Audi q7 2017, Manual, Page: 14 / 70

10
Safety belts
Front automatic belt retractor
With Audi pre sense basic, the front automatic belt retrac-
tors are equipped with pyrotechnic belt tensioners, active
belt force limiters and with reversible safety belt tensioners
with electric motors.
Left and Right Front Seat Belt Tensioner Control Modules
J854 and J855 communicate with Airbag Control Module
J234 over a sub-bus system. J854 and J855 have no “intelli-
gence but are actuators of the airbag control module.
When Audi pre-sense basic detects specific driving situa-
tions, corresponding signals are placed on the data bus.
The airbag control module evaluates these signals and if
necessary instructs J854 and J855 to partially or fully
tension the safety belts.
The Q7 uses ball-type pyrotechnic safety belt retractors. It
is NOT necessary to perform a Basic Setting Test Plan if the
belt is replaced.
637_085
Outer automatic seat belt retractors for the 2nd and 3rd seat rows
The automatic seat belt retractors of the 2nd and 3rd seat
rows are equipped with pyrotechnic belt tensioners. The automatic seat belt retractors use pyrotechnic push rod
tensioners.
637_087
Automatic seat belt
retractor 3rd seat row
Reversible belt tensioner
with electric motor
Pyrotechnic safety
belt tensioner
Active belt force limiter
Automatic seat belt
retractor 2nd seat row