Bad A/C clutch or something more?

[cheesepuffs2]

The A/C in my Accord stopped working one day, just overnight. It only blows lukewarm air now. Now, the pulley on the A/C compressor spins freely at all times with the serpentine belt, but the inner portion inside the pulley does not spin with the A/C on nor does it spin even if you try to spin it yourself with the car shut off. This means the compressor clutch has failed, correct?

The thing is I also hooked up an A/C pressure gauge to the system and it reads very high, outside the normal desired pressure range. My concern is, if the clutch wasn't actually allowing the compressor to function (hence the lack of cold air through the vents) then why would my pressure read high? Shouldn't it read very low?

 

[oggb]

May want to check the fuse and relay for the A/C compressor before going after the clutch.

On most vehicles the pressure on the high side and low side of the compressor equalizes when the compressor is off which brings the pressure up on the low side/down on the high side.

 

[JMJNet]

You did not mention a year. So I am assuming this is not a new car.
IME, just replace it. If the pulley is free spin condition, the compressor is gone.
Replacing the clutch only is usually more expensive, at least again based on my experience.

 

[Chris142]

If you can't spin the hub by hand that means that the compressor has locked up. Major ac repairs needed.

 

[Lubener]

Possibly a seized compressor if you cannot manually spin it by hand. Take it to a qualified shop for diagnosis.

 

[cheesepuffs2]

You did not mention a year. So I am assuming this is not a new car.
IME, just replace it. If the pulley is free spin condition, the compressor is gone.
Replacing the clutch only is usually more expensive, at least again based on my experience.

It's a 2008

 

[cheesepuffs2]

If you can't spin the hub by hand that means that the compressor has locked up. Major ac repairs needed.

Every video I see of a locked up compressor though shows it with the pulley unable to freely spin and then it creates a serpentine belt squealing, or worse, throws the belt. My pulley still spins along with the belt, just the center won't move.

 

[Lubener]

Every video I see of a locked up compressor though shows it with the pulley unable to freely spin and then it creates a serpentine belt squealing, or worse, throws the belt. My pulley still spins along with the belt, just the center won't move.

Yes, the pulley will still spin but the center portion is what is actually connected to the compressor. The center portion should be movable if your compressor is free. If your charge is gone or low enough, the clutch will not engage. You could be dealing with multiple issues with it.

 

[FowVay]

Try turning the A/C on and tap the pulley (use extreme caution) and see if the clutch magnet is just out of adjustment. Sometimes a tap will make things move a bit. If the compressor engages this way then you have a worn electro-magnetic clutch and it needs to be shimmed to bring it back into adjustment.

The fact that it ran fine last night and now just won't engage makes it seem like it may be something simple. As mentioned above, check the fuses and relays. There are also pressure sensors in the circuit what will prevent the compressor from engaging if the refrigerant is low.

And lastly, if A/C work is completely foreign to you then it might just be simpler to get a professional diagnosis to point you in the right direction. A/C work requires specific tools and tad bit of knowledge to get desirable results.

 

[vwmaniaman]

Our daughters CR-V had no working clutch and system showed a full charge. Clutch on compressor would not engage. It was a problem with corroded ground connection on compressor clutch coil. Cleaned the ground connection and is still working great. Don't buy anything till you check that ground.

 

[Chris142]

The pressure in the system with the ac off will be near ambient temp.90f=90psi. Add in underhood temp and the pressure can be much higher. The inner hub is connected directly to the compressors crankshaft. If that won't spin the compressor is locked up.

 

[mattd]

If you can’t spin the clutch the compressor is locked up. You should be able to spin it by hand

 

[Aichiguy]

Relays are often the issue.

 

[Chris142]

Every video I see of a locked up compressor though shows it with the pulley unable to freely spin and then it creates a serpentine belt squealing, or worse, throws the belt. My pulley still spins along with the belt, just the center won't move.

That is a locked up pulley. If you can't spin the inner hub it is broke.