1997 Chevrolet Suburban • 175,000 miles

I am trying to get my 97 K1500 Suburban AC working. When I purchased the truck, I new that the AC did not work. The previous owner told me that the compressor locked up, so he changed to the shorter belt and moved on. Now that I've moved to FL, I need the AC. While changing out everything I found that the rear ac has been disconnected and the shared pressure hose obviously changed out. I bought all new parts (accumulator, compressor, condensor, low pressure switch, high pressure switch and orafice tube filter). I'm not gonna worry about the rear air, I'll just be happy to have the front ac working at this point. Now that I have everything installed on the truck, I vacuumed out the system and it holds. The problem that I'm having is that my dash light is not coming on and the compressor is not engaging. I checked and I have no power at the low pressure switch. Checked all fuses and relays, everything is good. I'm not sure where to go next. I've read several things about checking the control head in the dash, which I may try next. This may also be relavent, the 1st and 3rd settings don't work on my fan settings.
July 28, 2012.

The low pressure will go up while your charging thats normal. If the pressure is skewed or incorrect with a full charge you have other problems.

Jul 29, 2012.