brake BMW 525I 2004 User Guide

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The current driving speed is stored as a
desired speed and briefly displayed in the
instrument cluster, see below.
1 Desired speed store and increase
Press the lever forward:
The system adopts and stores your current
speed as a desired speed. The speedome-
ter indicates this speed.
Subsequently pressing forward increases
the desired speed to the next 5-mile place/
10 km/h.
Each time the lever is pressed forward
again, the desired speed is increased by
another 5 mph/10 km/h until a maximum of
110 mph/180 km/h is reached. The speed
then displayed is stored and reached on a
clear road.
If the system cannot be activated, the
display ACC --- mph/km/h briefly
appears in the instrument cluster. The sys-
tem may have been automatically deacti-
vated, refer to Deactivate system, or a mal-
function has occurred.
To call up Check Control messages, refer
to page 68.<
2 Desired speed store and decrease
Pull back the lever:
The current driving speed is rounded off to
the next 5-mile place/10 km/h, displayed
and stored.
Each time the lever is pulled back again,
the desired speed is decreased by another
5 mph/10 km/h until the minimum speed of
20 mph/30 km/h is reached. The speed
then displayed is stored and reached on a
clear road.
3 Deactivate system
Press the lever up or down while the sys-
tem is active. The displays in the instrument
cluster disappear. You can use the system
again as required.
In addition, the system is deactivated auto-
matically:
>When you apply pressure to the brake
pedal
>When you select the automatic trans-
mission's/SMG's neutral range N
>With the manual transmission idling
>When you deactivate the DSC Dynamic
Stability Control
>When you actuate the parking brake
during driving
>When the system reduces the speed to
below 20 mph/30 km/h due to a traffic
situation.
The system deactivates automatically
when the speed is set to below
20 mph/30 km/h. A gong sounds and a
message appears on the Control Display.
The active intervention of the driver is
required.<
When you switch off the ignition, the stored
desired speed is deleted.
4 Resume to stored desired speed
and distance setting
Press button 4:
The displays appear in the instrument clus-
ter. The system is reactivated and uses the
last stored desired speed and distance set-
ting.
4 Fine adjustment of desired speed
In the activated state, the desired speed
increases by 1 mph/1 km/h each time
button 4 is pressed briefly.

Driving
62
5 Select distance
You can choose from four distance steps.
>Rotary switch downward:
Decrease distance.
>Rotary switch upward:
Increase distance.
The selected distance is displayed in the
instrument cluster. Distance 1
Distance 2
Distance 3
This distance is always set
when the system is used for the
first time after starting the
engine.
Distance 4
Use good judgment to select the
appropriate following distance given
road conditions, traffic, applicable laws
and driving recommendations for safe fol-
lowing distance.<
Things to know about active cruise control
As with conventional cruise control
systems, active cruise control in no
way diminishes or substitutes for the
driverÕs own personal responsibility, alert-
ness and awareness in adjusting speed,
braking or otherwise controlling the vehi-
cle. The driver should decide when to use
the system on the basis of road, traffic, vis-
ibility, and weather conditions. Active
cruise control is intended for use on high-
way-type roadways where traffic is moving
relatively smoothly. Do not use this system
in city driving; heavy traffic such as during rush hour; on curvy, winding roads, slip-
pery roads or roads with sharp curves such
as highway off-ramps; during inclement
weather such as snow, strong rain or fog;
or when entering interchanges, service/
parking areas or toll booths. It is also
important to regulate your vehicle's speed
and distance setting within applicable legal
limits. Always be ready to take action or
apply the brakes if necessary, especially
when the system is actively following a
vehicle in front of you.<

