Its impossible to see the inside of the connector on the compressor, but I got a wire to clip on to one of the metal prongs and grounded it, then I ran a wire from the battery to the other metal prong, and it definitely locks the clutch.

 

Have you checked the relay? It could be the computer is grounding it but that its not switching. Considering how much relays are I would just swap one in and see if that takes care of it. That would be quicker than checking every wire.

 

I've switched the relay with the horn, and the horn works both times.

 

Well the ground wire is hooked up good. Man I don't want to take this to the dealer, especially since I've pretty much checked everything.

 

I'd never take your truck to a dealer David, hell no.

If you did, make sure they can't open the cutout and put in a very very limited tune.

 

you can limit mph in the tune easy,

Does chase no anybody that can help ya?

 

I wouldn't take it to a dealer, they're just too expensive. But where is a good ac specialist shop?

 

If you want somewhere local, head over to that O'reillys I used to work at over there and ask to talk to Ben (the store manager, hes a cool younger guy) and tell him you're a friend of mine and ask if he knows of a good place that won't rip you off. There's tons of shops in that area, and that store does a lot of commercial business with plenty of them.

 

couple suggestions/questions
1 are you sure you had the a/c on engine running when you checked the pressure switch

2 have you checked pin 85 to see if its grounding when a/c is turned on(if you jumped 30&87 on your relay spot like you said you did and nothing happened most likely rules this part out)

3 and you said the ground is good, have you happened to check the ground wire off the comp connector, as in put multi meter probe in the ground wire slot of the connector clip, then the other probe to a good known ground or where that wire grounds to?(make sure theres no power present anywhere when checking resistance)

 

Does the engine have to be on during these tests? I've been doing them all with the key on and ac on max. I just put the multi meter on the pressure switch and it is indeed getting 12 volts.