Hello All.
At idle I’m hearing a Low humming sound. It sounds like its coming from the gauge cluster. I turning the wheel thinking it was the power steering, nope. I revved the engine and it goes away but once idle hits…RRRRrrrrrr. What is that? As I driving I don’t hear it. Does anyone else hear this? The car would be “Lexus” quiet if it weren’t for this sound. RRRRrrRRRRR It almost sounds electronic. It’* louder inside the car. Under the hood, not so much.
What’* gives??

Do you hear it if the radio is off? How about if the climate control is off. not just the fan, the whole unit. When the fan is all the way down it will still turn the fan.

Since it'* only at idle and not in the engine bay, it may be a broken mount somewhere under the car. Have you crawled underneath the car recently for a visual inspection?

Regardless, it'd be best if you can you grab a camera and take a short video of it. You described it well, but I'd love to hear it.

I tried to do the video but it came out in a MP4 format. I need to convert it. Over the weekend, my cluster failed! Today the gas gauge came back but I don’t know if it’* accurate and the speedo works but is off. I just searched on a fluke and look what I found:



Service Information Chevrolet TrailBlazer - 4WD | Bravada, Envoy, Rainier, TrailBlazer (VIN */T) Service Manual | Document ID: 1870974
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#04-08-49-015A: Noise Coming From Instrument Panel Cluster (Replace Instrument Panel Cluster (IPC)) - (Nov 6, 2006)


Subject: Noise Coming From Instrument Panel Cluster (Replace Instrument Panel Cluster (IPC))


Models: 2003-2005 Buick LeSabre

2003-2007 Buick Rendezvous

2004-2005 Buick Rainier

2003-2006 Cadillac Escalade, Escalade ESV, Escalade EXT

2003-2005 Chevrolet Cavalier, Impala, Monte Carlo

2003-2006 Chevrolet Avalanche, Suburban, Tahoe, TrailBlazer EXT

2003-2007 Chevrolet Silverado Classic, TrailBlazer

2003-2007 Chevrolet Kodiak Models

2004-2006 Chevrolet SSR

2003-2006 GMC Envoy XL, Yukon, Yukon XL

2004-2005 GMC Envoy XUV

2004-2007 GMC Envoy

2003-2007 GMC Sierra Classic

2003-2004 Oldsmobile Bravada

2003-2005 Pontiac Aztek, Bonneville, Sunfire

2003-2005 HUMMER H2


Attention: Appropriate repair is based on vehicle build date. Use GMVIS to determine the vehicle build date.

Condition:
Some customers may comment on a noise coming from the instrument panel cluster (IPC) while driving or on initial start-up. Instrument clusters may contain stepper motor gauge. that can make noise during the following conditions:

• Initial startup >(gauges zero/reset)

• Gauge ascending and descending >(gauge sweeping)

• Engine idle (tachometer ticking)

• Engine off >(gauges reset to zero)

Cause:
The cause of this noise may come from the instrument cluster gauge., which contain stepper motors. As the gauge pointer moves, rotors and gears inside the stepper motors are rapidly rotated and rubbing one another. It is natural to generate mechanical noise due to all gear movement. However, it will not in any way affect the performance and durability of the cluster.

Correction:
For vehicles built or clusters remanufactured on or after March 1, 2005, DO NOT exchange the IPC for a noise only concern. As of March 1, 2005, all stepper motor improvements are in place and noise from the cluster is within the acceptable performance. Any remaining noise from the IPC is inherent to the system design and replacing the cluster for just a noise concern will more than likely result in a similar noise. Please inform the customer that the IPC is performing within the acceptable guideline. If after the customer has been informed and still insist to replace the cluster, then the cluster should be replaced.

For vehicles built or clusters remanufactured prior to March 1, 2005, clusters should be replaced for noise concern.

Clusters should continue to be replaced for any concern affecting the functionality of the IPC.

Parts Information:
Cluster exchange units can be obtained from an authorized Electronic Service Center.

This was me all day!! And now my cluster has failed! I also read this:
http://www.aboutautomobile.com/Compl...strument+Panel

FYI for those of you who are dealing with this.

The dealership has my car. I hope they are aware of this. Maybe they will tell me I have gremlins in car.