Abs Component Replacement; Wheel Speed Sensor. Replacing - BMW 5251 Service Manual

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Brakes
ABS COMPONENT REPLACEMENT
CA UTIOW-
If the tires on the car are of different makes, the ABS/trac-
tion controlsystem may overreact. Only fit tires of the same
make and treadpattern.
In adverse conditions, such as trying to rock the car out
of deep snow or other soft surface, or when snow
chains are fitted, it is advisable to switch off traction
control and allow tlie car driveline to operate conven-
tionally.
All E39 vehicles are equipped with Antilock Braking System
(ABS). Early production models featured ABS with Automatic
Stability Control (ABS
I
ASC). Later models came equipped
with ABS and Dynamic Stability Control (ABS / DSC). This
manual will refer to these systems as ABS. ASC or DSC will
be specified when necessary.
For ABS system and component descriptions, see 300 Sus-
pension, Steering and Brakes-General.
Wheel speed sensor, replacing
-
Raise applicable end of car.
Make sure that the car is firmly supported on jack stands de-
signed for the purpose. Place jack stands beneath structural
chassis points. Do not place jack stands under suspension
<
Front sensor: Unscrew mounting bolts (arrows) at steering
knuckle.
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Rear sensor: Unscrew mounting bolt (arrows) in rear wheel
bearing carrier.
NOTE-
ABS wheelspeed sensor application may vary depending on
traction control system installed.