or the AC pressure switches. These parts are responsible for supplying the necessary power to the clutch and the compressor. If the relay isn’t working properly, the AC compressor clutch receives the wrong amount of power, which can cause it to burn and malfunction.
How long does an AC compressor clutch last?
On average, the lifespan of a car air conditioning compressor is ten to twelve years. The clutch is a moving part that endures a lot of abuse. It could fail before the compressor would, but you will probably want to replace the whole unit instead of just the clutch.
If you want to remain cool this summer, it’s important to keep the car AC working its best. After all, you don’t want to arrive at work all sticky and sweaty. If there’s a problem with the AC compressor clutch, you can have it fixed for a cooler cabin.
Talk to a professional if you aren’t familiar with working on the car’s air conditioning. This is a sophisticated system, and it’s not meant to be tinkered with by novice mechanics.