Chevrolet Forum - Chevy Enthusiasts Forums - 05 Silverado Drivers Side Heater Problem

at any rate, this is what i did. (you'll probably need 7mm & 5.5 mm or the closest standard equivalent, tiny slotted screwdriver, large slotted screw driver for prying, some configuration of extensions, swivels, adapters. i took the black plastic kick plate off from under the dash. i think i had to use a swivel at one point and a 3/8 drive w/ 1/4" adapter because the extension for the 1/4" drive was too long. when you get it removed, you can see the blower motor (bosch) on the far right of the passenger side and its resistor (mine needed replaced because the fan only worked on "5"). You might also have to remove the duct work extension to the passenger side, but it just slides off.

the blend door actuator for the driver side is located just above the corner of the tranny hump on the passenger side. it is mounted to the bottom of the shiny black duct work. you should be able to see the black and red wires on the pigtail that plugs into it. it also has a red clip holding the pigtail in place. <O:p></O:p>
<O:p></O:p>
the blend door actuator for the passenger side is mounted on top of the duct work directly above the driver's blend door actuator. access to it requires the removal of the glove compartment panel and possibly other dash panels. <O:p></O:p>
<O:p></O:p>
the mode door actuator is located on the drivers side way up in the dash above the corner of tranny hump. is it mounted on it's side. This is probably not your problem if you trouble is similar to mine, but it's good for reference.<O:p></O:p>
<O:p></O:p>
At this point, hopefully you are in a quiet place. i put the truck in accessory, turned the fan off and moved the passenger temp control from hot to cold or vice versa. you should be able to hear the actuator motor spinning. listen closely, it's hard to hear. try the driver's side actuator. mine didn't make any noise so i removed the driver's side actuator by unplugging the pigtail, removing the the two mounting screws (gold, 5.5mm), and wiggling it back and forth. the actuator has a hole through the middle of it, connected to a gear inside, that sits on a post. basically, several plastic gears turn inside it, and rotate the hole which has two flat spots to grip the post. the hole moves the post which is connected to the bottom part of the blend door. When you remove the actuator, you will be able to turn the post by hand, and you should hear the blend door moving inside the duct work. If you can’t it is stuck and you need to try and free it up. I then used a small slotted screw driver to pry open the actuator. Everything in mine looked good. The gears weren’t stripped and nothing looked burnt. I pulled one of the plastic gears out (the one contacting the black one that turns the “hole” ). I repositioned the black gear a little bit. You’ll notice is has two contacts that slide along a circuit board. (Circuit boards are like magic to me.) To me, it looked like possibly those contacts slid off the board. With cover off, I used two small wires and the truck battery to test the actuator. Mine was spinning freely. I decided to hook the actuator back up and see what happened. You may have to reposition the black gear to get the hole and the post to line up. If your actuator isn’t working or you don’t feel like messing with it, a new actuator is about $155. Once I determined that actuator seemed to be functioning ok when I moved the temp control, I decided I would leave the kick panel off for now. If it quit working again, as a cheap fix, I would take the actuator off again and turn the blend door by hand to hot for the winter. When you think about it, there’re an awful lot of moving parts, switches, circuit boards and a motor to open and close one stupid little door. <O:p></O:p>
<O:p> </O:p>
Hopefully I helped you more than confused you. I promise it’ll make much more sense when you’re looking at it. Sorry for the lengthy explanation. I know a lot of my terminology especially with the actuator probably isn’t what these parts are technically called, but I’m not really a car guy, I was just cold. let me know if you have any questions or need a picture of something. good luck.