Subaru Faces Class Action Lawsuit Over Widespread Battery Drain Issues in Multiple Models

Owners of several Subaru models are accusing the automaker of shipping vehicles with a systemic battery drain issue that persists even when the cars are parked and the ignition is off. The allegations, detailed in a newly filed class action lawsuit, claim that faulty electrical systems continue to draw power from replacement batteries, leaving vehicles dead overnight or inoperable during operation.

Lawsuit Details and Affected Models

The complaint was filed on May 1, 2025, in the U.S. District Court for the District of New Jersey. It names both Subaru of America and Subaru Corporation as defendants. Plaintiffs argue that the vehicles’ electrical systems fail to enter a proper low-power sleep mode after shutdown, creating a constant parasitic draw that slowly drains the battery.

The lawsuit lists the following affected Subaru models and model years:

• 2021–2022 Subaru Outback
• 2021–2024 Subaru Forester
• 2021–2023 Subaru Legacy
• 2021–2023 Subaru WRX
• 2021–2022 Subaru Ascent
• 2019–2023 Subaru Crosstrek
• 2019–2024 Subaru Crosstrek Hybrid
• 2022–2025 Subaru Forester Wilderness
• 2019–2023 Subaru Impreza

Reported Issues and Plaintiff Experiences

According to the lawsuit, owners have reported a range of severe issues, including:

• Repeated no-start conditions, leaving vehicles inoperable
• Vehicles stalling in traffic, creating hazardous situations
• One plaintiff’s 2024 Outback allegedly shutting down completely while driving, blocking traffic and requiring a tow
• Dealerships replacing batteries only for the same problems to recur months later

The suit does not allege that Subaru installed weak batteries. Instead, plaintiffs claim the core issue is the vehicles’ electronics failing to enter a proper low-power sleep mode after the engine is turned off. This allegedly results in a constant parasitic draw that slowly drains the battery, even when the car is parked and unused.

Subaru’s Internal Investigations and Technical Bulletins

The filing references several Subaru technical service bulletins related to parasitic battery diagnostics. Notably, an October 2025 bulletin reportedly instructed technicians not to automatically blame the vehicle’s Data Communication Module (DCM) for parasitic draw issues. The bulletin noted that newer-generation DCMs did not show consistent parasitic draw problems, suggesting Subaru was aware of the issue internally while owners continued to report dead batteries and repeated jump-starts.

Modern Cars and Power Consumption: A Growing Concern

Modern vehicles are increasingly power-hungry due to the integration of advanced features such as connected services, infotainment systems, and driver-assistance technologies. Many of these features remain in an always-on state, even when the vehicle is parked. While increased power consumption is expected, the lawsuit argues that persistent and unaddressed parasitic draw is not acceptable and constitutes a defect.

Subaru has not yet publicly responded to the allegations. The outcome of the lawsuit remains pending as both parties prepare for further legal proceedings.