My a/c clutch is not engaging and I'm not sure what to look for. A/C just blows hot air. Blend door seems to be functioning properly. I haven't had a chance to have the system pressure tested yet. I tried to connect a recharge can to the low pressure port, but it didn't 'feel' like anything was flowing in.

Low side pressure switch shows 12.0V
High side pressure switch shows 12.0V
bypassing these switches has no effect.

A/C relay shows 0.1 Ω on 200k setting between the outer two blades.
A/C relay socket shows 12.0V between the same spades.
12V to outer blades causes relay to click.

All fuses test good.
Compressor shows 0.0 Ω at plug receptacle.
Compressor plug shows voltage between 5 and 7.5V.
Clutch will engage when jumpered to the battery.
I've removed the .040" shim from the clutch bolt, thinking the coil was weak. No difference.

Is there anything else I can check in the meantime?

 

bump

 

2001 AC wiring diagram below

The computer(PCM) activates the AC relay that sends 12v to the Compressors clutch.

It does this by passing on the GROUND it gets from the Pressure switches, so not sure why you were reads 12v at the pressure switches?
But if you jumpered them and they were Grounded at the end then it should be a good bypass test

But I would test OHM to ground thru those switches, maybe Black/white stripe Ground wire was broken or disconnected

EDIT:
I see you have a 2001 2.5l Lima not the 2.3l duratec
So the 1998 AC wiring would be closer to what you have, but basically the same method to activate the AC compressor

 

Thanks Ron. Answers added to quote.

 

I'm not that experienced with the electrical aspect of these. But the 1st thing I'd do is make sure the physical pressures are where they ought to be before I'd chase down electrical. Low side ought to be around 35-45 and high side ought to be >150psi