NHTSA Complaint #11668382 — 2020 BMW 330I

While driving, my 2020 BMW 330i suddenly entered “drivetrain limited power” mode, severely restricting acceleration and overall performance. Upon diagnostic review, the cause was found to be a failure of the Heat Management Module (HMM). This created a hazardous situation as the vehicle unexpectedly lost power while merging into highway traffic. Researching online, I’ve discovered numerous reports from other BMW owners experiencing the exact same failure on this model and other recent 3-series vehicles. This component failure is both common and costly, and yet there has been no recall or formal action from BMW to address it. Worse, the HMM is not covered under third-party powertrain warranties because it is considered an electronic part, leaving many owners with unsafe vehicles and no support. Given how widespread this issue appears to be — and the serious safety risk posed by sudden engine power loss — I urge the NHTSA to investigate this component for a potential recall or required manufacturer remedy.