NHTSA Complaint #11686115 — 2022 SUBARU FORESTER

I am writing to report a serious safety concern involving my '22 Subaru Forester, which is equipped with the Auto Start/Stop feature. This issue created a dangerous driving situation that could have resulted in severe injury or death to myself, my family, or other drivers on the road. While driving on the highway, our Forester's Auto Start/Stop system malfunctioned causing the engine to shut off completely while the vehicle. Specifically, the vehicle shut down in the left lane of traffic and failed to restart immediately leaving us unexpectedly immobile. Fortunately, my husband remained calm and immediately placed his foot back on the brake, placed the vehicle in park and restarted the vehicle manually by pressing the ignition button. However, had he hesitated during the confusion by not placing his foot back on the brake we could have been rear-ended, possibly by a large semi-truck which would have propelled us into the vehicle in front of us. Our dealer said the Auto Start/Stop system failing to restart the vehicle due to a weakening battery—for which there is no warning. The fact that a non-critical feature like fuel-saving Start/Stop is allowed to override the engine's operability based on battery voltage is deeply concerning. Batteries degrade over time. But a degraded battery should not be allowed to disable a moving vehicle.Having spoken directly with Subaru of America about this issue, they acknowledged and documented my case however I was told that it would be used as data for potential future action if other similar cases arise. In the meantime, no corrective action is being taken by Subaru, with me as an owner or proactively with the feature design.I respectfully urge the NHTSA to investigate this matter as a potential safety defect. The Auto Start/Stop system, as implemented in certainSubaru models (specifically the 2022 Forester in my case) may compromise safe vehicle operation when battery voltage drops below a certain threshold which is a safety flaw.