Edmunds Answers



  • karjunkie 10/03/08 12:12 pm PST

    Is your heat duct door stuck on heat? This door is usually vacuum operated. It can stick in place from hot temperatures in the interior during the summer. First make sure you don't just need to pry it open again because of sticking. If so, a little graphite lubricant may do the trick. If not, check the vacuum hose for leaks or tears and replace it.

  • yfrankiii 08/05/09 2:45 am PST

    My problem was the total opposite side...I think your side is easier to get to than mine, I think yours is on the passenger side, under glovebox, need to remove cover that is under the blower/HVAC unit, i am not 100% sure but believe it is right there on the bottom easily accessible, might want to try what I did but on that actuator. this is my original post, but remember this is for the drivers side blowing hot air. ...

    I have 2005 Chevy silverado, same as GMC Sierra with dual climate control. I was getting hot air on drivers side but Passenger side was cold. I was also getting air only out of the defrost vents. I had to change battery for other reasons but noticed after I disconnect batteries, (2 for diesel) the air now worked in the front vents.....odd...but perhaps just needed to reset position on door flap but that only lasted a litte while and again had same problems. Anyways, took to dealer, said I need left side temperature door actuator and recirculation actuator per their trouble codes, wanted $290 for each actuator, each is the same part number. and another $460 for labor, over a thousand dollars. Researched internet and found someone had removed actuator and open it up, cleaned grease off the contact and circuit board and it worked for them. I figured worth a shot. I removed the actuator on the drivers side, right behind and above the gas pedal. I removed the actuator by removing two screws bottom and top. There is a backing plate or actuator plate that is a large half circle shape with small geared edge and two channels cut out in upper edge. Remove plate with actuator. Mark the location of actuator in reference to the plate. with actuator removed and unplugged i started engine and turned on AC. Move the white gear that was attached to the gearing on actator plate manually and see if cold air now flows to vents on drivers side. Mine did. I took apart actuator with small flat screwdrive and small pick to open clips on all sides. nothing springs apart. just remember how gears fit together, I removed gears and used q-tips and some alcohol to clean off contacts and board, You will see a split contact on black piece that backing plate locks into. Clean contacts and the bands they rub on. with gears out, i checked with 9 volt battery with small aligator cips to see if motor spins, reverse polarity to test both ways. Before you pop the cover back on, make sure the actuator fits into the backig plate in the same position. I had to take mine apart again because I didnt have the geas lined up to be in same position for alignment with backing plate. I have to slip gears out and move the black gear on tooth over so it lined up the same as before taking apart. Mine worked so I reassembled and re installed. INstallation is a pain. found with engine running and ac blowing i could move white gear on HVAC unit towards the back of car or and since its blwing the vaccum holds it in that position, same as the small knob to the front on the that needs to be pushed up to move another flap inside the HVAC unit. With those in place, put actuator plate back up against HVAC unit, one curved slot for where screw goes into a small tower hole and knob that you pushed up goes into outmost channel slot and white gear matches up to geared area on plate, Be careful, on back of white gear there is small knob that needs to slip into channel slot on backing actuator plate then press plate flatly against the HVAC unit. You can then slip on actuator unit into the spot that you marked previously to line up with backing plate. Screw in screws. Shut off engine prior to hooking up wiring. then restart and hopfully like mine...that wil work for you too. saved me a $1000....


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