Mircophones in roof of Denali making a Humming noise

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

delmaracer

TYF Newbie
Joined
Jan 24, 2023
Posts
4
Reaction score
0
They're not microphones, they're small fans that have something to do with the climate control system.
My 2005 has a very similar noise from the round thingy over & to the left side of the drivers head. It kinda sounds like a small fan to me. But how do ya get access to that item? Is there some schematic for it?
 

MassHoe04

Full Access Member
Joined
Nov 4, 2021
Posts
1,586
Reaction score
2,798
Location
Western MA
My 2005 has a very similar noise from the round thingy over & to the left side of the drivers head. It kinda sounds like a small fan to me. But how do ya get access to that item? Is there some schematic for it?
I believe that pops out of the headliner if gently pried out. There are a couple of retention clips molded into the plastic holding in the headliner panel. The sensor should snap out of/into the the face plate.

I didn't watch, but here is a YouTube on it...

I have heard they can make that noise after sucking in dirt and dust over the years. I saw a post somewhere, where a can of compressed gas (a can of computer/electronics duster things) was used to blow some crud out to solve the issue.

Mine makes a slight buzz once in a while, but I have not found the urge to pay $50 for a new one. I live the the occasional noise.
 
Last edited:

Roilux

Supporting Member
Joined
May 15, 2022
Posts
65
Reaction score
196
Location
Burbank, CA
So does anybody have a tutorial for removing the REAR ceiling sensor?

Genuine GM Parts # 22834330 Cabin Air Temperature Sensor Aspirator

Here's how I accessed the rear aspirator. Use a panel clip removal tool to remove retainer clips in the headliner. (See last photo, 2nd tool from left is most useful) I don’t know if this method works on Suburban, ESV or XL’s rear aspirators. There’s a video earlier in this thread showing how to replace the front unit.

Let’s go!

Remove the upper plastic trim at the rear of the headliner by pulling straight down.

Remove both D pillar panels by pulling in and forward simultaneously.

Disconnect speaker wires. Set panels aside.

Remove the rear cargo light lens and then light housing by sliding it sideways and let it hang.

Remove both coat hooks by pulling and prying along the seam that joins each hook. Each hook is two pieces that when eventually pulled apart will release as an anchor and allow the headliner sides to drop. I used two small flat screwdrivers and gently worked around the seam perimeter. Refer to photos for expanded hooks.

Un-fasten the C pillar panels down to the seat belts by pulling in toward the center of the vehicle.

Use a bungee cord to keep them leaning toward each other as shown in photo.

Remove the grill from the aspirator with pry tool.

Remove the remaining two round retaining clips (circled in red) along at the rear and center of headliner with pry tool. The headliner should now drop easily at the rear.

Reach in through the rear being cautious not to bend the headliner too much thereby creasing it.

Unplug the old aspirator and plug in the new unit. Check for power.

Position the aspirator over the opening while another person attaches the grill from underneath. If going solo, you MIGHT be able to reattach the grill and hold the aspirator while accessing them from either side. If not, use a zip tie as shown in photo to hold the aspirator in place, secure grill and gently pull out zip tie. Take care to use center most grill holes to help orientate grill snapping into slots on aspirator. Remove zip tie, it’s the prudent thing to do!

Replace center clips in headliner and side hooks followed by the light assembly.

Push C panels back in place, reattach speaker wires, replace D panels and lastly upper plastic trim between the D panels.


Viola! Now celebrate this little victory with a frosty beverage.

Happy Trails!
 

Attachments

  • 2.jpg
    2.jpg
    243 KB · Views: 5
  • 4.jpg
    4.jpg
    176.3 KB · Views: 5
  • 3.jpg
    3.jpg
    866.9 KB · Views: 5
  • 5.jpg
    5.jpg
    890.8 KB · Views: 5
  • 6.jpg
    6.jpg
    209.9 KB · Views: 5

mattbta

Full Access Member
Joined
Jun 19, 2012
Posts
1,069
Reaction score
1,933
Location
Frisco, TX
Genuine GM Parts # 22834330 Cabin Air Temperature Sensor Aspirator

Here's how I accessed the rear aspirator. Use a panel clip removal tool to remove retainer clips in the headliner. (See last photo, 2nd tool from left is most useful) I don’t know if this method works on Suburban, ESV or XL’s rear aspirators. There’s a video earlier in this thread showing how to replace the front unit.

