No Power to ac compressor

[karashaw809]

We have a 2021 ace Thor and we have no power to the AC compressor. We are looking for schematics from the switches in the dash to the compressor. If anybody has any ideas I can provide that information.

 

[PS89]

I have the Ford factory schematics for the '20 F53. Should be the same for either a '20 or '21 F53 since you'll have one of those.

The difficulty level in diagnosing the cab A/C system is compounded by it being a hybridization/integration (I prefer to think of it as bastardization) of the Ford-supplied system with the system chosen and installed by the Thor factory. That system would need to be positively identified in order to get a complete picture.

Also, you really need a scan tool that can read PCM PIDs as the compressor clutch relay is controlled by the PCM. Forscan with a recommended adapter can do this.

A couple of things you can check immediately: Fuses F34 & F46 in the under-hood fuse box and check for continuity of the low pressure cycling switch. After that it does get more involved.