I have been having some issues w/ my A/C. Basically, it would only cool for a few minutes then blow warm air. Even when it was cooling, it wasn't very cold. It turns out that when I hooked up my TST and FASS, both had a ground wire that you are supposed to connect the the negative battery cable. Somehow when you have both of these connected like that, it makes the A/C crap out!! How in the heck does that happen?? I shelled out almost $500.00 trying to get this fixed and the dealer couldn't make it right. The next step was ripping the whole dash out which would have cost a minimum of $500.00 more. A couple members here mentioned this and one referred me to the TST FAQ page where apparently this is a widespread problem. It seems the FASS or Airdog are two pumps that will help cause this problem. To solve this issue you just hook the TST ground up under the dash.
Anyways, my A/C blows super cold now and I am extremely happy. I was even toying with the idea of pulling some mods and trading in on an 06... Now I can keep my 03 Super Output for years to come......
The funny thing was how they would call me and tell me my truck was done and the A/C blows really cold.(3 times) I would pick it up and get 10 minutes down the road and it would blow warm again. None of us could figure it out. Well, what was happening was that I was turning the TST off when I dropped it off, so it worked fine, then I would turn it on as soon as I got in the truck after picking it up. I swear I never would have figured this out if not for someone telling me this.....

 

Ground the TST to another location...there have been a bunch of posts about this...a while back.

Funny how it does not bother all trucks.

 

I swear I don't remember ever reading about this!! I moved it and all is well now...

 

Well I didn't have a FASS installed and my air conditioner wouldn't work with the ground anywhere!!! On dash,battery, fender, frame, steering colum, or engine block. Worked fine with the box bypassed, but was slow as phuq! And was awsome to drive with the box on 5/4 with out the air. I just couldn't have the best of both worlds.

 

Well, I don't think I would get rid of the TST just because of the A/C issue. If I couldn't resolve the problem then I would have just turned it off when I needed A/C. That TST is just

 

I just had the Turbo timer added to my older unit. Now when it goes into cooldown the a/c compressor turns on by itself without running the fan.

The grounds of the TST and the Fass are at the same place at the battery terminal. I'll try moving it tonight.