Steering controls BMW 540i 1998 E39 Workshop Manual

Downloaded from www.Manualslib.com manuals search engine
320-8
Steering and Wheel Alignment
4 MFL steering wheel: Loosen 2 airbag mounting fasteners
(Torx T27 or T30) located at rear of steering wheel (arrow).
4 Sport steering wheel:
Insert screwdriver through opening in rear of steering
wheel and push against spring tension to release
airbag.
Repeat procedure on other side of steering wheel.
- Carefully lift airbag from steering wheel and disconnect elec-
trical harnesses from
back side of unit. Refer to component
illustrations above. Also see
721 Airbag System (SRS).
Improper handling of the airbag could cause serious injury.
Store the
airbag with the horn pad facing up. If stored facing
down, accidental deployment couldpropel it violently into the
Avoid damaging the variety of convenience switches, such
as radio and cruise controls, installed in the steering wheel of
4 Remove steering wheel center bolt (arrow).

Downloaded from www.Manualslib.com manuals search engine
E39 brake system
BMW E39 models are equipped with vacuum power-assisted
four-wheel disc brakes with an integral
Antilock Brake System
(ABS). Single-piston calipers act on vented front and rear ro-
tors. A brake pad wear sensor for each axle indicates when
brake pads need replacement. The dual drum-type parking
brake system is integrated with the rear brake rotors.
Electronic braking and stability control
E39 models were introduced with Automatic Stability Control,
a computer controlled traction control system that uses the
AB5 system in conjunction with engine management controls
to control wheel spin during take-off and maintain vehicle sta-
bility while braking.
Added in the
1998 model year was Dynamic Stability Control
(DSC). This system implements wheel speed modulation
throughout all stages of driving. For example, DSC is able to
reduce understeer by applying differing amounts of braking
force to each wheel, or it can override the engine manage-
ment system during hard cornering.
A summary of distinguishing characteristics of the various
systems is shown in the table
E39 electronic braking and
stability control systems.
For ABS, ASC and DSC system and component descriptions,
see
300 Suspension, Steering and Brakes-General.
WARNING-
A car with electronic stability control is still subject to normal
physical laws. Avoid excessive speeds for the road conditions
encountered.
E39 electronic braking and stability control systems
Year (model)
manuf. up to 911998
(528i, 540i)
manuf. from 911999
(540i optional)*
From
911 999
(ail models) System
Automatic Stability Control (ASC) Identifiers
Electronic control module next to glove compartment
Hydraulic unit in right rear of engine compartment
No precharge pump
Dynamic Stability Control
(Bosch DSC
Ill v. 5.3)
Dynamic
Stabil~ty Control
(Bosch DSC
Ill v. 5.7) Electronic
control module next to glove compartment
Hydraulic unit in right rear of engine compartment
Precharge pump in left front of engine compartment, below steering
fluid reservoir
Separate rotational rate (yaw) and lateral acceleration sensors
Control
modulelhydraulic unit in right rear of engine compartment
No precharge pump
Combined rotational rate (yaw) and lateral acceleration sensors

Downloaded from www.Manualslib.com manuals search engine
1 Brakes
Max. machine limit per
friction ring side 0.8 mm (0.03
in) I
Brake rotor reconditioning specifications
Model
Replace
braite rotors in pairs
Bralre rotor sizes
Clean rotor with brake cleaner before installing.
Front
Model
6-cylinder
models (5251,
5281, 530i)
V-8 models (540i)
* When installing new rear brake rotors, adjust pariting brake
as described later, in Parking brake, adjusting. Rear
Vented rotor wear limit (min. thickness)
Tightening torques
Braite rotor to hub 16 Nm (12 ft-lb)
6-cylinder models
(525i, 5281, 530i)
- V-8 models (540i)
Front
296 mm (1 1.65 in)
324 mm (12.76 in)
Front bralte pad
carrler to steering ltnucitle 110 Nm (81 ft-lb)
Rear
298 mm (1 1.73 in)
Rear
brake pad carrier to wheel bearing carrier 65 Nm (48 ft-lb)
20.4
mm (0.80 in)
28.4 mm (1.12 in)
Road wheel to hub
120ilONm
(89 -t 7 it-lb)
18.4 mm (0.72 in)
The brake master cylinder is mounted to the front of the vacu-
um booster on the driverside bullthead.
-
CAUTION-
All E39 vehicles soldin the USA are equipped with Antilock
Braling System (ABS) and either Automatic Stability Control
(ASC) or Dynamic Stability Control (DSC).
In order for the
braling and stability controls to work properk if the brake
master cylinder is replaced, make sure that the brake system
is bled
by an authorized BMW dealer or other qualified repair
facility
using the BMW Service Tester. See Brake Bleeding
earlier
in this group.

