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Home >> BMW >> 2004 >> 745Li >> Repair and Diagnosis >> Restraints >> Restraints Control Systems >> Intelligent Safety Integration System - Overview >> Intelligent Safety Integration System (ISIS) >> System Overview >> A-Pillar Satellite, Left And Right (SASL/SASR)
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A-Pillar Satellite, Left And Right (SASL/SASR)

The satellites of the A-pillar left/right are virtually identical.

The satellites are installed to the left and right under the A-pillar trim panel in the footwell.

The A-pillar satellites have integrated transverse (side impact) and longitudinal (front or rear impact) sensors.

The SASL is responsible for deploying the Advanced Head Protection airbags (AHPS I/II) and the drivers side knee airbag.

Fig 1: Identifying A-Pillar Satellite, Left And Right (SASL/SASR)
G03391522Courtesy of BMW OF NORTH AMERICA, INC.

The SASR is responsible for deploying the passenger airbag, the AHPSI/II and the passenger knee airbag.

The A-pillar satellites are connected to the SIM via the byteflight.  The power supply of the satellites is also from the SIM and it is buffered by the memory backup capacitor.

In sleep mode of the byteflight  , the power supply of the SASL/SASR is deactivated by the SIM. The watchdog function is run by the SIM.

Fig 2: A-Pillar Satellite, Left And Right (SASL/SASR) Circuit Diagram
G03391523Courtesy of BMW OF NORTH AMERICA, INC.