Heat/AC problem, won't change to different outlets

[glock35ipsc]

We have my brother's "new" 2000 running great after replacing the fuel pump and filter, now we have a heat/AC problem. Now matter what position the selector is in (dash, defrost, floor, bi-level, etc) we are not getting air coming out of anywhere. There is a little that can be felt through the floor, but the bottom line is the doors are not moving. The blower will run through all the speeds just fine, but we just can't change the outlet position.

Are these vacuum controlled or electric? I can only guess electric since I can't find a vacuum hose going through the firewall anywhere under the hood.

A little background on this truck..... when the fuel pump went out, the P/O just towed it home and parked it, and it sat for about 1 year. I don't suspect that mice got in the interior, though I guess it's still a possibility. But there was no evidence of mice inside the truck, and there is no smell (you know that smell I'm talking about! ) coming from any of the vents when the fan is on high, nor is there any "mouse house" stuff coming out of any of the vents.

Anyone else had this problem, or know where to start?

Thanks in advance.

[PT'S 70 CST]

I know this sounds kinda crazy but these trucks, burbs and tahoe's had a bad problem with the temp control switch panel. Although this does not sound like it may be your problem the switch could be stuck in a floor selection mode or something. I may have a spare if yours looks like this.

[bulldoggraphics]

I have had the same problem there is a control servo just above the brake pedal if you notice the air will blow out of the dash then when the car primes up and the fuel pump relay turns off the air blows through the defrosters, that servo controls these vents you can pull the wire to make it stay in the dash until you have time (30min)or the money ($50) to buy the control head unit, but that will fix your a/c/ problem
Hope this helps

[glock35ipsc]

Thanks guys!

bullydog - By saying "control head unit", are you referring to the dash switch cluster like PT'S 70 CST posted?