PROM I.D. NOT RECOGNIZED BY THE T-100 (GM CAMS) TERMINAL. GMC Truck GMC G Van 1988

IT IS RECOMMENDED THIS GO OUT AS A DCS MESSAGE.

IT IS IMPORTANT TO KEEP THE T-100 (GM CAMS) TERMINAL UPDATED WITH THE LATEST AVAILABLE CD ROM (COMPACT DISK - READ ONLY MEMORY). CALIBRATION (PROM) INFORMATION CHANGES WITH EACH NEW VERSION OF THE CD ROM. PRODUCTION RUNNING CHANGES AND SERVICE FIXES DRIVE THESE UPDATES.

IMPORTANT: THERE MAY BE A TIME DELAY BETWEEN PRODUCTION AND CAMS INFORMATION. SERVICE PARTS MAY NOT BE IMMEDIATELY AVAILABLE FOLLOWING A PRODUCTION RUNNING CHANGE.

IF THE PROM IDENTIFICATION IN A VEHICLE IS NOT RECOGNIZED BY THE T-100 (GM CAMS) TERMINAL WHEN PERFORMING DIAGNOSTICS, ADDITIONAL HELP IS AVAILABLE THROUGH THE GM SERVICE PARTS ORGANIZATION PARTECH BY CALLING 1-800-433-6961. DIAGNOSTICS FOR THE VEHICLE CAN BE CONTINUED WITHOUT PROM VERIFICATION BY USING THE PROM BYPASS FEATURE.

THE SCANNER CALIBRATION PROM IDENTIFICATION NUMBER WILL MATCH THE LAST FOUR DIGITS OF THE PRODUCTION CONTROLLER PART NUMBER. THE CALIBRATION PROM BROADCAST CODE (FOUR LETTERS) WILL MATCH THE PRODUCTION CONTROLLER BROADCAST CODE. IF ALL THESE ITEMS CHECK OUT, THEN THE CONTROLLER HAS NOT BEEN CHANGED FROM ITS ORIGINAL PRODUCTION STATE. EACH AND EVERY VEHICLE MUST PASS A PROM IDENTIFICATION CHECK AT THE ASSEMBLY PLANT AND WAS CORRECT AT THE TIME OF MANUFACTURE.

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.