Downloaded from www.Manualslib.com manuals search engine
1 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.
4 Rear sensor: Unscrew mounting bolt (arrows) in rear wheel
bearing carrier.
NOTE-
ABS wheelspeed sensor application may vary depending on
traction control system installed.

Downloaded from www.Manualslib.com manuals search engine
.
I Body-General 1
Rear wiper system
The rear wiper assembly on the E39 Sport Wagon is a self-
contained unit. The control electronics are integrated into the
gear drive that is part of the motor assembly. The control elec-
tronics contain two hall sensors, one
forthe park position and
one
forthe end stop or to signal reverse direction of the wiper
motor.
-
Wiperlwasher
stalk switch
/ 4 - 3
502400100
4 The rear wiper is controlled through the stalk switch on the
steering column. The switch includes the following functions:
Intermittent rear window wiping
Programmed rear window wiping interval
Operation of rear window washer
The wiper system automatically controls the following safety
and convenience features:
* Wiper interrupted when rear glass is opened
Wiper interrupted if wiper arm is blocked
Continuous wiping when vehicle is shifled into reverse
Antenna and sound system
4 There are two diversity FM antenna amplifiers:
FMI amplifier located in the rear window frame
FM2 / FZV amplifier located in the lefl D-pillar
The radio amplifier and CD changer are behind the side
ac-
cess panels in the cargo compartment:
CD changer on lefl side
Sound system subwoofer on right side
The subwoofer has a hold down knob and is mounted on a
hinge. It can be swung out to access
the batteryand fuse pan-
el by unscrewing the knob.

Downloaded from www.Manualslib.com manuals search engine
400-1 0
Body-General
Seats
4 Anatomically correct seats are constructed from polyure-
10 way seat adjustment thane foam
containing areas or "zones" of different firmness.
They offer good lateral support without constricting the occu-
pant.
The seats have a passive internal ventilation system: Cylin-
drical cavities within the cushions and backrests generate a
pumping effect as the ride motions cause occupant motion.
This
helps remove moisture and feeds fresh air into the seats.
Other features of the seating system:
The seat bases have steel springs for added support and
strength.
The seat control switches are along the outside edge of
the
seat.
Heated seats are an option in all models
In cars equipped with seat position memory, three different
seat confiaurations can be memorized by the seat control
module(s): Seat memory coordinates with outside mirror
memory. These functions are controlled by the seat mem-
ory
module(s).
* For security reasons, the release lever to fold the rear seat
backrest forward is installed in the trunk.
Sport Wagon models: Rear seat
baclts are split 60140, with
the center armrest on the left seat back.
The center armrest incorporates a non adjustable head-
rest. When folded down, the armrest opens out with
cup-
holders and a storage compartment. See 520 Seats for
more details.
instruments and controls
Everything in the interior passengercompartment essential to
the driver is logically grouped and easy to reach. All instru-
ments and controls have been arranged ergonomically and
are fully integrated into the overall design of the vehicle.
Tilt-telescopic steering wheel has
30 mm (1.2 in) of vertical
and longitudinal adjustment.
Multifunction steering wheel contains two
ltey pads con-
taining controls for the sound system, telephone and
cruise control.
Padded dashboard houses the instrument cluster and the
ventilation and heating system.

Downloaded from www.Manualslib.com manuals search engine
l Seats
This repair group covers removal and installation of the front
and rear seat.
SeatIMirrorlSteering Column Memory
< The basic features of seaffmirrorlsteering column operation,
including memory positions are integrated into the
ZKE Ill
system. Driver adjustment positions can be memorized and
stored for three different
users.The seat control module is in-
tegral with the seat and mirror switches. The seat control
module stores seat memory position via the "ripple" counter
module.
NOTE-
Passenger seat on sedan models uses a simple control cir-
cuit and do not include a memory module or on-board diag-
nostics.
Seat memory position, setting
With the transmission range selector in "P and the mirror
change over switched in the left position, switch the ignition
on and press the
"M" on the memory switch.
Press one of the three position switches
(1, 2 or 3) within
the
7 second memory period (memory indicator lamp will
illuminate for
7 seconds)
- The current positions of the mirrors, seat and steering col-
umn will now be stored in memory.
NOTE- Seat memory is held in an
EEPROM in the seat module and
is stored in memory before the
ZKE goes into its sleep mode.
If the battery is disconnected before the 16 minute sleep
mode activation, seat memorypositions are lost and repro-
gramming is required.
< Power seat controls.
A -Seat tilt
B - Longitudinal adjustment
C - Cushion height
D - Head restraint height
E - Back rest angle