BMW fault code C94B

Crash safety module

In the crash safety module, code C94B means different things depending on the version of the module in the car. Find your car below; the app shows the right one for yours.

ACSM: F-CAN communication fault

Module version: Crash safety module (ACSM2)

In: 1 Series (E82) 2007–2013, 1 Series (E88) 2008–2013, 3 Series (E92) 2006–2013, 3 Series (E93) 2007–2013, X1 (E84) 2009–2015, X5 (E70) 2006–2013, X6 (E71) 2008–2014, X6 (E72) 2009–2011

MRS: F-CAN communication fault

Module version: Multiple restraint system (MRS7)

In: Z4 (E89) 2009–2016

Reading and clearing it

Fault code C94B is a BMW code, stored in the car's crash safety module, not a generic OBD2 code (P0xxx): a generic OBD2 reader only reaches the engine's emissions faults, so it won't show it. AutoLingo for BMW reads it with BMW's own diagnostic protocols, in plain English, with the details the module stored about it, and clears it after a repair. If a fault comes right back after it's cleared, the problem is still there.

The crash safety module is on: 5 Series (E60), 5 Series (E61), 6 Series (E63), 6 Series (E64), 7 Series (E65), 7 Series (E66), 7 Series (E67), X5 (E70), X6 (E71), X6 (E72), 1 Series (E81), 1 Series (E82), X1 (E84), Z4 (E85), Z4 (E86), 1 Series (E87), 1 Series (E88), Z4 (E89), 3 Series (E90), 3 Series (E91), 3 Series (E92), 3 Series (E93)

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