Audio - Front/Rear Bose Speakers Wired Out of Phase
89cdadillac08Bulletin No. T-89-114
File in Group 9
Number 60
Corp. Ref. No. 919603
Date June, 1989
Figure 1 - Pin-Out/Wire Colors:
SUBJECT: FRONT/REAR BOSE SPEAKERS OUT OF PHASE
MODELS AFFECTED: 1989 TWO-DOOR DE VILLES AND FLEETWOODS
Some 1989 two-door Cadillac DeVilles and Fleetwoods built between VIN range 200000 and 220000 and equipped with the Bose radio option (UQ4) may exhibit a condition of a noticeable peak in the mid-base frequency response. (The owner may comment on unpleasant audio system base response.) This may be caused by the front/rear Bose speakers being wired out of phase. To repair this condition use the following procedure:
1. Verify that the vehicle is a 1989 DeVille or Fleetwood (two-door) within the VIN range 200000 to 220000.
2. Make sure the radio has been powered off.
3. Unscrew the two speed-nuts to the right rear Bose enclosure.
4. Pull the enclosure down and toward the center.
5. Peel back the upper right corner of the seat-back trunk trim and pull the Bose speaker connector forward.
6. Disconnect the connector. Verify the enclosure side connector pin-out/wire colors are as shown in Figure 1.
7. If the connector is not wired correctly, back out the + and - audio leads from cavities C and D, and reverse them. (Do not reverse the wires on the vehicle harness side of the connector.)
8. Reconnect the speaker connector.
9. Reinstall the Bose enclosure by sliding into position and pressing on the speed-nuts.
10. Repeat steps 3 through 9 for the left enclosure.
For warranty purposes use Labor Operation T6375 at .3 hour for both left and right side.