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Audio System - Noise/Distortion on AM/FM/XM Etc.

Bulletin No.: 05-08-44-031A

Date: November 16, 2005

ADVANCE SERVICE INFORMATION RESOLUTION

Subject:
Noise, Distortion, or Poor Reception When AM, FM, XM, OnStar(R), CD, or Auxiliary Input Selected (Reprogram Radio)

Models:
2006 Chevrolet Impala, Monte Carlo

with Radio (RPOS US8/US9)

Built Up To and Including VIN Breakpoints 69181114

Supercede:

This bulletin is being revised to provide the correction information and a VIN breakpoints for Advanced Service Information Bulletin 05-08-44-031. Please discard. Corporate Bulletin Number 05-08-44-031 (Section 08 - Body & Accessories).

Condition

Some customers may comment on noise, distortion, or poor reception when one or more radio functions (AM, FM, XM, OnStar(R), CD, auxiliary input) is selected or when the door ajar chime or turn signal audible indicator is activated. Refer to Additional Information section of this bulletin regarding customer concerns related to this condition.

Cause

The digital signal processor may be incorrectly configured when the radio is turned on.

Correction

Important:
DO NOT reprogram U1C radios with these calibrations.

Do NOT replace the radio or the antenna module.

If the owner experiences this condition and it meets all the criteria in the Additional Information section, reprogram the radio with the latest available calibrations (TIS 11.0 2005 or later). The appropriate calibration can be found under "Operating System" in the Radio menu.

Additional Information

The customer may have a concern (noise, distortion, or poor reception) with one function at one time and a different one at another time. Concerns may affect one or more functions, such as FM only, AM and FM together, or even all radio functions at once.

The concerns above MUST meet ALL of the following criteria or this correction (new software calibration) will not address the concerns:

- The concern(s) must be present the first time the customer uses a radio function after the car is started.

- The concern(s) must not start occurring and/or stop occurring while the car is running.

- The concern(s) typically stops occurring when the customer shuts the car off and restarts it.

Important:
If the customer concern(s) do not meet ALL of the above criteria, other areas of the vehicle consistent with the concern(s) should be investigated and corrected. The radio function(s) should then be re-evaluated as noted above.

Dealer Action

^ Please contact all customers that were told they would be called when a repair became available.

^ Distribute this information to all dealership technicians and service advisors.

Warranty Information





For vehicles repaired under warranty, use the table.





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