B129C on the 2017 Mercedes-Benz AMG GT
The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.
This code is specific to a manufacturer and is not described here. Its meaning is in the manufacturer's service information.
| LI82.85-P-076800 | 2023-11-03. Service bulletin. The "SOS nonfunctional" message appears sporadically in the instrument cluster of the vehicle. The fault code B129C00 is stored in the control unit log. The message occurs in particular after the vehicle has been non-operational for an extended period of time; the message then disappears of its own accord after a few minutes. No functional limitation to the emergency call system is to be expected. Software error in N112/9 control unit for telematics services (HERMES). Software update for control unit N112/9 - Control unit for telematics services (HERMES) to software release E522.8. If, against expectations, the erroneous display of the message in the instrument cluster continues to occur following the update, please create a TIPS case. |
|---|
1 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.