Kia Niro 2023–2024 — technical service bulletin
Bulletin SC335_TSB_CLSD · NHTSA communication 11019891 · issued Jun 26, 2025
Technical service bulletin
communication type
Electrical System
component
2023–2024
model years
4
vehicle entries
Official summary
TECHNICAL SERVICE BULLETIN: VOLUNTARY SERVICE CAMPAIGN: BMS S/W LOGIC IMPROVEMENT FOR DTC P1BB2 (SC335) CLOSED AND SUPERSEDED TO SC338 (TSB) - This bulletin is now closed. "This bulletin provided information to upgrade the Battery Management System ‘BMS’ software logic on certain 2023-2024MY Sportage HEV (NQ5 HEV) vehicles produced from February 15, 2022 to October 28, 2023, and2023-2024MY Niro HEV (SG2 HEV) vehicles produced from June 21, 2022 through February 6, 2023. Due to a software issue, the Battery Management System (BMS) may inadvertently overcharge the 12V Lithium battery.
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.