Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum banner

What’s going on with my heater vent system??

982 views 2 replies 2 participants last post by  rogerth 
#1 · (Edited)
When my heater blower is on I can hear a change in the bower sound “speeds up or slows down”. Also hear a vacuums sound like the vents are closing / opening.

Ideas for what to look for?

Thanks

Vehicle 2002 Trailblazer LS too many miles

Update: Looked into this more. When I switch controls for defrost to floor heater I can hear the vent door activating and blower sound changing. It takes 1 min. to 1 1/2 min. to make the mechanical sound. So I'm thinking its a vent door control concern?

Thanks in advance for any comments on this.

Update 11/24/15: Thinking it is the resistor pack that could be the problem here? I did replace it once already long time ago but I had a couple of fan speed setting not working. My fan speed settings is working fine.
Can anyone tell me if it’s a symptom of a resistor pack going bad?
 
#3 ·
fixed

Thanks for the reply on looking at the HVAC actuator.

I had time to look at this again. Yes there was heat from all vents when controls were changed. Now the system is not making noise and is working.

The noise might have been from sitting for 3 months with out being driven. Good news is it working fine now.

I really like my 02 trailblazer.

thanks
:)
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top