For 1990-2009 cars

# RADIO NOISE ON 1981 E,K CARS ECM GROUNDED AT MOUNTING BRKT

NOISE IN THE RADIO ON SOME 1981 E AND K CARS CAN BE CAUSED BY THE ECM BEING GROUNDED AT ITS MOUNTING BRACKET. THE ECM MUST NOT BE GROUNDED TO THE CHASSIS. INSULATE FROM MOUNTING TO CORRECT.

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.