Bmw X3 E83 2003 2004 2005 2006 Workshop Service Repair Pdf Manual
INTRODUCTION
Multiple restraint system 4 is a further development of the multiple restraint system (MRS) in the E46.
The MRS performs the following functions:
Detects an accident situation which could be critical for the occupants
Activates the necessary restraint systems (selectively, depending on the severity and type of accident)
New features, compared to the previous MRS (E46):
Bmw X3 E83 2003 2004 2005 2006 Workshop Service Repair Pdf Manual
2 airbag front sensors.
Front left door satellite and front right door satellite
Left-hand B-pillar satellite and right-hand B-pillar satellite with lateral and longitudinal acceleration.
Bmw X3 E83 2003 2004 2005 2006 Workshop Service Repair Pdf Manual
sensors
The MRS control unit interfaces have been expanded to 75 pins (50 pins in the E46).
Discontinuation of the MRS acceleration sensors under the front seats
The lateral acceleration sensors are now in the left and right-hand B-pillar satellites.
An advantage compared to the previous multiple restraint system is more precise airbag trigger control.
BRIEF DESCRIPTION OF COMPONENTS
The following sensors detect the direction and severity of an impact:
Airbag front sensors
The airbag front sensors are longitudinal acceleration sensors. The front airbag sensors detect a head-on
collision.
Front left door satellite and front right door satellite
There is a pressure sensor in each satellite door. The pressure sensors detect a side impact.
Left-hand B-pillar satellite and right-hand B-pillar satellite
The B-pillar satellites each contain a lateral acceleration sensor and a longitudinal acceleration sensor.
The sensors are arranged at 90 degrees to each other.
Acceleration sensors in the MRS control unit
There is a lateral acceleration sensor and a longitudinal acceleration sensor in the MRS control unit. The
sensors are arranged at 90 degrees to each other.