What causes power windows, locks, radio and a/c fan to stopped all at once?

SOURCE: 2004 tahoe

make sure than you have not split any fluids on the passenger front door most of the times is where the module to control the windows and doors is located, try by unpluging the batterie and the after a minute plug it back and see what happend but if any of your ft doors have been split with liquid or rain has gone inside then most likelly the module got moisture and not working

SOURCE: gmc envoy remote key not working

Sounds like you need a new keyless entry box, but forst try resetting the computer, by taking the positive battery cable off for 10 mins.

If that does not work then seek geting the box for the keyless entry replaced.

SOURCE: 2000 Safari, power locks,Rear dutch door wont unlock,

can you use the key its self on the rear door. what i mean is not using the remote but actually using the key?

SOURCE: HAVE A 03 GMC SIERRA

I had the same problem in my wife's 2003 Yukon Denali. The power seats and passengers side window wouldn't work. Turned out to be a blown Buss Type fuse in the Underhood Fuse Block. It is the one marked MBEC 1 50amp. Hard to tell if the are blown so look very carefully. Should look like a hoop with two shiny solderlooking bubbles on either side. On my blown fuse, it caught my attention because it looked like the solder was missing and I had to look very closely to see the bottom of the "hoop" was open. They are very hard to remove and must be pulled straight up.
This type of fuse looks like a red square with a clear plastic top showing the fuse link under the plastic. On my vehicle it is on the top row second one from the left.

SOURCE: Power Door Lock Problem

The last post by maddog1321 was exactly what I had with my right rear door. The electric locks would not lock and unlock, and you almost couldn't do it manually without my feeling I was about to break something. I took the door panel off, oiled everything and got no relief. Finally, I saw the above post and drilled out the aft-most pop-rivet. THE WINDOW WORKED PERFECTLY! I didn't drill out the forward (closest to the handle) pop-rivet because I wanted to do one at a time so the solenoid would not fall out of place. I then put a new pop-rivet in place of the one I drilled out. I then reinstalled everything and the locks work like new.