I've been having a strange problem on my '04 max lately. If I start the truck with heat or defrosters on both driver and passenger zones, then switch to AC with the truck running the drivers zone goes to AC but the passenger zone keeps blowing heat. It changes to AC if I shut the truck off and turn it back on. http://www.dieselplace.com/forum/smileys/smiley5.gif I'm at 34k so I need to get it in for service but I hate to take it in because you know sure as sh** it won't do it for the dealer. http://www.dieselplace.com/forum/smileys/smiley7.gif Any ideas ???????? Edited by: BlueMaxxxx

Push auto for 5 secs

Auto ????

I saw you have an SLT.


I just assumed that you had the full AUTOmatic climate control system.


If I misunderstood and you have dual manual system. Then I'm at a loss.


Most of the time this problem is with the driver and passenger sides at different temps.


And the driver memory feature saves climate control information, both for the key fobs and the last adjustments made.


Am I off base?

I do have a SLT. So I got out the 2004 GMC brochure to look at the dash. WOW! The climate control system in the pictures is really different from mine. So I dug out my window sticker and of course the Dual zone AC is listed under the SLT Decor. I never before noticed that on the bottom of the sticker it says Air Cond., Dual Zone Manual -$195 ( replaces AC in package) I also have a -50 for a 3.73 rear axle. I never noticed theese were credits before ! http://www.dieselplace.com/forum/smileys/smiley3.gif


I guess I'll call the dealer today and set an appointment for next week as I'm going to roll over 35k this weekend. Each time this has hapened I've been on the expressway with AC on My side and heat roasting the passenger and no way to shut the truck down and re-start it.


On edeit I see that the in the brochure it indicates only the manual system is available with the snow plow prep package which I do have. Edited by: BlueMaxxxx

Happened to mine in the first week of driving. They repleaced the slider controls and all is well for now.


Dealer told me it had to be happening to fix it, i drove off the lot and got about 2 miles before it started happening again. I finally got it to happen on the way home