Rear Headliner Bass Speaker - Rattle/Buzz

Group 65
Radio and
Accessories

Bulletin Number
65 13 93 (3939)

Woodcliff Lake, NJ
March 1994
Product Engineering

SUBJECT:
Rattle/Buzz from Rear Headliner Bass Speakers

MODELS:
E34 Touring

Situation:
At high volume levels, the rear bass speakers mounted in the headliner panel of E34 Touring vehicles may cause the headliner panel and other close components to buzz and rattle.

Cause:
Insufficient sealing of the bass speaker cavity allows air to pass from the rear of the speaker to other areas close by. The resulting air movement can cause the headliner panel, wires, and cargo lamp housing to resonate.

Correction:
In the case of a customer complaint, a special damping material kit can be installed to drastically reduce the effect. The kit consists of fiber damping material, and a self-adhesive foam fing for each rear bass speaker. When installed, the kit components substantially reduce the air movement in between the speaker and the roof panel.

Procedure:
1. Pry down the two bass speaker bezels from the headliner. Use care not to damage the headliner material. Remove the two forward tweeter covers.

2. Unscrew the four screws of each rear speaker, and disconnect the speaker wiring. Note the orientation of each speaker as it is removed.





3. Pack each bass speaker cavity with a strip of the white fiber insulation. The insulation should be wound around the circumference of the cavity loosely. Make certain the gap between the roof skin and the interior roof panel is covered. Do not use adhesive. Refer to the illustration.

4. Attach a black foam ring to the back side of each bass speaker. Simply peel off the wax paper backing and press into place. The foam ring should just clear the screw holes on the corner of the speaker.

5. Reconnect the wiring, and install the bass speakers. The speaker frame should compress the black foam ring against the interior roof, panel. Tighten the screws firmly.





6. Tape down the wiring near the tweeter speakers. Make certain that no components in this area are free to rattle. Use an adhesive or putty material such as "dum-dum" on the cargo lamp housing and nearby components. All loose wiring should be secured with wide adhesive tape.

Parts Information:

Description Part Number

Insulation Kit 65 12 4 377 170

Warranty Information:
Parts and labor are reimbursable under the terms of the applicable BMW

New Car Limited Warranty.

Defect Code: 65 12 00 39 00

Labor Operation: 00 51 005 Install Insulation Kit

Labor Allowance: 8 FRU