NHTSA Complaint #11667104 — 2025 HYUNDAI TUCSON HYBRID

Battery Management System failed Safety-Could not drive on interstate. Very unsafe. Dealer inspected problem afterwards. Warning lights appeared at time of problem. No warnings before. No signs of problem before it happened. SYNOPSIS: After driving through a torrential thunderstorm on the interstate (06-13-25) and as we were getting ready to slow down for our exit on the interstate, we hit the brakes and our SUV gave us a warning. The warning said, "Battery Management System Discharge". The SUV is a hybrid. At this point the SUV locked into E V mode. Our SUV would only go 10 mph which was very dangerous. It should be able to go up to 35 mph in E V mode and then past that, switch into gas mode. As stated, we could only go about 10 mph. We made it to our exit and found a spot to pull off the ramp. We let the SUV sit for a few moments and turned it off. We let it sit for a minute and then turned the car back on. The SUV when we turned it back on gave us a check engine light and still would not go over 10 mph. Luckily we were stopping for dinner. We were able to proceed to our destination. After dinner around an hour or so, when turned the vehicle back on, the SUV still gave us a check engine light. but was able to drive normally and switch between E V and gas modes. We made it home safely at the end of the weekend on 06-15-25. On 6-16-25 we took the SUV to be looked at by the dealer we purchased it from. Our phone app showed code DTC P0AA600. We gave the code to the staff. The staff inspected the SUV. The report stated, "customer states stopped driving and there code P0AA600 Battery Warning Light NPF Could not duplicate problem. Tech scanned for codes Code P0AA600 was found as a history code. Tech checked live data and everything came back within spec. Followed the flow chart procedure for the code. Check for BMS isolation faults none found. Check 12volt battery. Battery is good". We drove it home and filed this report.