2005 QX56 Zone Fan Issues

[jeff_jones7]

After a few minutes when I turn off my car the fans appear to change zones and make a lot of noise doing so. Maybe closing when car not running? I'm guessing the 'gears' are slipping and trying to adjust from defrost zone, to floor zone, or possibly just closing up.

It's not terrible as everything works fine, but is pretty annoying and people think something is really wrong if they're in the car. I assume it's something to do with the motorized parts under dash, but wondering if anyone has had the same issues.

 

[marctronixx]

is it a clacking type of noise or a "rubbing" noise?

this is a fairly common problem. happens on armadas/titans of those years as well.

could need a greasing or replacement. could be a stuck door.

a test/troubleshooting tip is to turn the fan on full blast. start at the defrost level and stay in each "zone" for about 15 seconds, changing into the next zone, waiting 15 seconds, and rinse repeat.

if you hear the sound, this test can help determine which zone the actuator is in an that couldbe causing issues....

 

[jeff_jones7]

Yes, clacking sound for sure. Sounds like the 'gears' are grinding...yes, sounds like a stuck door.

Thanks, this is very helpful. I'm thinking about taking it in to get a lot of work done on it. I'll have them look at that also.

 

[QX56]

I put up with that sound of gears not driving a door somewhere in the HVAC for about a year. One day it stopped and my system never changed. It still works in all modes to this day.

As a note, the reason I responded to this thread is because my blower quit this morning when I went out to melt the frost. I decided to cycle it through all the modes at lunch time and the blower started working normally again.

I have been dodging the bullet on this 2007 more time then I'd like, but it's still all good.

______________________________

 

[marctronixx]

that is an actual troubleshoot method the dealer will do to prevent opening up the dash (not a pretty site). sometimes these things get stuck and forcing a high stream of air as you sllloowwlly change venting modes from top to floor can sometimes fix things. its also a good idea to cycle through the modes randomly from time to time.

re: blower, could be the control board or the fan resistor circuit. this has been known to go faulty rather than the actual blower.

first signs of the resistor circuit are slower blower speeds until the air just barely comes out.

for the hvac control circuit board, the controls can not operate or cloud be glitchy. sometiems even dirt gets behind the panel and causes some isseus....