NEED HELP 04' Trailblazer EXT LS -How to install a Front Blend Door & Actuator.


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I'm a new member to this site and trying to learn how to use it. I was a Packaging Systems Designer & Engineer for 27 yrs (and a field service tech the first 4 yrs), however, I had a TBI (Traumatic Brain Injury) 4 yrs ago and I still have trouble at times trying to interpret and/or follow directions, (sorry). My Issue is: I'm trying to install a new Front Blend Door Actuator. Was only getting air flow from the Bottom only. However, I don't know the home position and/or what position the Vent Door should be in when installing New Actuator. The New Actuator has the 3 markings i.e. looking at it like a clock with the middle mark being 12:00 and Left Mark 11:00 and Right Mark being 1:00. It came in with the slot on the shaft at approx 2:00. I would think that the markings are relative to Vent Door position. My question is this; if the Actuator is at the 2:00 position, when I install it, what position should the Vent Door be in? Dash Air? Floor Air? Any and all help would be Greatly Appreciated...


It doesn't matter. Just install it at the position the new actuator is at. You might have to put it in and then turn it to line up the screw holes.

Reset the system. It will learn the new positions.
1. Pull the HVAC-B fuse for 30 seconds and put it back in (under seat fuse box)
2. Turn the key to RUN but don't start the engine. You will hear the actuators move around for a couple of minutes. Do not touch any of the controls during this time.

That's it.

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