Blown a/c clutch fuse

[aber4]

Hello all, I have an 08 Monaco with the Cummins 6.7 engine. We bought the unit new but it was two years old and the AC doesn't work. The AC clutch fuse (20amp) blows out when you turn on the AC. I checked the wiring from the fuse panel to the ac compressor and it isn't grounded (shorted). I checked the connection to the compressor and it is fine. I tried a 25 amp fuse and it blew also (I know that's a bad idea I was just doing it for trouble shooting purposes). Any one have any ideas or dealt with this already?

Many thanks,
Mike.

[bigskymt]

I would unplug the wiring harness from the compressor and turn on A/C, thus eliminating the clutch. The 12vdc powering the compressor clutch magnet may also power the condensor fan. If that power goes through a pressure switch there's another potential problem.
You may consider running a dedicated fused 12vdc+ line to the compressor for testing purposes.

[Phobos]

Try what bigskymt stated, that's a good test. I have a feeling though, that the compressor clutch coil is shorted and that is what's blowing the fuse.