I previously had a problem where my A/C would blow hot on the drivers side only occasionally. I recently replaced both batteries and now I have no temperature control whatsoever. I start the truck up, throw on the A/C and it blows cold on the drivers side, and hot on the passenger side. After a few seconds it switches, to hot on driver, cold on passenger. Then my truck just says ***** it and blows Africa Heat outa both sides. I have unplugged the plugs from the passenger side access panel, pulled every fuse that has to do with HVAC, unplugged the control unit and waited 5 minutes to let it recalibrate, screwed with the battery terminals and everything. Ive done everything thats been suggested on this site except go to the stealer. Ive heard temp door actuator could be the problem, but would both go out at the same time? I dont have the scratch to pay the stealer $1000 to fix this, but riding in a fogged over sweat box in the rain is killin me. Any input is much apprecciated.

Are you getting any codes? Check, then is there any of them listed in the TSB in this thread:

http://www.dieselplace.com/forum/showthread.php?t=254111&highlight=HVAC

If you have one or more of them, print it off and take it to the dealer and get that TSB done. Also check if you are having any of the other problems listed there. This fixes a more than the just the ticking noise, some never even have that. I highly doubt both of your actuators are gone.

FYI the TSB is free, they will just charge you for the time to do it. s/b only half hour labor.

Its not ticking at all that I can hear. I will check for codes on my way home from work today. Like I said, it only got real bad after I changed the batteries.

Its not throwing any codes. On the drive home the driver side was blowin cold air and the passenger side was blowin hot. Thats the opposite of what it usually does and Im not upset actually feeling cold air for once. Where exactly is the driver side temp actuator? how bout the passenger side?

I was having the same problem. I took the truck out the other day on a cold morning and set the temp to about 80 then in the afternoon it got warm so I set the temp to 70 and would you believe it worked both drivers side and passenger side was blowing cold air and so far it been working OK.

I had the same thing happen three times on my '05 suburban - same symptom, it would work then it wouldn't, then it would...until I would get so sick of it and go to get it fixed. Every time it was the actuator door. By the third time, I didn't even wait for it to happen more than twice, just called the dealer. Lucky for me the first time was under warranty so the next two times were all tied back to the first time it went bad so GM took care of it each time.

I would suggest you have the dealer do it once if you plan to keep the truck, because it will happen again, and when it does it will be their problem the second time, not yours....