Hyundai Elantra Hybrid 2020–2023 — technical service bulletin
Bulletin SERVICE CAMPAIGN 9B4 · NHTSA communication 11006055 · issued Jul 4, 2024
Technical service bulletin
communication type
Electrical System
component
2020–2023
model years
7
vehicle entries
Official summary
This bulletin provides the procedure to update the software for the Battery Management System (BMS) on certain Elantra Hybrid (CN7 HEV), Sonata Hybrid (DN8 HEV), and Tucson Hybrid (NX4 HEV) vehicles that may exhibit a warning light with DTC P1BB20.
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.