No A/C

[TanK203]

Hey everyone! So I've been suffering this summer with the EvoBeast not having any AC. The compressor was swapped out in November because of a rattling sound coming from the engine bay and of course never noticed it wasn't working since it was too cold to need it. However when the warmer weather started I realized I had no AC. I brought it back to the shop and they determined the compressor was bad (clutch would not engage). They swapped it out again with a motorcraft compressor and it bench tested OK, however the clutch will still not engage when the computer calls for it to.
The shop had it for a few days and really have no idea why it's not engaging, they suspect a wiring issue (wiring harness was replaced when I bought the car two years ago because some wires melted and shorted. Just curious if anyone has any tricks I can try before I bring it over to an actual Ford dealership to have them look at it. Appreciate any and all help.

2013 Sho w/ PP

 

[Johnbigdog]

If they cannot active comand the compressor on, there is an input preventing it from operating it, or there is a circuit fault present. (high resistance on a circuit or poor pinfit)

They can provide ground to the A/c compressor realy control circuit at the pcm to see if the clutch engages. That will be the fastest way to isolate an input vs a circuit/output fault regardless of a bench test. No dtcs doesnt mean there is not a circuit fault.

Inputs to look at:
Refrigerant static pressures ok compared to gauge set
Engine not overheating (engine coolant temp)
Ambient air temp reading above 32 f. (After a cold soak)
Evap temp sensor reading above 33.8 f. (After a cold soak)
No pcm dtcs present.

 

[stripSHO]

I’d start with the basics, like is there refrigerant in it? Are the pressure switches closed? Does the relay work?