Service bulletin LI54.21-P-078926
A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.
| Type | Service bulletin |
|---|---|
| NHTSA id | 11021897 |
| Published by NHTSA | 2025-08-15 |
| Manufacturer's number | LI54.21-P-078926 |
| Manufacturer's date | 2025-08-04 |
| NHTSA component | ENGINE |
NHTSA's summary
Complaint: Check engine light comes on when driving/starting the vehicle. No drivability concerns. Cause: Communication error in G1/3 - 48 V on-board electrical system battery (48 V LIB) or N127 - 'Drivetrain' control unit (PTCU)saved and/or current Remedy: Update the software for the control unit G1/3 - 48 V on-board electrical system battery (48 V LIB) : --> Remedy-SW A001902042425/12 If the fault profile still occurs with the installed software, check the wiring and the plug contacts: UG1/3 - 48 V on-board electrical system battery (48 V LIB) N83/1 - DC/DC converter (DDW) N127 - 'Drivetrain' (PTCU) control unit NOTE: Replacing parts does not remedy the problem.
The document
The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.
Components
Engine
| MERCEDES-BENZ AMG CLA35 | 2020 to 2024 |
|---|---|
| MERCEDES-BENZ AMG CLA45 | 2020 to 2024 |
| MERCEDES-BENZ AMG GLA45 | 2021 to 2023 |
| MERCEDES-BENZ AMG GLB35 | 2021 to 2025 |
| MERCEDES-BENZ CLA 250 | 2020 to 2025 |
| MERCEDES-BENZ GLA 250 | 2021 to 2025 |
| MERCEDES-BENZ GLA 250 4MATIC | 2024 |
| MERCEDES-BENZ GLB 250 | 2020 to 2025 |
Listing a model year does not mean every vehicle of it is concerned: the document says which.