What does code P1851 mean on Audi vehicles?
The powertrain data bus is missing messages from the brake control module, disabling ABS/ESP functions.
OBD-II Code Audi
P1851 — Audi — Data-Bus Powertrain Missing Message from Brake Control Module
The powertrain data bus is missing messages from the brake control module, disabling ABS/ESP functions.
Common symptoms
- ABS/ESP inoperative
- warning lights
Possible causes
- CAN bus communication failure
- brake ECU offline
Initial recommendation
Perform brake system and CAN bus diagnostics, inspect wiring and control module status.
Safety notice
This information is for guidance only. Brand-specific codes may vary by model, year, engine, transmission and vehicle configuration. It does not replace a physical inspection or diagnosis by a qualified mechanic. If the vehicle is unsafe to operate, avoid driving it and seek professional inspection.
Analyze this code with MecaOBD
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