GM Service Manual Online
For 1990-2009 cars only

CS-144 GENERATOR-REPAIR REPLACE RECTIFIER BRIDGE

1987 BONNEVILLE

When replacing the rectifier bridge in CS-144 generators, it is very impartant to use the correct replacement rectifier bridge, which currently is part number 1989774. This bridge uses special avalanche rectifiers which protect the generator and other vehicle electrical components from high voltages, including transient voltages.

While the 1988976 rectifier bridge, for the 17SI generator, is the same in size and shape as the 1989774, it is not the same electronically, and must not be used in CS-144 generators. Damage to the generator and other vehicle electrical components may result.

When replacing electrical parts on vehicles with electronic components, it is necessary to refer to the parts lists to determine the correct replacement part number. Do not use substitutes.

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.