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Always remember that the range and
ability of the system does have phys-
ical limitations. It will not apply the brakes
or decelerate your vehicle when there is a
slow-moving vehicle, stopped vehicle or
stationary object ahead of you, as for
example, at a traffic light or a parked vehi-
cle. Also, the system does not react to
oncoming traffic, pedestrians or other type
of potential traffic such as a rider on horse-
back. It is also possible that the system
may not detect smaller moving objects
such as motorcycles or bicycles. Be espe-
cially alert when encountering any of these
situations as the system will neither auto-
matically brake, nor provide a warning to
you. Also, be aware that every decrease in
the distance setting allows your vehicle to
come closer to a vehicle in front of you and
requires a heightened amount of alert-
ness.<
If while your vehicle is actively following a
vehicle in front of you and the vehicle
ahead speeds up or the lane ahead
becomes clear, then your vehicle will
accelerate to the speed you have selected.
Be aware that changing to a clear, unob-
structed lane will also result in your vehicle
accelerating.
Be certain to deactivate the system
when you pull into an exit lane for a
highway off-ramp.<
Also, vehicles traveling in a staggered man-
ner on a highway may cause a delay in the
system's reaction to a vehicle in front of
you or may cause the system to react to a
vehicle actually in the lane next to you.
Always be ready to take action or apply the
brakes if necessary.
Active cruise control can only decelerate
the vehicle to approx. 20 mph/30 km/h. If
the system reduces vehicle speed below
20 mph/30 km/h or if DSC/ABS is engaged
while driving, the system will automatically
deactivate.
Remember, the system cannot stop
your vehicle. In addition, the system is
deactivated whenever the driver applies
the vehicle brakes, shifts the transmission
from drive/D to neutral/N, or deactivates DSC. After any deactivation, the system
will no longer automatically activate the
vehicle brakes, which means the driver
must intervene and resume manual brak-
ing. You should then reactivate the system
only when you are fully aware of the prior
speed and distance settings.<
Active cruise control may brake when you
reduce the stored desired speed; however,
the driver must constantly monitor traffic
and intervene if necessary.
When you switch off the engine or ignition,
active cruise control is fully switched off,
too, and any settings you have selected are
canceled.
Behavior in curves
Because of the limited range of the system,
it is possible that in curves or on the peaks
and valleys of hilly roads, a vehicle ahead
may be recognized late, or not at all. There-
fore, it is up to the driver to select a speed
that is prudent in view of the curves and
terrain of the roadway.
In approaching a curve, it is possible that
active cruise control would react briefly to a
vehicle in the adjacent lane. In addition, the
system can sense if your vehicle is in a
curve and may not accelerate. If your vehi-
cle decelerates in either case, you can

Driving
64 choose to overcome the deceleration by
briefly pressing the accelerator pedal.
Driver interventions
Anytime the driver presses down on
the accelerator pedal, any automatic
braking action by the system is interrupted
until the pedal is fully released. After doing
this, release the accelerator and the system
again controls your cruising speed and dis-
tance setting. While driving with activated
system, resting your foot on the accelerator
pedal will cause the system not to brake
even if necessary. Be certain that floormats
or other objects on the vehicle floor do not
interfere with movement of the accelerator
pedal.<
While active cruise control is capable
of braking your vehicle automatically
when you approach a slower vehicle
ahead, it is important to be aware that the
ability of the system to apply the brakes is
also limited, if you are driving down a steep
grade or when you reduce your desired
speed sharply. The system cannot stop
your vehicle. It uses only a portion of brak-
ing system capacity and does not utilize the
full capacity of the vehicle braking system.
Therefore, the system cannot decrease
your speed for large differences in speed
between your vehicle and the vehicle
ahead. Examples: during emergency brak-
ing, when you approach a vehicle traveling
at a much lower speed than your own
speed such as approaching a toll booth or
when a much slower vehicle cuts in front of
you at close range.<
Whenever active cruise control
recognizes a situation that
requires driver braking because
the system capacity has been
reached or has been exceeded,
the system alerts the driver by flashing this
symbol in the instrument cluster and
sounding a signal.
Swerving vehicles
When a vehicle moves from an adjacent
lane into your lane, active cruise control will
not recognize this vehicle until it is fully in
your lane ahead of your vehicle.
Malfunctions
If there is a malfunction, the indica-
tor lamp symbol is displayed in the
instrument cluster. Please note any
supplementary information that appears on
the Control Display.
The build-up of foreign material, e.g.,
snow, ice, dirt, road debris, etc., can lead
to reduced detection performance of active
cruise control. You should check the sen-
sor under the front bumper and clean it as
necessary prior to driving your vehicle. If
the sensor becomes covered by foreign
material or has a malfunction, it is possible
that the sensor will no longer be able to
detect vehicles in front of you. After the
system recognizes that the sensor is no
longer functional, a message is displayed
on the Control Display and an acoustic sig-
nal is emitted.

