All the air conditioning systems in automobiles have compressor clutches. These are generally electro-mechanical or electromagnetic, which means they are operated by electricity, but they facilitate mechanical force to transfer the torque.
Now, if you know little about mechanical parts, they tend to show issues from time to time. The AC clutch is not an exception in that regard. One of the common issues regarding this clutch is that it stays engaged all the time.
And, it would be normal to wonder why is your AC compressor clutch always engaged when you come across the issue. But the good news is that you came to the right place to know all about the problem!
So, let’s start giving you all the required information without wasting any more of your time!
What Does It Mean When Your AC Compressor Clutch Is Engaged All the Time?
The AC compressor staying engaged all the time is a symptom of an issue in your automobile. Generally, it means that the refrigerant inside your vehicle is always freezing. And when that happens, you will not be capable of getting a comfortable environment inside the car with the AC on.
How Does the AC Clutch Work?
To get to the bottom of the topic, you need to know how the AC clutch work. So, let us give you a brief idea about that first!
Basically, the air conditioning compressors operate by cycling through an on-and-off sequence. This sequence allows the compressors to maintain the desired temperature inside the cabin of the car.
The compressors will also rely on loads of different sensors. That includes evaporator temperature sensors, air temperature sensors, and low-pressure switches. Those measures and adjust the temperature or cooling level accordingly.
The clutches will control the cycling sequence of the compressor motor. That allows the compressors to offer optimum cooling performance. When the car’s electrical system determines that the AC compressor needs to cycle, it will send an electronic signal to the clutches.
After getting the signal, the clutch will actuate the small pump, which has the main task of pressuring the oil that is inside the piston. This pump operates by relying on an electric motor and always stays on when the car is running. A hydraulic thrust bearing will push against the crankshaft when the pressure is proper inside the piston.
That thrust bearing will force the crankshaft to go forward. And this motion will move the armature sets. And eventually, the AC compressor will activate and will open the contact switch, which can deactivate it.
AC Compressor Clutch vs Engine Clutch
When there are problems with the air conditioning compressor clutch, it will stay on even when your engine is off. That could seriously be a problem. But before you go ahead and try to diagnose and fix the issue, you need to know the difference between the engine clutch and the AC clutch.
The engine clutch basically disengages when the vehicle is off. However, the AC clutch can stay open to keep an adequate temperature. In other words, the AC and engine clutch are not the same.
Replacing the Thermostat or Wiring Harness
One of the first things people will advise to address and fix the issue is to install a manual override switch on the air conditioning system. That allows the driver to disengage the AC without needing to turn off the car.
However, you need to consider the fact that you will be replacing the original thermostat of your car with a new one. The override feature will be integrated with the design. But you must go through a couple of steps before placing the new wiring harness or thermostat. And they are:
- Turn the vehicle on with the AC compressor engaged and turn the vehicle off again. If the AC finishes the cooling process after a couple of minutes, then the thermostat is not the problem. There are other issues present.
- Start taking notes of the parts’ behavior when turning the vehicle on. Open the hood of the car and do a thorough check on the systems and components that the AC system is utilizing.
- Focus on the switches that powers the AC compressor, the AC relay monitors, and the auxiliary air pump relay. Also, check whether the coolant temperature sensor is working correctly or not.
What Do the Fans and Relay Do?
The fans on the air conditioning unit will move the air through the system. They will circulate the air from the intake to the outtake port. And the relays that are present in the system can change from one state to another.
They can be hot or cold. And the condition will depend on whether you have an appropriate amount of heat in your car or not.
What Causes the AC Compressor Clutch to Say All the Time?
There are a couple of things that can contribute to this problem. However, there are some simple repairs that you can do to assess each of those issues. Allow us to give you a better idea of what we are talking about here:
Over time, the thermostat can fail or break down. And when that happens, it will require a replacement.
Compressor Is Faulty
If the compressor is faulty, the compressor clutch will always stay engaged. And when you notice that the compressor is not working optimally, you should get it replaced.
The Air Conditioner Heater is Faulty
Sometimes, when there are problems with the compressor clutch, it indicates that there are issues with the AC heater. It might have failed, which is causing the air conditioning system to not work optimally. You can fix the entire issue by replacing the thermostat.
Blocked Tank Hoses or Drain Pan
If the drain pan has debris and water, the air conditioning system will not work effectively. You can easily fix this issue by getting the drain pan out and cleaning the debris and water.
However, if your tank contains a riser hose, you might face difficulties while cleaning it. In that case, change the riser hose and drain pan.
You would want to get your vehicle checked up by a professional if there are broken fuses. This is something you can not fix that easily.
If everything seems right and your air conditioning is not working optimally, it can be a defective unit. In such cases, first, get the AC checked up by a professional and see if any repairs or replacement of parts do the trick or not. If that does not work, you should replace the entire AC unit.
From this guide on AC compressor clutch always engaged, we hope that it is clear that the compressor clutch issues do not always call for an AC replacement. Sometimes, you can repair or replace certain parts to get the issue fixed. And now that you know that, you will not have to spend more than you have to!