2015 gmc sierra ac not turning fans on

[Adoomie Abdallah]

Was having ac issues

Replaced compressor (new gm genuine)

Found leaks in 2 o rings, I replaced all o rings

Vacuumed and found no more leaks

Charged system and all is well with compressor 

Only issue is the fans will not turn on when I turn on the ac.

I tested the fans on all speeds using my autel scanner (dealer grade scanner)

And both fans work perfect.

 

Also found corrosion on the back plug connector (not the plug nearer to the top that you can see) to the ac pump, so I stripped the wires and soldered them directly to ac compressor. Not sure what that plug is used for so not sure if a bad connection may be the issue but I'm certain the connection is good. 

 

 

Assuming connections and everything else is fine, what steps would I take to find out why the fans won't spin with ac on?

[silveradosid]

the fans are controlled by the a/c pressure sensor here is the wiring diagram

air conditioning compressor.pdf