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MRS III Introduction




MULTIPLE RESTRAINT SYSTEM (MRS III)

INTRODUCTION

The X5 is equipped with the Multiple Restraint System (MRS Ill) which employs the use of "SMART" technology Smart technology refers to the control module's programming which allows for the deployment of the airbags, in stages, depending on the severity of the impact. Two stage airbags are used for both the driver and front passenger which allows for a softer cushioning effect when the bags are triggered at lighter impacts.

The MRS III system is installed in E38/E39 and E46 Sedan vehicles as of 3/99 production and in E46 Coupes as of 6/99 production.

MRS III control modules are manufactured by either Bosch or Temic. While the functional operation of both modules are the same. The control modules are not interchangeable from a replacement standpoint. Always refer to the EPC parts system to ensure that the proper module is installed in the vehicle.

In addition to the use of two stage airbags for the driver and passenger, the following features are also included in the MRS III system:
- The MRS III control module is linked to the K-Bus for coding and diagnosis.
- The MRS III includes a fuel pump cut off feature in the event of an airbag deployment.
- Inert gas generators are now used for all air bags and seat belt tensioners. The inert gas is a mixture of hydrogen (13.5%) and oxygen (86.5%).