BMW 01 41 0 155 307 User Manual

Page of 203
175
n
Index
Data
Technology
Repairs
Car care
Controls
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 
530us133
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. 
390de330
Online Edition for Part No. 01 41 0 155 307 - © 09/00 BMW AG