NHTSA Complaint #11660591 — 2024 LEXUS RZ

My 2023 Lexus RZ450e experienced a sudden failure of the 12-volt battery, which completely disabled the vehicle and prevented it from starting. The battery failed while the car was plugged into a Level 2 home charger, but not in ‘Ready’ mode. There were no warning signs or alerts, and I had to call roadside assistance to jump-start the car. After the incident, I brought the vehicle to the dealership. They tested the 12V battery and said it was “fine.” However, during the 100,000-mile maintenance, I specifically requested a battery re-check—and this time, the battery failed the test. This raises serious concerns about the reliability and longevity of the 12V battery in this vehicle, as well as the inconsistent diagnostics at the dealership. If the vehicle had failed to start while I was away from home, I could have been stranded in unsafe conditions. Safety Concerns: The 12-volt battery powers essential systems, including door locks, ignition, and electronic control units. Its failure disables the entire vehicle. The fact that this happened while the car was plugged in, but not in “Ready” mode, suggests a potential design flaw or charging system issue. I’ve also seen reports from other RZ450e owners experiencing similar 12V problems, which may point to a broader systemic issue. Requested Action: Please investigate potential defects in the 12-volt battery system and whether the Lexus RZ450e’s charging system fails to maintain battery health during regular use.