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Audible Pop/Static Noise Heard Through Radio Speakers on AM Radio Band with Brake Apply (Check Body Grounds and Replace Center High Mounted Stop Lamp Assembly, If Necessary)

Subject:Audible Pop/Static Noise Heard Through Radio Speakers On AM Radio Band With Brake Apply (Check Body Grounds and Replace Center High Mounted Stop Lamp Assembly, if Necessary)

Models:2005-2006 Cadillac CTS, CTS-V
Built Prior to VIN Breakpoint 60134475



Condition

Some customers may comment about a audible static or pop noise heard through the radio speakers. This condition occurs when radio is on AM band with brake apply.

Cause

This condition may be due to poor body grounds or airborne electro-magnetic interference (EMI) from the neon center high-mounted stop lamp (CHMSL).

Correction #1

Disconnect the CHMSL connector and determine if the condition has lessened. If yes, verify proper circuit grounding. Pay special attention to the large body grounds G401 and G402 located in the rear compartment at the left and right floor rails. Ensure that none of the wire strands are broke at the terminal crimp. If the grounds check out to be good, proceed to Correction #2 below.

Correction #2

Replace the CHMSL assembly using the replacement procedure in SI. This new lamp assembly has additional shielding to reduce the EMI.

Parts Information

Part Number

Description

15778802

High Mounted Stop Lamp

Warranty Information

For vehicles repaired under warranty, use:

Important: Only one of the labor operations below may be submitted for the warranty claim.

Labor Operation

Description

Labor Time

N9556*

Check Body Grounds and Repair if Necessary

0.3 hr

B9793*

Replace Center High Mounted Stop Lamp (Includes Time to Check Body Grounds)

0.7 hr

*This labor operation is for bulletin use only. It will not be published in the Labor Time Guide.