can anyone tell me what might be going on with my ac. I have a 2006 dodge 2500 ram diesel. The ac compressor cycles on and off about thre times then shuts off.

 

You probably have a leak. The compressor is starting then the computer is looking for pressure. If it doesn't see what it is looking for, it shuts the compressor off. The best thing to do is bring it to someone who can inject a dye in the system and look for where the leak is.

 

no leaks that I know of. Pressures are good on both high an low side (between 30-40 low side and just over 200 high side). Read something about dodge having problems with an ac power module. Seems to me that it is either the pressure switch (i can only find one on the high side line) or the dash board switch.
Any other advice would be great.

 

use a volt meter to check before and after the pressure switch to see if its the culprit, if not wour your way back through the system, there should also be a deicing switch near the evaperator that can cause issues

 

thanks dodge trucker but ...huh? Where do I check? Do I leave the pressure switch connected and pierce the wires or disconnect them and check the plug? If the plug is what I check there are three pins. Which ones do I check.
I do not see any other switches in the system at all. The harness is loomed together with wiring that goes to the turbo housing andwhat looks like a relay on the housung but I'm sure they are not related.
Thanks for the suggestion and I will do my best to figure out the voltage.
Do you know if that switch has a schrader valve behind it?

 

sorry bout that, i was thinking tractors for some reason, the 3 wire switches do both high and low cutout, there should be a shrader behind it, but i cant remember what the voltage readings are for those switches, the best i could tell ya is to replace it and see what happens, maby you could find a nother vehical to swap it out with, to test before buying

 

Are you sure the compressor is cycling? The reason I ask is I had a bad coil on my compressor that was not engaging the compressor, but the idle still bumped a little bit every so often like it was still engaging. Visually confirm that the compressor is in fact engaging before you go any deeper.

 

yes...compressor cycles and even runs like nothing is wrong at times. Cools great until I shut the truck off or ac off then the fun starts all over again.
Can anyone tell me how to test the pressure switch? It is a three wire switch. I think that there is some sort of problem with that switch but since it is around 100 bucks I don't just want to swap it out and see.

 

not the switch!!!! Just bit the bullet and bought the switch. It took about 30 seconds to change out and still does the same thing.
If anyone has any more ideas I would sure appreciate it.