SEVERAL INSTANCES WHERE THE SPEEDOMETER READ 0 MPH WHEN TRAVELING AT VARIOUS SPEEDS. ONE INSTANCE WHERE THE SPEEDOMETER READ 120 MPH WHEN TRAVELING AT 65 MPH. ALWAYS OCCURS DURING FIRST TRIP IN MORNING AND THEN SEEMS TO RESET WHEN IT HAS BEEN SHUT-DOWN AND A PERIOD OF TIME HAS PASSED. *JB
2009
ENGINE AND ENGINE COOLING
WHILE DRIVING AT HIGHWAY SPEEDS IN A 2009 CHEVROLET AVALANCHE, THE ELECTRONIC POWER WILL SHUT OFF TO THE VEHICLE ON AN INTERMITTENT BASIS. INTERIOR LIGHTS FLASH DISORIENTING THE DRIVER, LOCKS SWITCH ON AND OFF, POWER TO THE ENGINE IS INTERMITTENT AND SURGES FORWARD UPON POWER COMING BACK. TRACTION ASSIST AND PARKING ASSIST TOGGLE ON AND OFF IN RAPID SUCCESSION CAUSING DRIVER TO NEARLY LOSE CONTROL OF VEHICLE. INCIDENTS LAST FOR APPROXIMATELY 10 SECONDS AT A TIME. INCIDENTS HAPPEN IN CLUSTERS AND MAY GO WEEKS OR MONTHS AT A TIME WITHOUT INCIDENT. HAS OCCURRED APPROXIMATELY 10 TIMES IN THE LAST YEAR AND USUALLY AFTER THE INCIDENT THE VEHICLE HAS DIFFICULTY STARTING AFTERWARDS. POWER WILL BE COMPLETELY OFF. AFTER A PERIOD OF TIME, VEHICLE WILL START BACK UP AND APPEAR TO BE FINE UNTIL THE NEXT INCIDENT. HAVE TAKEN THE VEHICLE TO DEALER (STILL UNDER WARRANTY) ABOUT SIX TIMES FOR THIS PROBLEM AND CONTACT GM TECHNICAL ASSISTANCE. HAVE BEEN TOLD THAT SINCE THE VEHICLE'S INTERNAL COMPUTER DOES NOT GENERATE A "CODE" THERE IS NOTHING THAT CAN BE DONE. *TR