GM Service Manual Online
For 1990-2009 cars only

SERVICE GUILD: SERVICE REPL. ECM WITH PROM INSTALLED

Model and Year: 1981-88 ALL MODELS

It has been brought to our attention that some service replacement electronic control modules (ECM's) have contained a PROM. A PROM should not have been included in a replacement ECM as it may not be the correct PROM for the vehicle.

When this situation is encountered, the PROM should be removed from the replacement ECM and the PROM from the vehicle should be installed.

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.