rear a/c blows red hot

i have searched and read but can not find help for this one.
please read and help if possible

on my 2001 silhouette,
can someone tell me how to access the temperature actuator door for
the rear vents.

my kids have been whining for the longest time saying the air was no good in the back, i waved them off until i went back there the other day.
sure enough, its blowing red hot air. when it is set to a/c

i spent an hour checking manual and made sure i wasnt doing something dumb with the controls.

i am pretty sure its the actuator door since,
when i run the fan with the motor off, (key on) i get ambient air temp,
but if i start the motor i get heated air. (meanwhile the front is blowing cooled a/c air) sooo, i suspect that when the car starts the vacuum closes off the door to the outside air and hence i get heated air, but the door is for some reason not listening to the controls and moving it to cool.

cant be the controls, since there is two sets (front or back) that can possibly control this and neither can make it cool.

i checked all fuses, but strange enough, in the manual, there is a fuse for the temprature door actuator (front) but none that says (rear)

could just be a fuse but where?, dont know where to begin looking for the door either
after reading a bit hear i guess i am showing how long it has been since i used to work on cars. I guess the door is not controlled by vacuum anymore? SERVOS? what is that a little robot lingo?

thanks in advance for me and the kids, its getting hot again

The hard part is getting the rear trim panel off (that covers the whole AC/heater in the back).
Here are the instructions:

1. Remove the rear seats.
2. Remove the back body pillar trim.
3. Remove the body side upper trim panel.
4. Remove the cup holder from the rear quarter trim.
5. Remove the rear accessory panel from the left side quarter panel.
6. Remove the retainer bolt from the seat belt retractor.
7. Remove the upper cargo net retainers.
8. Remove the liftgate sill plate.
9. Using a trim tool, remove the rear quarter trim panel retainers.
10. Remove the rear quarter trim panel from the vehicle.

Once you have the covers off, the rest is easy.

I hope this helps.

Take Care,

wow, great info,
took apart as described above
and found the "servo" that controls the temperature door.
after taking it out and examining i found the servo works fine
but the connector is crummy and looses contact
tried a few things to fix but nothing seems to do the trick
i ended up siliconing a piece of styrofoam to the inside of the
interior panel to hold pressure onthe plug
and hopefully keeping into operating.

so far so good,
thanks for replying Greg