rear hvac on hot only!!!

[Tofer76]

ive been reading threads about the rear hvac on the ext/xl versions and what i have come up with is that my temp door actuator is shot.

i have heat in the rear only no cold air at all.
i have had no clicking at all from the rear.

i found the actuators on ebay for 55 bucks
Dorman 604 130 A C Heater Blend Door Lever | eBay

im wondering what the opinoins are of the experts here on my problem

any questions??

 

[RayVoy]

I think you have the right answer.

How is the AC in the front?

 

[Tofer76]

Cold as ice

 

[Mooseman]

You could try recalibrating the HVAC system by pulling the fuses first. It is important to not touch the system for the first few minutes after starting the truck.

 

[Tofer76]

Ok so what is the exact order of procedure to follow?
Key off/on?
Fuse#? First?
I dont want to mess it up by doing it out of sequence if there is one

 

[rkw]

In my truck there are 4 HVAC fuses under the driver side rear seat. The one that you pull to reset the A/C doors is "HVAC B". Don't remember the number.

Check to see if the mode actuator is working using the rear control. You should be able to get air to come out of the top vents, the floor vent and both. If not, that actuator may have problems as well. Check the " HVAC 1" fuse as well as I read that may have something to do with the actuators.

To reset: pull the HVAC B fuse for a minute and reinstall. Turn the key to on and listen as the actuators move the doors, first in front and then the rear. Do not touch any HVAC controls for a couple of minutes while the system resets. Any clicking noise you hear during the reset may be the sign of a bad actuator or broken door. I don't think it matters what you have the rear blower set to for this.

I used AC Delco #15-72811/GM #88892975 for my actuators $37.37 each from amazon. Good luck.

 

[Tofer76]

so does this indicate a future problem with actuators that i need to watch or could it be just a brain fart in the system thats no big deal?
do i need to go ahead and get actuators coming ?


1 pull hvac fuse b
2 wait a bit and then reinstall
3 start truck
4 wait a min
5 try to change rear air temp

right?

 

[Mooseman]

For 4, I'd wait a few minutes to be sure the recalibration is done. Be sure to listen for clicking.

 

[Tofer76]

Ok it worked! I can change the air temp now. Never did hear any clicking at all from the panel? Anyway is this goi gto just get worse till it wont work at all and a actuator needs repla ed or is it just a hit and miss thing?