HVAC FRT. BLOWER WHINE NOISE (REPAIR HVAC PWR. MODULE GRD.)

SUBJECT: HVAC FRONT BLOWER WHINE NOISE (REPLACE HVAC POWER MODULE)

VEHICLES AFFECTED: 1992 "E AND K" MODELS

Some 1992 Sevilles (before VIN breakpoint 800241) and 1992 Eldorados (before VIN breakpoint 600136) may experience an HVAC front blower whine noise when the blower is operating with the engine running but is most noticeable under the following circumstances:

o HVAC front blower on low speeds o Engine at operating temperature o High electrical load (lights on, rear defogger on, A/C on) o Radio off o Engine rpm varying from 1500-2000 rpm o Owners may describe the noise as a generator or radio whine

The HVAC power module ground at the generator may be the cause of the noise. To repair this condition remove the power module ground from G103 and relocate it to G301 by splicing the power module ground wire to the cruise servo ground wire. To relocate the power module ground use the following procedure:

1. Remove the HVAC power module Maxi(R)-fuse #4, located in the right-hand (inboard) Maxi(R)-fuse block (underhood). Refer to the 1992 Eldorado/Seville Preliminary Service Information Manual page 8A-201-2A, Figure A.

2. Cut and strip back 5/16" of insulation from the power module ground wire on the ring terminal at the generator ground stud. The power module ground wire has the smaller diameter of the two ground wires at the ground stud.

3. Remove the bolts securing the cruise servo bracket.

4. Remove tape from the cruise servo branch of the underhood wiring harness.

5. Cut the cruise servo ground wire 6-10" from the cruise servo connector so that both ends of the servo ground wire can be spliced to the power module ground wire. Strip both ends of the servo ground wire.

6. Splice the power module ground wire to both cruise servo ground wires using environmentally sealed splice clip, P/N 12089190 (blue). Splice clips are included with the Terminal Repair Kit, J-38125. The wire repair instructions for using splice clips are included with the Terminal Repair Kit and in Section 8A-5 of the Service Information Manual.

7. Reinstall tape on cruise servo branch.

8. Reinstall the cruise servo bracket and HVAC Maxi(R)-fuse #4.

9. Verify HVAC front blower operation.

If vehicle is being repaired under warranty use: .5 hours.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.