blend door issues

[h2100]

Hello all, I'm sure this has been addressed but I can't find it. My 2006 SLT with auto climate control wont blow from the upper vents. It's blowing the wanted air from the bottom by the feet. My dealership said, 'bring it by, it's either a few hundred or a few thousand dollar' blend door fix. I am getting a bit of air from the driver side middle vent by the radio.

Ideas on how I can fix it?

 

[h2100]

had to go the the dealer. it was a actuator. cost $300

 

[new2yukon]

I hope this will help someone:
Mine blew defrost only...nothing else....temp control worked but flow direction did not. Fixed it doing two things.

1. Pulled 2 hvac fuses as mentioned on this site. Removed actuator just above gas pedal area. Opened it up. Found a gear split radially. Removed it. Rotated it 180 degrees so split did not come in contact with mating gear. Found no electrical contacts on this type of actuator. Reassembled. Reinstalled in truck.

2. Put fuses in and did the relearn process. All works fine now.

Right by the actuator is a white half moon plastic piece. This rotates when actuator is active and changes the direction of air flow. U can move it by hand if necessary to buy time before fixing issue.

My problem I think was the split gear. Works great now.