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ELECTRICAL INTERFERENCE IN MOBILE (TWO-WAY) RADIO

REVISION: 01/14/97

THIS BULLETIN IS BEING REVISED TO ADD THE 1997 MODEL YEAR AND CHANGE THE LABOR OPERATION NUMBER. PLEASE DISCARD CORPORATE BULLETIN NUMBER 56-96-03 (SECTION 9 - ACCESSORIES). ----------------------------------------------------------------------

SUBJECT: ELECTRICAL INTERFERENCE IN MOBILE (TWO WAY) RADIO (REPROGRAM VCM-A)

MODELS: 1995 CHEVROLET AND GMC TRUCK S/T MODELS 1996-97 CHEVROLET AND GMC TRUCK C/K, S/T, M/L, G, P MODELS, ISUZU, FORWARD AND TILTMASTER 1996-97 OLDSMOBILE BRAVADA WITH 4.3L, 5.0L, 5.7L, 7.4L ENGINES (VINS J, M, R, W, X - RPOS L29, L30, L31, L35, LF6) AND REPROGRAMABLE, VEHICLE CONTROL MODULE (VCM-A)

********************************************************************** CONDITION:

SOME OWNERS OF VEHICLES EQUIPPED WITH VEHICLE CONTROL MODULES (VCM-A) WHO HAVE INSTALLED MOBILE TWO WAY RADIOS, MAY EXPERIENCE ELECTRICAL INTERFERENCE IN THE MOBILE RADIO. THE CUSTOMER MAY COMMENT OF A CONSTANT STATIC OR NOISE IN THE MOBILE RADIO RECEIVER.

CAUSE:

THE INTERNAL OPERATING FREQUENCY OF THE VCM-A MAY AFFECT SOME MOBILE RADIOS.

CORRECTION:

THE ELECTRICAL INTERFERENCE CAUSED BY THE VCM-A MAY BE ELIMINATED BY REPROGRAMMING IT. AN ELECTRICAL INTERFERENCE CALIBRATION IS AVAILABLE ON YOUR TECHLINE TERMINAL. FOLLOW YOUR TECHLINE TERMINAL USER INSTRUCTIONS AND THE APPROPRIATE VEHICLE LINE DRIVEABILITY, EMISSION AND ELECTRICAL DIAGNOSIS SERVICE MANUAL; SECTION 3B.

WARRANTY CLAIMS INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OPERATION LABOR TIME J6355 USE PUBLISHED LABOR OPERATION TIME.

FIGURES: 0 ATTACHMENTS: 0

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.

COPYRIGHT 1995 GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.