A/C clutch stays engaged

I will get one tomorrow and let you know the results.

Roy, before I get a command center let me say that the compressor clutch would stay engaged all the time. Even when the pressure should have made it turn off. I have replaced; compressor, dryer, expansion valve.

Yes sir, clutch stays on. Pressure is not cycling 35 low 150 and up on high.
Could this be a problem with the control center?

Okay, Let me start over, I have had my vehicle to shops. Not a whole lot was resolved. It appears I have a ground problem, that was the answer from the A/C shop. The electrical auto guy says it is a thermostatic meter. Let me just reiterate, I did find a wire crossed at pressure switch to make the compressor run 100% of the time (fixed) The compressor, pressure switch, expansion valve, dryer have all been replaced, system has been evacuated, flushed, but the pressure is running to high on the high side. The cycling time is not right.
My understanding is the signaling for it to go from high to low cycling is not right. Can someone tell me a common reason for this? Might add the relay has been checked and it shows that if you ground it the compressor kicks on when its not on. Maybe this is a clue.
Signed, in over his head.

Eighty degrees outside (Texas). Low 35 are so, high going up to 250.

Okay, So I took my vehicle to a couple of hack shops, The A/C shop told me I had a ground problem so he sent me to a auto electric shop. The guy at the electric shop tried to convince me to run a ground from the relay so the compressor would stay on (all the time), not knowing I knew better.
So he diverted to it is the thermostic reader on the EVAP. Nope I replaced that. Needless to say he charged $40.00 for what I already knew. A/C blows cold air but will not cycle properly. Help!

I have this exact issue haunting me right now. If you can name it, I have changed it. Compressor, condenser, evaporator, expansion valve, dryer, triple pressure switch, relays, thermal control amp, control head and even swapped the ECU! Something on my car is telling something the A/C should be running. I even get both fans running too! I have spent hours and hours pouring over wiring diagrams trying to find out where this thing is getting a ground to close the AC relay. I have shot all wires in this system to the ECU and I have nothing grounding out. I have a work around in mind. It is a thirty degree old school mechanical switch stuffed onto the EVAP core, a relay and a master kill switch for winter use. GLYN, if you get any further along, please post it here. My air is nice and cold, has the right amount of PAG and refrigerant, but when the car starts, I can hear the clutch engaging with the system turned off. Very weird!

That is the first good idea I have heard yet! I will remove that signal wire from the ECU from the relay tomorrow and report back my findings. If this shuts off the compressor, then we at least know which direction to look. Thank you.

Ken, I removed the signal wire running from the relay back to the ECU. Compressor clutch disengaged and both rad fans stopped running. I was talking with the guy at O'reillys. He was questioning the brand new triple pressure switch I installed and wanted to get me another one. Sure, he is not the one that has to reclaim, vacuum and recharge 134a. :-/
Back into the wiring diagrams I go.

I will do you one better Ken. I swapped out the complete control head with another today and same deal. I am really starting to give the new pressure switch the stink eye. I have a spare stock Nissan one and I am going to try that next. Seems to me right after I rebuilt the entire AC system, I had rapid clutch cycling. So it was then I bought a new pressure switch and that was when I discovered I could never shut the silly thing off. O'Reillys said I probably got a faulty switch from them. Needless to say, I am not going to try another new one. Who knows, maybe the new ones are not wired correctly? And I have no desire to figure it out either. Lol