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ence of objects in green before they are
close enough to generate a signal tone.
Control Center, for principle details, refer to
page 16:
1.Open the start menu by pressing the
button
2.Open the menu by pressing the con-
troller
3.Select "Vehicle settings" and press the
controller
4.Select "PDC" and press the controller
5.Select "Monitor display on" and press
the controller.
is displayed with the PDC image
switched on.
The display then appears on the Control
Display as soon as PDC is automatically
activated.
The previous display automatically reap-
pears after the system is deactivated.
Limits of the system
Even with PDC, final responsibility for
estimating the distance between the
vehicle and any obstructions always
remains with the driver. Even when sensors are involved, there is a blind spot in which
objects cannot be detected. The system is
also subject to the physical limits that apply
to all forms of ultrasonic measurement,
such as those encountered with thin and
wedge-shaped objects, etc. Low objects
already displayed, e.g. a curb, can also dis-
appear from the detection area of the sen-
sors again before a continuous tone
sounds.
Loud noises from outside and inside your
vehicle may prevent you from hearing the
PDC signal tone.<
Keep the sensors clean and free of ice
or snow in order to ensure that they
will continue to operate effectively.
Do not apply high pressure spray to the
sensors for a prolonged period of time.
Keep the spray at least 4 in/10 cm away
from the sensors.<
Driving stability control/
ABS Antilock Brake System
Your BMW is equipped with an extended
array of systems designed to enhance and
maintain vehicle stability under extreme
conditions. The following section describes
these functions based on ABS and DSC.
The concept
ABS enhances active safety by preventing
the wheels from locking under braking.
The ABS is operational every time you start
the engine. ABS includes the functions
CBC Cornering Brake Control and EBV
Electronic Brake Force Distribution.
In case of malfunction
If the indicator lamp lights up in yel-
low, this indicates that ABS has
been deactivated in response to a
system malfunction. Conventional braking
efficiency remains available without limita-
tions. Please have the system inspected at
your BMW center.

Technology for comfort, convenience and safety
78
CBC Cornering Brake Control
CBC is a supplement to ABS. It provides
further enhancements in vehicle stability
and steering response during lane changes
and cornering at high rates of lateral accel-
eration.
EBV Electronic Brake Force
Distribution
EBV controls the brake system's applica-
tion pressure at the rear wheels to ensure
stable deceleration.
In case of malfunction
If the brake system warning lamp
lights up in red, appearing together
with the yellow indicator lamps for
ABS and DSC:
The driving stability control has
failed.
If all three lamps light up yellow:
Fault in the driving stability control.
The EBV electronic brake-force distribution
is active.
While you may continue, you should
remember to proceed cautiously and drive
defensively while avoiding full brake appli-
cations.
Please have the system checked at the
nearest BMW center.
If a message appears on the Control Dis-
play, please note the supplementary infor-
mation.
You can find more information on the
Check Control starting on page 68.
Indicator and warning lamps for
Canadian models.
Driving stability control/
DSC Dynamic Stability
Control
The concept
DSC maintains vehicle stability, even in
critical driving situations.
The DSC is operational every time you start
the engine. DSC includes the functionality
of the DTC Dynamic Traction Control and
DBC Dynamic Brake Control, refer to
page 79.
The system optimizes vehicle stability dur-
ing acceleration and when starting from a
full stop, as well as optimizing traction. The
system recognizes any tendency for the
vehicle to assume an unstable attitude
such as oversteer or understeer; it then
counteracts this tendency with a combina-
tion of graduated reductions in engine
torque and selective braking intervention at
individual wheels. DSC provides optimal
stability within the limits defined by the
laws of physics.
Indicator lamps
The indicator lamp in the instrument
cluster goes out soon after you start
the engine.
If the indicator lamp flashes:
DSC is regulating the drive and braking
forces.
If the indicator lamp lights up permanently:
DSC has been switched off using the but-
ton.
If the indicator lamp and the brake
warning lamp light up permanently:
Malfunction in DSC, DTC and DBC.
When the system is off, the stability main-
tenance functions described above are no
longer available. The vehicle will remain
completely operational, however, without
DSC.
Please respond to any malfunctions by
referring the problem to your BMW center.

