For 1990-2009 cars

# WIPER MOTOR INTEFERES W/RADIO INSTALL NOISE SUPPRESSOR

A STATIC OR A WHIRRING NOISE MAY BE ENCOUNTERED IN THE RADIO DURING WINDSHIELD WIPER OPERATION ON 1980-1982 OMEGA MODELS EQUIPPED WITH A FIXED MAST ANTENNA. TO CORRECT THIS CONDITION, INSTALL A WINDSHIELD WIPER NOISE SUPPRESSOR PACKAGE (PART NO. 477326) IN THE WIPER MOTOR HARNESS. PARTS ARE AVAILABLE FROM WDDGM. IF THE NOISE SUPPRESSOR PACKAGE DOES NOT ELIMINATE THE NOISE, USE THE FOLLOWING PROCEDURE: 1.DISCONNECT ANTENNA FROM THE RADIO. THE NOISE SHOULD REMAIN AS LONG AS THE RADIO CASE STILL HAS A GOOD GROUND. 2.IF SO, CUT THE BLACK GROUND WIRE WHICH GOES INTO THE BLACK POWER PLUG FOR THE RADIO. 3.INSTALL A GROUND STRAP FROM THE RADIO CASE TO A GOOD GROUND (FIG. 1). THIS SHOULD ELIMINATE THE NOISE.

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.