SPEEDOMETER MOMENTARY DROP. GMC Truck GMC C Pickup

SUBJECT: SPEEDOMETER MOMENTARY DROP WHEN TURNING ON PARK LAMPS, TURN SIGNALS OR HAZARD FLASHERS (SEND I/P CLUSTER TO DELCO REPAIR STATION)

MODELS: 1993-94 CHEVROLET AND GMC TRUCK C/K MODELS 1994 CHEVROLET AND GMC TRUCK S/T PICKUP MODELS

CONDITION:

SOME SPEEDOMETERS IN THE ABOVE VEHICLES MAY MOMENTARILY DROP WHEN THE TURN SIGNAL, PARK LAMP, OR HAZARD FLASHER IS TURNED ON. THIS CONDITION OFTEN OCCURS AT SPEEDS OVER 60 MILES PER HOUR.

CAUSE:

SLIGHT SYSTEM VOLTAGE DROP WHEN THE EXTRA LOAD FROM THE LIGHTS IS ADDED.

CORRECTION:

REMOVE THE INSTRUMENT CLUSTER AND SEND IT TO THE LOCAL DELCO REPAIR STATION. REPAIR STATIONS ARE AWARE OF THE CONDITION AND HAVE PARTS AVAILABLE TO REPAIR THE CLUSTER. THEY WILL ADD A CAPACITOR TO THE POWER CIRCUIT TO ASSURE A CONSISTENT POWER FLOW DURING POWER UP OF THE ABOVE MENTIONED LAMPS. BE SURE TO CLEARLY DESCRIBE THE CONDITION ON THE DELCO REPAIR ORDER ACCOMPANYING THE CLUSTER.

WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OP DESCRIPTION LABOR TIME N4180 INSTRUMENT PANEL CLUSTER R+R USE PUBLISHED LABOR OPERATION TIME

FIGURES: 0

CAPTIONS:

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.