Audio System - Speaker Buzzing in 4X4 Mode
TSB SB05-13-S002Buzz Type Noise Coming From Rear Speakers
ISSUE DATE: MARCH 2005
Affected Vehicles:
2004-2005 Isuzu Ascender (US/UT) with Speaker System Premium Performance Enhanced (Bose(R)) Audio (RPO UQA) and 4WD.
Service Information
Condition:
Some customers may comment on a buzz type noise heard through the rear speakers. This noise can only be heard when the radio is on, volume low and while driving in 4WD mode.
Possible Cause:
The noise USUALLY occurs above 32 km/h (20 mph) and is related to the active transfer case operation.
Correction:
Important:
This procedure will only correct the noise related to transfer case operation. It will not correct the speed sensitive whine type noise, commonly referred to as alternator whine.
Service Procedure
Perform the following procedure to reduce the rear speaker buzz noise caused by the active transfer case.
1. Remove the left side IP closeout panel.
2. Remove the transfer case control module (1) and mounting bracket (2) from the IP mag beam.
3. Disconnect the C3 connector from the transfer case control module. Refer to the Electrical Troubleshooting Manual (ETM) for component and connector views.
4. Remove the wire and terminal from cavity (A) from C3 connector. Tape back.
5. Construct a new ground wire using terminals P/N 8-12047-767-0 and P/N 8-12089-496-0. Route this wire through the grommet from the IP out to the engine compartment.
6. Install the new ring terminal onto ground stud (G105) located on the bulkhead just above the brake booster.
7. Install the new terminal into cavity A of connector C3.
8. Connect the C3 connector to the transfer case control module.
9. Install the transfer case control module and mounting bracket to the IP mag beam.
10. Install the left side IP closeout panel.
Parts Information
Warranty Claim Information
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