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Indicator and warning lamps for
Canadian models.
DTC Dynamic Traction Control
In special driving states, e.g. in deep snow,
DTC ensures maximum forward momen-
tum. The gain in forward momentum also
involves a reduction in driving stability.
DTC is active up to 45 mph/70 km/h.
Activating DTC
Press the DSC button briefly; the
DTC indicator lamp in the instru-
ment cluster lights up permanently.
You may find it useful to briefly activate
DTC under the following special circum-
stances:
>When rocking the vehicle and starting
off in deep snow or on loose road sur-
faces
>When ascending snow-covered hills,
and when driving in deep or on hard-
packed snow
>When driving with snow chains.
When DTC is active, DSC provides
only limited system response up to a
speed of approx. 45 mph/70 km/h. Control
intervention for stability-enhancement is
reduced.<
Deactivating DTC again
Press the DSC button again; the DTC indi-
cator lamp in the instrument cluster goes
out. DSC is available once again without
restriction.
Deactivating DSC
Press the DSC button for at least 3 sec-
onds; the DSC indicator lamp in the instru-
ment cluster lights up permanently. DSC is
deactivated.
Deactivating DSC automatically deacti-
vates DTC as well. The systems for
enhancing stability and traction are deacti-
vated, and there is no active braking inter-
vention or torque control.
A message appears on the Control Display.
Please note any supplementary information
that appears there.
To maintain optimal stability, drive
with the system on whenever possi-
ble.<
Reactivating DSC
Press the DSC button again briefly; the
indicator lamp in the instrument cluster
goes out. DSC is now activated.
The laws of physics cannot be
repealed, even with DSC. An appro-
priate driving style always remains the
responsibility of the driver. Therefore, do
not reduce the additional safety margin
again by taking risks.
Do not make any modifications to the DSC
system. Never allow anyone other than
authorized professional technicians to
carry out service or repairs on the DSC sys-
tem.<
DBC Dynamic Brake Control
When you apply the brakes rapidly, this
system automatically produces the maxi-
mum braking force boost and thus helps to
achieve the shortest possible braking dis-

Technology for comfort, convenience and safety
80 tance during panic stops. This system
exploits all of the benefits provided by ABS.
Do not reduce the pressure on the brake
pedal for the duration of the brake applica-
tion. When the brake pedal is released,
DBC is deactivated.
In the event of a malfunction, the
warning lamp in the instrument
cluster lights up yellow.
Have the system checked and repaired at
your BMW center as soon as possible.
Please note any information that appears
on the Control Display.
Warning lamp for Canadian models.
Active roll stabilization*
The concept
Active roll stabilization minimizes body roll
and optimizes vehicle stability during cor-
nering and evasive maneuvers.
Dynamic stabilizers at the front and rear
axles form the basis for active roll stabiliza-
tion. Suspension compliance adapts to suit
driving conditions, varying from perfor-
mance-oriented during cornering to
smooth and comfort-oriented when the
vehicle is proceeding in a straight line.
The system assumes operational status
each time you start the engine.
Driving with active roll stabilization
During vehicle operation, the system con-
tinuously runs through closed-loop control
cycles lasting only fractions of a second.
In case of malfunction
The symbol in the instrument clus-
ter lights up and a message
appears on the Control Display.
Please note any supplementary information
that appears there.
You can find more information on the
Check Control starting on page 68. If the active roll stabilization system is
deactivated in response to malfunc-
tion, please remember to adapt your speed
accordingly, especially in curves.
The suspension will be noticeably softer
and the vehicle will display a greater ten-
dency to tilt during cornering and in cross-
winds.
If a message stating that you should stop
appears on the Control Display in addition
to the red symbol, stop immediately and
switch off the engine. In this case the oil
level in the reservoir may have dropped
below the minimum, possibly owing to a
leak in the hydraulic system.
Please note any supplementary information
that appears on the Control Display.<
Flat Tire Monitor
The concept
The Flat Tire Monitor keeps track of the
inflation pressures in the four fitted tires as
you drive. The system provides an alert
whenever the inflation pressure drops sig-
nificantly in relation to the pressure in
another tire.
The check of the tire inflation pressure is
based on monitoring the relative speeds of
the wheels. A flat tire is detected and
reported on the basis of a deviation in cer-
tain speed ratios.
Functional requirement
So that the Flat Tire Monitor can learn the
correct inflation pressure, please perform
the following:
1.Check the inflation pressures in all tires
2.Compare with the inflation pressure
table on page 170 and correct if neces-
sary
3.Initialize the system.
Limits of the system
The Flat Tire Monitor cannot indicate
sudden severe tire damage caused
by outside factors and does not detect a

