2004 Tahoe AC goes to heat in both front and rear

[anubisani]

ok I just fixed mines today actually 5 mins ago I had only heat blowing out the defrost vents on driver side and mild cold air on driver side defrost vents . but my rear a/c was working fine. 1st thing to check is the blend door actuator on the passenger side make sure it is working , take it out and change the controls and see if the center piece moves , if it does remember the original position and use a plier and turn it back to where it was so you can get it back in . before you plug it back in remove 10 hvac fuse on driver side , remove 30amp fuse also . go under hood an remove the other 10 amp hvac fuse. put the actuator back plug it in put all fuses back then turn the truck on but do not start make sure a/c switches are off , you should here the doors moving around wait 3 minutes for this process then turn truck off then start and it should be blowing cold air . I just did this like 30 mins ago ,my a/c was stuck in defrost vents for 1.5 years after I had a dead battery and here in fl you need a/c . hope this works for you .