2003 GMC SIERRA Electrical System Problems

VEHICLE GOES INTO REDUCED ENGINE POWER MODE AT INTERSTATE SPEEDS WITHOUT WARNING AND INCREASES RISK OF BEING REAR ENDED, DOES NOT HAVE ENOUGH POWER TO SAFELY GET THE VEHICLE OFF THE ROAD WHEN IN THE LEFT LANE WITH OTHER CARS BEHIND. MORE INSTANCES OF THIS SAME SCENARIO OVER THE PAST FEW MONTHS THAN I CAN COUNT. THROTTLE BODY HAS BEEN CLEANED. THERE ARE TOO MANY INTERNET FORUM POSTS DETAILING MANY DIFFERENT PARTS HAVING BEEN REPLACED BY DEALERSHIPS AND OTHER MECHANICS AND THE PROBLEM STILL EXISTING TO JUST START REPLACING PARTS BECAUSE THE COSTS TOO QUICKLY IS UNSUSTAINABLE. *TR

TL* THE CONTACT OWNS A 2003 GMC SIERRA HD. THE CONTACT STATED THAT THE WIRING SYSTEM CAUSED THE BATTERY AND THE ALTERNATOR TO MALFUNCTION. IN ADDITION, THE DASH CLUSTER MALFUNCTIONED AND THE REDUCED ENGINE POWER WARNING LIGHT REMAINED ILLUMINATED. THE CONTACT HAD TO RESTART THE VEHICLE FOR THE DASH CLUSTER TO FUNCTION PROPERLY. THE CONTACT TOOK THE VEHICLE TO THE DEALER WHERE HE WAS ADVISED THAT THERE WAS AN UNKNOWN ELECTRICAL ISSUE WITH THE VEHICLE. THE VEHICLE WAS NOT REPAIRED THE FAILURE MILEAGE WAS 170,000.

TL* THE CONTACT OWNS A 2003 GMC SIERRA. THE CONTACT STATED THAT THE VEHICLE WAS PARKED AND THE ENGINE WAS TURNED OFF WHEN HE HEARD A NOISE AND NOTICED THAT THE AIR CONDITIONING BLOWER HAD INDEPENDENTLY ACTIVATED. THE FAILURE RECURRED AND THE BATTERY WAS DISCONNECTED IN ORDER TO DEACTIVATE THE BLOWER MOTOR. THE VEHICLE WAS TAKEN TO THE AUTHORIZED DEALER WHERE THE BLOWER MOTOR RESISTER WAS REPLACED. THE MANUFACTURER WAS MADE AWARE OF THE DEFECT AND THEY INFORMED THERE WAS NO RECALL. THE APPROXIMATE FAILURE MILEAGE WAS 111,000.

THE SPEEDOMETER IN THE TRUCK REGISTERS FALSE MPH. FOR EXAMPLE WHEN PARKED THE SPEEDOMETER READS 50 MPH, WHEN TRAVELING ON THE ROAD THE SPEEDOMETER WILL REGISTER 80 MPH AND THE ACTUAL SPEED MAY BE ONLY 30 MPH. *TR

DRIVING 2003 SIERRA 2500 HD 4WD CREW CAB AND ALL OF SUDDEN THE SPEEDOMETER NEEDLE QUIT STOPPED ON ZERO AND NEVER MOVED. THEN THE INSTRUMENT GAUGES OR CLUSTER COMPLETELY STOPPED WORKING. THE DEFECTIVE STEPPER MOTOR IN THE CLUSTER IS THE PROBLEM. *TR

SPEEDOMETER WORKING ERRATICALLY OR NOT WORKING AT ALL. VERY DANGEROUS AS WE WERE ON THE FREEWAY WHEN IT HAPPENED. *NM

SPEEDOMETER STOPPED WORKING ON MY 2003 GMC SIERRA. IT IS STUCK ON 65 MPH. *NM

INACCURATE SPEEDOMETER - AFTER AN HOUR WITH CRUISE CONTROL SET ON 65 MPH DURING EACH DOWN HILL SEGMENT THE SPEEDOMETER WOULD INCREASE ABOUT TWO MILES PER HOUR. ON THE UP HILL SEGMENT IT DID NOT DECREASE TO 65. AFTER THE SECOND DOWNHILL SEGMENT IT READ 67, THE NEXT IT READ 69, AFTER ABOUT 20 UP HILL, DOWN HILL CYCLES, SPEEDOMETER INDICATED OVER 100 MPH. THE RPM WAS ABOUT 1900 WHICH IS ABOUT 65 MPH. WHEN I STOPPED FOR GAS, THE SPEEDOMETER RESTED AT 42 MPH. OVER THE NEXT SEVERAL DAYS IT WORKED BACK TO ZERO WHEN THE VEHICLE WAS STOPPED. ONE WEEK LATER THE EVENT OCCURRED AGAIN. TODAY I SPOKE TO THE SERVICE ADVISOR AT MY DEALERSHIP AND HE SHOWED ME A LIST OF PEOPLE WAITING FOR "INSTRUMENT CLUSTERS" FOR THIS SAME PROBLEM. *NM