Technology for comfort, convenience and safety
82
System malfunctions
Indicator lamp
The symbol in the instrument clus-
ter lights up yellow and a message
appears on the Control Display.
Please contact your BMW center.
Please note any supplementary information
that appears on the Control Display.
Active steering*
The concept
The active steering is a system that actively
varies the steering angle of the front wheels
in relation to the steering wheel move-
ments.
When you are driving in the low road speed
range, e.g. in a town or when parking, the
steering angle is reinforced, i.e. the steer-
ing becomes very direct and significantly
improves the handling capability of your
BMW.
In the higher road speed range, on the
other hand, the steering angle is reduced,
also optimizing the handling capability.
In critical situations, the system can make
targeted changes to the steering angle pro-
vided by the driver and thus stabilize the
vehicle before the driver intervenes.
Indicator lamp
The indicator lamp lights up perma-
nently: malfunction in the system.
Please have the system inspected
at your BMW center.
Conventional steering efficiency remains
available without limitations.
Brake Force Display
The Brake Force Display indicates the
intensity with which you are applying your
brakes to drivers of following vehicles. The display consists of two stages:
>Normal braking:
The brake lamps in the tail assemblies
and the high-mount brake lamp on top
of the rear window light up during brak-
ing
>Heavy braking and braking with ABS:
The tail lamps also light up with the
same intensity as the standard brake
lamp units to enhance the warning
effect of the brake lamps.

Things to remember when driving
106
Things to remember when driving
Break-in procedures
To ensure that your vehicle continues to
provide optimized economy of operation
throughout an extended service life, we
request that you devote careful attention to
the following section.
Engine and differential
Up to 1,200 miles/2,000 km:
You should attempt to vary both vehicle
and engine speeds. Until the break-in
period has been completed, you should
also refrain from exceeding an engine
speed of 4,500 rpm or a driving speed of
100 mph/160 km/h.
Always obey all official speed limits.
Avoid full-throttle operation and use of the
transmission's kickdown mode during
these initial miles.
Once you have driven 1,200 miles/
2,000 km, the engine and vehicle speeds
can be gradually increased.
You should also comply with these break-in
procedures should the engine or differen-
tial need to be replaced at a later point.
Sequential manual transmission
SMG
Do not use the acceleration assistant dur-
ing the break-in period.
Tires
Due to technical factors associated with
their manufacture, tires do not achieve their
full traction potential until after an initial
break-in period. Therefore, drive reservedly
during the first 200 miles/300 km.
Brake system
Brakes require an initial break-in period of
approx. 300 miles/500 km to achieve opti-
mized contact and wear patterns between
brake pads and rotors.
Clutch
The function of the clutch is only at its opti-
mized level after a distance driven of
approx. 300 miles/500 km. During this
break-in period, engage the clutch gently.
General driving notes
High temperatures
Extreme temperatures occur at the
catalytic converter on this and every
catalyst-equipped vehicle. Do not remove
the heat shields installed adjacent to vari-
ous sections of the exhaust system, and
never apply undercoating to them. When
driving, standing at idle and while parking
take care to avoid possible contact
between the hot exhaust system and any
highly flammable materials such as hay,
leaves, grass, etc. Such contact could lead
to a fire, and with it the risk of serious prop-
erty damage as well as personal injury.<
Parking the vehicle
Condensation forms in the air conditioner
system during operation, and then exits
under the vehicle. Traces of condensed
water under the vehicle are thus normal.
Before driving into the car wash
Fold in the exterior mirrors, refer to
page 42, as otherwise they could be dam-
aged due to the width of the vehicle.
Hydroplaning
When driving on wet or slushy roads,
reduce road speed. If you do not, a
wedge of water can form between tires and
road surface.This phenomenon is referred
to as hydroplaning, and is characterized by
a partial or complete loss of contact
between the tires and the road surface, ulti-
mately undermining your ability to steer
and brake the vehicle.<