I have has this issue for awhile. My AC compressor is cycling on and off even though the AC and recirculate buttons are off in the cab. I am running LS1 fans with a Nelson tuned PCM and fan harness, so one fan is coming on high when the AC compressor clicks on. I can't help but think that this isn't good for my gas mileage. I rarely use the AC. I am not sure if this was an issue before the efans or Nelson tune. Model and other mods are in sig.

Thoughts? Thanks!

 

I have also noticed that my low-speed fans rarely come on. In fact, I have NEVER seen them on in the two years I've had the LS1 fans and Nelson tune. There have been a couple instances in heavy traffic on a hot day where the truck started to overheat, so I turned the AC on to get the single high fan to come on and bring down the temps. Perhaps these two issues are linked?

 

I have read here that on certain years, the ac compressor will cycle while the climate control is in the hot position. You can more than likely change this in the tune.

 

You could also go to the 2 pin harness which is not spliced into the AC compressor.

Check your relays and wiring though. I had one relay get corroded after only a couple of months and I almost overheated.

 

It will also come on if your defrost is on.

 

That makes absolutely no sense. Why would they do that?

I will check the relays too, clearly the high speed one is working.

 

I think it pulls moisture out of the air....just like in the defrost mode.

 

As terravast4 mentioned, they did it to condition the cabin and remove moisture in the air, many different manufacturers do this. I agree that it's unnecessary for many folks, especially performance enthusiasts, but the normal Joe like breathing clean dry air I suppose

 

Ok... so the AC compressor cycles on when the AC and/or recirculate button is on, the vent **** is turned to partial or full defrost, or the temp **** is full hot? Does this sound correct? Does it come on at any other times? Thanks!

 

Did you cross check to see if it may not be the other way around. Anytime a fan cycles it in turn may be engaging the compressor? With the climate control system set to off.