MRS III Operation

MRS III OPERATION

As with previous Systems, the triggering thresholds are programmed in the MRS III control module. These thresholds are determined by BMW through crash and vehicle testing during the design and development of the vehicle. These thresholds will vary depending on the vehicle size and design.

There are several different thresholds for airbag and safety restraint deployment including;
- Belt pre-tensioner threshold for activation of the seat belt tensioners.
- Airbag threshold # 1 - the first level of activation for the two stage front airbags, always deployed first when the front triggering threshold is reached.
- Airbag threshold # 2 - the second level of the two stage front airbags, can be deployed simultaneously or after a time delay, depending on the severity of the impact.
- Rear crash threshold - for activation of the seatbelt tensioners with a rear impact.
- Battery safety terminal threshold - for activation of the BST with airbag deployment.
- Side airbag/ITS threshold - for deployment of the side and thorax airbags.

TRIGGERING THRESHOLDS - TWO STAGE AIRBAGS
The programming of the MRS III includes four triggering thresholds for the two stage front airbags. The triggering of the front airbags is also dependent on whether the seat belts are connected and if the front passenger seat is occupied. The triggering thresholds for the two stage airbags are as follows:







If the signal from the SBE is defective on triggering, the MRS III will deploy as if the seat is occupied

If the signal from the seat belt contacts are defective, the MRS III will deploy as if the belts were not buckled.