Four-wheel drive, Safety belt tensioner, Four-wheel drive safety belt tensioner – BMW 01 41 0 155 307 User Manual
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Overview
Four-wheel drive
Safety belt tensioner
The transmission of power to the four
drive wheels is provided permanently
through a transfer box. The distribution
of torque between the front and rear
axles is 38 % to 62%.
Traditional differential locks at the front
and rear axles and in the transfer box
are not required. Their function is
assumed by automatic braking inter-
vention at all four wheels. These trac-
tion interventions are governed by
Automatic Differential Brake (ADB-X), a
sub-function of DSC.
If a wheel tends to slip, it is braked
automatically by ADB-X until it once
again gains traction, and drive force
can be transmitted to that wheel. In
addition, the drive force is distributed to
the remaining wheels during this
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system intervention. Engine output is
also reduced if necessary.
When the DSC is deactivated, the
ADB-X traction intervention is set for
the maximum drive force. However, the
engine intervention and the stability
controls are no longer available. For
this reason, DSC should only be deacti-
vated in the exceptional circumstances
described on page
The BMW 325xi is not an off-road
vehicle. Instead, permanent four-wheel
drive provides a high degree of vehicle
stability and tractive ability under all
road conditions, and will aid you in crit-
ical driving situations, e. g. driving in
extreme winter conditions or on loose
road surfaces.
The safety belt tensioner responds to
severe frontal collisions by tightening
the belts to ensure that occupants
remain firmly positioned in their seats.
A gas-pressure system retracts the
buckle assembly to tension the
shoulder and lap belts within fractions
of a second. This reduces the tendency
to slide under the lap belt.
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Online Edition for Part No. 01 41 0 155 307 - © 09/00 BMW AG