NHTSA Complaint #11065908 — 2017 TOYOTA PRIUS

FRIDAY JANUARY 12, 2018, DROVE VEHICLE 3.5 HOURS ON HIGHWAY DURING PERIOD OF DECLINING TEMPERATURES- 34 TO 29 FAHRENHEIT, WITH SNOW BEGINNING HOUR 2.5. OPERATED FRONT DEFROST CONTINUOUSLY FOR ENTIRE 3.5 HOUR TRIP WITH CABIN TEMP BETWEEN 72 AND 75F. MADE 2 STOPS, 10 MINUTES EACH- ONE AT 1.5 HOURS AND ONE AT 3 HOURS. PARKED OVERNIGHT IN HOME GARAGE AT END OF TRIP. AIR TEMP DECLINED TO 19F OVERNIGHT. BACKED CAR OUT OF GARAGE IN MORNING AND WINDSHIELD CRACKED AT CENTERLINE OF FRONT DEFROST VENT. CRACK HAS CONTINUED TO EXPAND TO POINTS ALMOST EXACTLY 5 INCHES BEYOND EACH END OF DEFROST VENT, THEN STOPPED EXPANDING. PASSENGER SIDE (RIGHT SIDE) CRACK IS ALIGNED EXACTLY WITH CENTERLINE OF DEFROST VENT. AT POINT 5" OUTBOARD OF VENT, PASSENGER SIDE CRACK TURNS DOWN AND EXTENDS TO BOTTOM EDGE OF WINDSHIELD. DRIVER (LEFT SIDE) CRACK IS PARALLEL TO VENT ON LINE 3" BELOW VENT, THEN TURNS UP, CROSSES VENT, AND PARALLELS VENT 3" ABOVE VENT TO TERMINATION OF CRACK AT 5" OUTBOARD OF VENT. NOTHING IMPACTED WINDSHIELD DURING TRIP AND WINDSHIELD WAS NOT CRACKED AT END OF TRIP. ENGINEERING DEFECT- INADEQUATE GLASS STRENGTH- UNABLE TO USE DEFROSTER FOR EXTENDED PERIODS. CRACK CREATED BY STRESS FROM LOCALIZED THERMAL EXPANSION- ALIGNED WITH HEAT SOURCE OF DEFROSTER VENT AT LOWER MIDDLE REGION OF WINDSHIELD. THIS IS FIRST EXTENDED USE OF DEFROSTER IN CAR- PURCHASED MAY 2018. CURRENTLY HAS 21,800 MILES.