While driving my Porsche Taycan through a high-speed intersection, the vehicle suddenly displayed battery and chassis system error messages instructing me to pull over immediately. Before I could safely move the vehicle to the side of the road, it completely lost propulsion, speed control, and steering capability, causing the vehicle to abruptly slow to 0 mph in active traffic and leaving me stranded in the middle of the roadway. This created an immediate safety hazard, as approaching vehicles nearly collided with my car because it effectively performed an unexpected emergency stop without warning. Approximately one month earlier, the vehicle experienced the exact same failure while parked, displaying battery and chassis errors and losing power and steering functionality. The vehicle was towed to an authorized Porsche dealership, where it remained for approximately one month; however, the dealer was unable to diagnose the problem and returned the vehicle to me, stating that no fault could be found. Just two days after the vehicle was returned, the identical failure occurred again while I was driving. After restarting the vehicle multiple times at the roadside, I was eventually able to move it to a safer location, where it failed again shortly thereafter. The vehicle is currently at the Porsche dealership and is available for inspection. The dealership has indicated that the issue may be related to the high-voltage battery but has not yet identified the root cause or completed repairs. The only prior warning of this defect was the nearly identical battery and chassis system failure that occurred approximately one month before this incident.
NHTSA ODI 11746390