E39 Electronic Brake And Stability Control Systems Application Table; Abs System; Automatic Stability Control (Asc) - BMW 5251 Service Manual

300-1 2
I
Sus~ension, Steerincl and Brakes
-
General
E39 electronic brake and stability control
systems application table
(528i,
54bi)
Traction (ASC)
I
Hydraulic unit in right rear of engine compartment
1
Identifiers
Year (model)
I
No precharge pump
1
Manuf. up to 911998
l~utomatic Stability Control plus
I
Electronic control module next to glove compartment
System
Precharge pump in lefl front of engine compartment, below
steering fluid reservoir
Separate rotational rate (yaw) and lateral acceleration sensors
I
I
Combined rotational rate (yaw) and lateral acceleration sensors
Electronic control module next to glove compartment
Hydraulic unit in right rear of engine compartment
Manuf. up to 911999
(540i optional)
I
I
ABS system
Dynamic Stability Control (Bosch
DSC Ill
v.
5.3)
The electronically controlled ABS maintains vehicle stability
and control during emergency braking by preventing wheel
lock-up.
ABS
provides optimum deceleration and stability dur-
ing adverse conditions. It automatically adjusts brake system
hydraulic pressure at each wheel to prevent wheel lock-up.
Control moduleihydraulic unit
in
right rear of engine compartment
No precharge pump
Manuf. from 911999
(all models)
Automatic Stability Control (ASC)
Dynamic Stability Control (Boscli
DSC
Ill
v. 5.7)
NOJE-
ASC (Automatic Stability Control) may also be referred to as
A S C i T (Automatic Stability ControkTraction).
A S C works in conjunction with ABS and the engine manage-
ment system to enhance vehicle control. The main function of
the A S C system is to maintain the contact between the tires
and the road surface under all driving conditions. This is
achieved through exact application and management of brak-
ing and drivetrain forces.
The A S C system improves traction by electronically applying
the rear brakes when the rear drive wheels are spinning at a
faster rate than the front wheels. The combined ABSIASC
control module, operating through the ABS hydraulic control
unit, modulates braking force at the rear wheels.
In addition, A S C overrides the throttle opening to reduce en-
gine torque and maintain vehicle traction. Because the throt-
tle is controlled electronically, the driver cannot increase
engine power output during ASC
intervention regardless of
how far the accelerator pedal is pushed.