2021 Hyundai Sonata Hybrid electrical system problems

25 owner complaints filed with NHTSA name the electrical system on the 2021 Hyundai Sonata Hybrid — 47% of all complaints for this model year.

Electrical System complaints

47%

share of all complaints

—

median reported incident mileage

0 / 0

crash / fire reports

What owners report

“The vehicle experiences sudden, complete electrical power loss while driving at speed on highways and city streets or on the parking. All digital displays turn off, the engine shuts down, and power-assisted steering and braking are instantly lost without prior warning, presenting an extreme…”
filed Aug 5, 2026
“I purchased this vehicle pre-owned approximately two years ago and have since developed concerns about its reliability, particularly related to the electrical and hybrid systems. In hindsight, I suspect these issues may be part of the reason the original owner traded it in to a CarMax dealer…”
filed Jun 22, 2026
“The vehicle’s 12-volt electrical system repeatedly loses power within about 1 hour of sitting. The car becomes completely unresponsive (cannot unlock or start) and requires use of the built-in 12V battery reset button to restore power. This occurs frequently and makes the vehicle unreliable and potentially unsafe, as…”
filed May 22, 2026

Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.

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25-BE-002H TSB · Service Bulletin/Repair Instructions · issued May 16, 2025