Let’s go!

Remove the upper plastic trim at the rear of the headliner by pulling straight down.

Remove both D pillar panels by pulling in and forward simultaneously.

Disconnect speaker wires. Set panels aside.

Remove the rear cargo light lens and then light housing by sliding it sideways and let it hang.

Remove both coat hooks by pulling and prying along the seam that joins each hook. Each hook is two pieces that when eventually pulled apart will release as an anchor and allow the headliner sides to drop. I used two small flat screwdrivers and gently worked around the seam perimeter. Refer to photos for expanded hooks.

Un-fasten the C pillar panels down to the seat belts by pulling in toward the center of the vehicle.

Use a bungee cord to keep them leaning toward each other as shown in photo.

Remove the grill from the aspirator with pry tool.

Remove the remaining two round retaining clips (circled in red) along at the rear and center of headliner with pry tool. The headliner should now drop easily at the rear.

Reach in through the rear being cautious not to bend the headliner too much thereby creasing it.

Unplug the old aspirator and plug in the new unit. Check for power.

Position the aspirator over the opening while another person attaches the grill from underneath. If going solo, you MIGHT be able to reattach the grill and hold the aspirator while accessing them from either side. If not, use a zip tie as shown in photo to hold the aspirator in place, secure grill and gently pull out zip tie. Take care to use center most grill holes to help orientate grill snapping into slots on aspirator. Remove zip tie, it’s the prudent thing to do!

Replace center clips in headliner and side hooks followed by the light assembly.

Push C panels back in place, reattach speaker wires, replace D panels and lastly upper plastic trim between the D panels.


Viola! Now celebrate this little victory with a frosty beverage.

Happy Trails!
Here we are doing the same jobs the same way. Good info for others.

There was no way to access that one the way the service manual indicates, so I loosened the headliner as well. Those coat hooks gave me challenges. Watched many vids and still managed to booger them up.
 

S33k3r

Full Access Member
Joined
Aug 14, 2017
Posts
2,301
Reaction score
3,072
Location
Dallas, Texas
Here we are doing the same jobs the same way. Good info for others.

There was no way to access that one the way the service manual indicates, so I loosened the headliner as well. Those coat hooks gave me challenges. Watched many vids and still managed to booger them up.
Those are pretty easy to get from part outs. I don't expect they are expensive, either.
 

Xing_Gateway

TYF Newbie
Joined
Sep 17, 2023
Posts
4
Reaction score
1
Question... is this supposed to be on all the time? I had an issue where my AC would only blow hot or cold. Saw on here that it could be the aspirator. I bought a new one and when I went to replace it the one I took out looked like the attached pic. Yeah, nothing there.


Anyway, I replaced it but AC now just blows only hot air. I haven't really checked to see if I can hear the new aspirator fan going... when is it supposed to be on?PXL_20240309_203408936.jpg
 

Fless

Staff member
Super Moderator
Joined
Apr 2, 2017
Posts
10,859
Reaction score
21,656
Location
Elev 5,280
Question... is this supposed to be on all the time? I had an issue where my AC would only blow hot or cold. Saw on here that it could be the aspirator. I bought a new one and when I went to replace it the one I took out looked like the attached pic. Yeah, nothing there.


Anyway, I replaced it but AC now just blows only hot air. I haven't really checked to see if I can hear the new aspirator fan going... when is it supposed to be on?View attachment 427582

I'm not sure what's supposed to happen, but mine seems to run all the time. If I'm in the truck with the key on "run", but the engine not running (like checking for codes), I can hear it softly running.
 

Forum statistics

Threads
130,118
Posts
1,826,689
Members
93,598
Latest member
04 Z71 learning
Top