Denali radio noise [Archive] - Chevy TrailBlazer, TrailBlazer SS and GMC Envoy Forum

: Denali radio noise

02-10-2006, 12:18 PM
I just picked up my 06 Denali after it has been in the shop for the last 2 weeks for a radio noise. My Denali has the NAV BOSE system. The radio noise occurs mostly once it warms up to operating temperatures. The noise is dependent on engine RPM (IE you hear it better as the revs increase). It does it in any gear including park and any mode of the transfer case. Has any one else had this problem? I'm going to meet with the service manager today and have him compare it to a new vehicle if need be. I wouldn't have bought this vehicle if it whined like this on the test drive.

If it is normal and common, you can hear the noise good when it is in park with the radio barely on. The volume can't be totally off but just about 1/2 turn on.

Any help would be great.

This is real stupid and annoying.

02-10-2006, 12:51 PM
If it's alternator whine you are hearing, there could be something wrong with the alternator or the radio since from your description this noise is getting into the audio circuit before the volume control if you can turn it down and not hear the noise. Sometimes a battery going bad can cause it too, because the battery isn't filtering and smoothing out the ripple in the alternator's DC output like it should. They (aftermarket) sell filters for this problem that go inline with the DC power to the radio or amplifier, whichever it's getting into. Should not do it though with the OEM factory setup.

02-10-2006, 12:55 PM
As of now they already replaced grounds in the radio system, the NAV/Radio unit itself and put about 2-3 supressors in-line. I was thinking it might be the battery or alternator also. I'm still waiting for the service manager to get back from a meeting or something.

02-10-2006, 01:50 PM
The pitch of the whine changes with RPM?

02-10-2006, 02:01 PM
The pitch of the whine changes with RPM?

Yes, in any gear, any mode of 4WD. It is noticeable above 1500rpm

Windy City
02-10-2006, 02:23 PM
Hmmm, possibly a bad engine ground causing a ground loop? I would also question the alternator since it is most likely the source of the noise.

Envoy Fan
02-10-2006, 04:57 PM
Dave, hope you get this issue resolved soon. Even with a loaner vehicle this has got to be a real PIA to deal with.

02-10-2006, 07:07 PM
I have my Denali at least for the weekend. The service manager went for a drive with me but he couldn't hear the noise. I'm thinking that it is NOT the radio system because the noise comes from the trunk area even when you fade/balance the speaker to one speaker in the front. My guess is that it is the air ride suspension or possibly the fuel pump since that are the main electrical things back there. It is not the normal air ride suspension compressor noise. It ONLY occurs with the radio on and progressively gets louder as RPMs increase. Then decreases when the tranny shifts until the RPMs build back up again. It sounds like ignition noise through the radio. Older cars were great for doing it.

Anyone know if the fuel pump/air ride suspension power wires run near the radio wires?

At least they seem to be working with me because I really love the Denali.

It won't do it on the interstates though or at least I can't hear it due to the wind noise. It looks like I need to take more road trips instead of slugging around the city.

02-14-2006, 04:57 PM
Found this today that may apply to your situation if yours has the UQA Bose amp..... from the Feb 06 GM Techlink newsletter

Whine Noise from Speakers

Some owners of a 2006 Buick
Rainier, Chevrolet Trailblazer,
GMC Envoy or Saab 97x may
comment about a generator
whine noise heard from the
vehicle’s speakers. This will be
noticed with the radio on or off,
engine running.
This applies to short wheelbase
vehicles equipped with UQA
Bose Amplifier only. The amplifier
on the short wheel base is located
in the right rear quarter panel
behind the trim. The harness is
routed along the right side and
follows the contour of the floor
close to the sill plates. If the harness
is not kept tight where the
second row seat fastens to the
floor, the harness may be pinched
or trapped under the front corner
of the second row seat frame
or bolt.
Open the passenger rear door
and remove the sill plate. Locate
the harness that travels along this
sill plate area and follow to the
second row seat frame outer
mounting bolt. If you suspect that
the harness is pinched, remove
the second row seat and remove
the trapped harness. Repair any
damaged wires and secure the
harness to prevent damage in
the future.

02-14-2006, 05:07 PM
I'm no expert, but that sounds like a pretty good find, tblazed. :)

02-14-2006, 10:26 PM
I'm no expert, but that sounds like a pretty good find, tblazed. :)
Yeah, that might be the answer to your problem Dave.

02-14-2006, 10:43 PM
I'll mention it to my service manager. Right now he couldn't hear the noise when we went for a drive. Everyone in my family can hear it pretty well.

I think I'll wait till after holiday weekend so I can enjoy my car this weekend.

02-14-2006, 10:46 PM
Do you know the link to the article? I use to know it but I lost it. Mine only does it with the radio on but it is worth a shot. My Denali does have the Bose radio.



02-14-2006, 11:15 PM
I'm no expert, but that sounds like a pretty good find, tblazed. :)