Airbags - BMW 5251 Service Manual

400-8
Body-General
Airbags
Front airbags, s~de a~rbags, pyrotechnic seat belt tensioners
and the Battery Safety Terminal (BST) are integrated into the
Supplemental Restraint System (SRS) and its variants.
NOTE-
The BMW SRS system is called Multiple Restra~nt System
(MRS). Over the years,
E39
cars were equipped with MRS,
MRS 1 1 , MRS 1 1 1 . Each version offers varied features and im-
provements over the previous system.
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As many as 8 airbags may be installed in E39 cars, depend-
ing on model and MRS version.
The front airbags operate without sodium azide propellant,
widely considered an irritant when an airbag is deployed.
Starting with 1999 models. "smart"front passenger and driver
airbags were installed. These are of the dual-threshold, dual
stage design, including a sensorto help prevent the unneces-
sary deployment of the passenger side airbag if the seat is un-
occupied.
MRS control
Depend~ng on options chosen, one airbag may be installed in
module
each door of the sedan and Sport Wagon models, protecting
passengers against s ~ d e impacts.
Head Protection System (ITS) airbags strelch diagonally
across the tops of the front doors.
Airbag deployment automatically triggers fuel shutoff, turns
on the hazard and interior lights, and unlocks the doors.
- -
WARNING
-
Airbags are inflated by an explosive device. Handled im-
properly or without adequate safeguards, airbag units can
be very dangerous. Special precautions must be observed
prior to any worlc at or near any of the airbags. See 721 Air-
bag System (SRS).
Always disconnect the battery and cover the negative
(-) battery terminal with an insulator before starting di-
agnostic, troubleshooting or service work on cars fitted
with SRS, and before doing any welding on the car.