Mercedes-Benz AMG CLA35 2020–2025 — technical service bulletin
Bulletin LI54.21-P-078926 · NHTSA communication 11021149 · issued Aug 1, 2025
Technical service bulletin
communication type
Electrical System
component
2020–2025
model years
39
vehicle entries
Official summary
Complaint Check engine light comes on when driving/starting the vehicle. No drivability concerns. Cause SW conflict of the 48V battery Remedy Update the 48V battery to SW 25/12 A0019020424
Vehicles covered
- 2020 Mercedes-Benz AMG CLA35
- 2021 Mercedes-Benz AMG CLA35
- 2022 Mercedes-Benz AMG CLA35
- 2023 Mercedes-Benz AMG CLA35
- 2024 Mercedes-Benz AMG CLA35
- 2020 Mercedes-Benz AMG CLA45
- 2021 Mercedes-Benz AMG CLA45
- 2022 Mercedes-Benz AMG CLA45
- 2023 Mercedes-Benz AMG CLA45
- 2024 Mercedes-Benz AMG GLA 35
- 2025 Mercedes-Benz AMG GLA 35
- 2021 Mercedes-Benz AMG GLA35
- 2022 Mercedes-Benz AMG GLA35
- 2023 Mercedes-Benz AMG GLA35
- 2021 Mercedes-Benz AMG GLA45
- 2022 Mercedes-Benz AMG GLA45
- 2023 Mercedes-Benz AMG GLA45
- 2021 Mercedes-Benz AMG GLB35
- 2022 Mercedes-Benz AMG GLB35
- 2023 Mercedes-Benz AMG GLB35
- 2024 Mercedes-Benz AMG GLB35
- 2025 Mercedes-Benz AMG GLB35
- 2020 Mercedes-Benz CLA 250
- 2021 Mercedes-Benz CLA 250
- 2022 Mercedes-Benz CLA 250
- 2023 Mercedes-Benz CLA 250
- 2024 Mercedes-Benz CLA 250
- 2025 Mercedes-Benz CLA 250
- 2021 Mercedes-Benz GLA 250
- 2022 Mercedes-Benz GLA 250
- 2023 Mercedes-Benz GLA 250
- 2024 Mercedes-Benz GLA 250
- 2025 Mercedes-Benz GLA 250
- 2020 Mercedes-Benz GLB 250
- 2021 Mercedes-Benz GLB 250
- 2022 Mercedes-Benz GLB 250
- 2023 Mercedes-Benz GLB 250
- 2024 Mercedes-Benz GLB 250
- 2025 Mercedes-Benz GLB 250
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.