The difference between a reg compressor and and a variable displacement compressor is, the regular one may cycle(on/off) when activated, while the other won't(it remains on until the system is turned off)......

Only way the compressor stays running is a bad control head or a short to ground in the control circuit.....

So, if you unplug it will it turn off?

The compressor uses a PMW solenoid to control pressure that is applied to a wobble plate that increases or decreases the piston travel which is directly related to it'* volume of displacement. It'* always running but with it unplugged it is at it'* lowest volume.

Okay cool that makes sense. Worth a shot from what I can tell, even just as a diagnostic step.

Looking at a picture of it, it looks like if someone wanted to they could take out the three torx screws and the nut on the center shaft and remove what used to be the clutch assembly. That might diagnose it a little further.

Disclaimer: I've never done this on one of these. Do this at your own risk. Professional driver on a closed course. Results may vary. Etc.

Now that that'* over with: If it were mine I'd probably try that to diagnose further. Either way, it sounds like it is a compressor replacement regardless.

Oh yeah, the picture:

OP is not answering us....yes, if the clutch is engaged with the A/C system off, then pull the plug on the clutch....if it stops we have a bad control head or a grounded control circuit....

If it stays engaged, then the gap may be too small and something has got in there and wedged the clutch to the pulley.....

It'* a variable displacement compressor. They DO NOT have a clutch.

They most certainly do.........

What a variable displacement compressor does, is change the stroke according to load on the system.....thus, when the clutch is engaged, it runs continuously....it doesn't cycle on/off like the CCOT compressors...

They do have a built in limited slip clutch to allow for the pulley to break free in case of an internal failure to keep from losing the drive belt. These clutches are always working and do not use any electrical connection. Most of the time they are just an area of rubber that will shear off when the shaft jams.