Hyundai Elantra Hybrid 2020–2024 — technical service bulletin
Bulletin 25-01-010H DN · NHTSA communication 11014286 · issued Feb 11, 2025
Technical service bulletin
communication type
Fuel/propulsion System
component
2020–2024
model years
8
vehicle entries
Official summary
Certain Elantra hybrid (CN7 HEV), Sonata hybrid (DN8 HEV), and Tucson hybrid (NX4 HEV) vehicles may exhibit a warning light due to DTC Code P1BB20 (12V Lithium Battery Cell Voltage High). Follow the procedure in TSB 25-01-010H (or latest version) to perform the update the Battery management System (BMS) software.
Vehicles covered
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.