SMU - SECTION 5E1B - VCM (LB4) FOUR WHEEL ANTILOCK BRAKE

SUBJECT: SERVICE MANUAL UPDATE - SECTION 5E1B - VCM (LB4) FOUR WHEEL ANTILOCK BRAKE SYSTEM

MODELS: 1994-95 CHEVROLET AND GMC TRUCK S/T MODELS

THIS BULLETIN REVISES PAGES 38-39, 42-43, 46-47, 50-51, 54-55, 58-59, AND 66-67 IN SECTION 5E1B OF THE 1994-95 S/T SERVICE MANUALS.

MULTIPLE DIAGNOSTIC TROUBLE CODES MAY SET IF A SHORT TO BATTERY IN THE ABS PULSE WIDTH MODULATOR CIRCUITRY OCCURS.

CURRENT DIAGNOSTICS INSTRUCT THE TECHNICIAN TO ERRONEOUSLY REPLACE THE VEHICLE CONTROL MODULE (VCM).

ON LB4 EQUIPPED VEHICLES, A NEW PART NUMBER IS BEING RELEASED FOR THE VEHICLE CONTROL MODULE. THE NEW PART NUMBER 16230703 WILL DIRECTLY REPLACE THE EXISTING 16184738 PART NUMBER.

PRIOR TO REPLACING THE VEHICLE CONTROL MODULE, USE THE ATTACHED DIAGNOSTIC CHARTS WHICH HAVE BEEN REVISED TO AID IN CORRECTLY DIAGNOSING THE PROBLEM.

PARTS INFORMATION:

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

FIGURES: 0 ATTACHMENTS: 14

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.

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