NHTSA Engineering Analysis EA04035

THE COMBINATION FRONT TURN SIGNAL/DRL IN MY 2003 SATURN ION COUPES EXPERIENCED SIGNIFICANT EARLY-LIFE FAILURES DUE TO VARIOUS BULB QUALITY ISSUES DUE TO INADEQUATE DESIGN AND MANUFACTURE.THIS PROBLEM TREND APPEARS TO HAVE DISAPPEARED AFTER THE FALL OF 2003.THE CHANGE OF LEAD WIRE MATERIAL NEAR THE START OF MY 2004 VEHICLE PRODUCTION APPEARS TO HAVE REDUCED THE FAILURE RATE FOR MY 2004 SATURN ION COUPES.ALTHOUGH OPERATING TEMPERATURES IN THE SUBJECT VEHICLES' LAMP ASSEMBLIES ARE BELOW THE SOCKET MATERIAL MAXIMUM TEMPERATURE SPECIFICATION, THEY ARE ONLY SLIGHTLY BELOW THE SPECIFICATION.IN DECEMBER 2004, GM REDUCED THE VOLTAGE TO THE LAMP ASSEMBLY IN ORDER TO REDUCE THE TEMPERATURE IN THE ASSEMBLY OF THE SUBJECT VEHICLES.WARRANTY CLAIMS ON THE SUBJECT VEHICLES DO NOT INDICATE AN INCREASING TREND OVER TIME.WARRANTY CLAIM RATE OF SUBJECT VEHICLES (EXCLUDING EARLY MY 2003 CLAIMS) IS NOT SIGNIFICANTLY HIGHER THAN OTHER GM VEHICLES THAT USE COMBINATION TURN SIGNAL/DRLS.A SAFETY-RELATED DEFECT TREND HAS NOT BEEN IDENTIFIED AT THIS TIME.FURTHER USE OF AGENCY RESOURCES DOES NOT APPEAR TO BE WARRANTED.ACCORDINGLY, THIS INVESTIGATION IS CLOSED.THE CLOSING OF THIS INVESTIGATION DOES NOT CONSTITUTE A FINDING BY NHTSA THAT A SAFETY-RELATED DEFECT DOES NOT EXIST.THE AGENCY WILL TAKE FURTHER ACTION IF WARRANTED BY THE CIRCUMSTANCES.SEE ATTACHED SUMMARY REPORT.