The PCM ENABLE SIGNAL TEST in the Electrical Systems Manual has been revised to approach diagnostics in a more direct manner.
Use the following updated test charts for proper Theft Deterrent System Diagnosis:
1991 PARK AVENUE/ULTRA ----------------------- D: PCM ENABLE SIGNAL TEST on Page 189
1992 PARK AVENUE/ULTRA ----------------------- D: PCM ENABLE SIGNAL TEST on Page 205
D: PCM ENABLE SIGNAL TEST on Page 198
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.