BMW fault code 93C4

Crash safety module

In the crash safety module, code 93C4 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: Seat occupancy detector, front passenger: internal fault

Module versions: Crash safety module (ACSM2), Crash safety module (ACSM85)

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, Z4 (E85) 2006–2008, Z4 (E86) 2006–2008

MRS: Seat occupancy detector, front passenger: data memory full

Module version: Multiple restraint system (MRS5)

In: 1 Series (E87) 2004–2011, 1 Series (E81) 2007–2011, 1 Series (E82) 2007–2013, 3 Series (E90) 2005–2012, 3 Series (E91) 2005–2012, 3 Series (E92) 2006–2013, X1 (E84) 2009–2015

MRS: Seat occupancy detection, passenger - data memory full

Module version: Multiple restraint system (MRS7)

In: Z4 (E89) 2009–2016

No message (0x52) from center console control panel, SIM receiver, SZM transmitter

Module version: Safety and information module (SIM) (SGM_60_2)

In: 5 Series (E60) 2003–2010, 5 Series (E61) 2004–2010, 6 Series (E63) 2003–2010, 6 Series (E64) 2004–2010, 7 Series (E65) 2001–2008, 7 Series (E67) 2002–2008, 7 Series (E66) 2002–2008

SIM: Self test: transmission error

Module version: Safety and Information Module (SIM)

In: 7 Series (E65) 2001–2008, 7 Series (E66) 2002–2008, 7 Series (E67) 2002–2008

SIM: Self-test: transmission error

Module version: Safety and Information Module (SIM85)

In: Z4 (E85) 2002–2008, Z4 (E86) 2006–2008

Reading and clearing it

Fault code 93C4 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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