Mode Door install 2000 GMC

[RonnieT]

 A brief history first.

     I have owned this 2000 GMC 3 door 5.3Lt.  for about 15 years now, when I got it , the heater never worked well, but I changed the cabin filters a few times, the heater core, the thermostat and coolant , water pumps, belts etc.

 It would never blow hot air on my feet.

About 6 months ago during the start of the winter, I decided to change to mode door actuator , with a Dorman unit 604-113.

 The one that is above the drivers right leg.

 I had pure hell trying to twist my way in there and get it all aligned up  to install. I did it several times but always failed with the correct way the  dial on the dash said it should be blowing , but finally did get it installed.

 about a week later my "blend door " actuator quit working and stated  popping sounds when going from cold to hot on the dial. that was OK because it was stuck on hot.

 Now that it is summer  I bought a new Blend door actuator and installed it, no problem there.

 but I then noticed  that the mode door was not working as every place on the dial only blows out the defroster vent.

 I pulled the panel off under the steering column and looked at the Mode actuator as I turned the dial and the gears or the "wheel" on the actuator is not moving at all.

  Checked the fuses and all are good.

Did I do something wrong while installing the Blend door actuator? or did the Mode door just fail?

 The Dorman I bought had the "wheel" built on the actuator.

 Is there a video or something that would help me in getting the Mode door actuator off and back on correctly the first time? how to align the  2 doors on the wheel and the teeth on the other door.

 My heater control is the 3 knob type with no driver or passenger separations.
Ron

 

 

[RonnieT]

OK Update on the blend door I installed yesterday, this morning when I started the vehicle, I heard a loud popping and grinding coming from the blend door actuator I installed yesterday, I quickly turned off the ignition and  reached down and unplugged the  wiring to the actuator , maybe I didn't kill it.

   Although after installing yesterday, I dove it several miles and I listed to it turning when I moved the dial each time and nothing unusual  until this morning. When i installed it I turned the blend door with my fingers to the position that was on the actuator whish was straight across left to right.  then bolted it  up and installed the wire, turned the key on and the blower and moved the middle knob from cold to middle then to hot and back and it moved each time.

   So is the Mode door actuator that is not working now throwing a signal to the blend door?