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For 1990-2009 cars only

UQA Bose Radio Automatic Volume Clarification - kw inoperative operation radio volume GMT360 GMT370

Subject:UQA Bose® Radio Automatic Volume Clarification

Models:.



When servicing the vehicle with the VIN you entered, the following diagnosis might be helpful if the vehicle exhibits the described symptoms.

Condition/Concern:

Automatic Volume feature diagnosis on the UQA Bose® radio.

Recommendation/Instructions:

"Auto Vol" on the UQA (Bose®) radio works much differently that the "Speed Compensated Volume" (SCV) system on non-UQA radios. The sensor is located on the passenger side of the overhead console and works on about 1-3 mV.

Feature operation can be tested as follows:

  1. Set the radio volume at the 2 or 3 bar mark on the display.
  2. Turn the HVAC blower on High.
  3. Turn the auto volume feature ON and OFF (or Low, Med, High and OFF on non-Bose radios). The difference should be noticeable.

With the system ON, the dynamic equalization is changed to compensate for background noise. The sound quality difference will be more noticeable at lower speeds. There is NO input from the vehicles speed sensors.

Reference the Owners manual for further details.

Please follow this diagnosis process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed. If these steps do not resolve the condition, please contact GM TAC for further diagnostic assistance. This diagnostic approach was developed for the vehicle with the VIN you entered and should not be automatically be used for other vehicles with similar symptoms.

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Models:

(2002-2004 Chevrolet Trailblazer and Trailblazer EXT) and (2002 - 2004 GMC Envoy and Envoy XL) and (2002 - 2003 Oldsmobile Bravada) and (2004 Buick Rainier)