brake BMW 528I 2009 User Guide

Driving
72 Active cruise control represents a technological
advance over the familiar cruise control and is a
welcome relief from the constant adjustment of
speed that can accompany driving in traffic on
freeways or other high-speed thoroughfares.
Especially on longer trips and in traffic conges-
tion, the system can reduce fatigue and tension,
while increasing your enjoyment of driving.
Please use it safely and responsibly.
In addition to holding a steady cruising speed, if
you encounter slower vehicles ahead, active
cruise control will, within limits, adjust your
vehicle's speed automatically so that you can
flow with the traffic without having to make con-
stant adjustments. If, for example, while cruis-
ing at the selected speed, you begin to
approach a slower vehicle ahead of you in the
same lane, the system will reduce your vehicle's
speed to the same as that of the vehicle ahead
to maintain your selected distance setting. You
can vary the following distance, which will vary
with speed. Based on your selected distance
setting, the system automatically decreases the
throttle setting and lightly applies the brakes if
necessary. In addition, if the vehicle ahead of
you slows to a complete stop, the system can
follow this action within the given scope and
can also accelerate from a complete stop if the
vehicle ahead of you drives off again shortly
thereafter. During braking, your vehicle brake
lamps will automatically illuminate to alert a fol-
lowing driver to take action. In addition, it may
be necessary for your vehicle to downshift the
automatic transmission to maintain the dis-
tance setting selected. As soon as the road in
front of you has no moving vehicles, the system
will accelerate to your desired speed. This set
speed is also maintained on downhill grades,
however the vehicle speed can drop below the
set speed when driving uphill if the engine out-
put is not sufficient.
Active cruise control cannot detect stop
signs, red lights, or any object that is
stopped or is blocking the road.
Active cruise control is not and must not be
used as a collision avoidance/warning system.
Since this active cruise control system is a new
technology and operates differently from con-ventional cruise control systems which you may
be accustomed to, it is necessary that you read
all of the pages relating to this system before
use. Carefully read and observe the information
on the system limitations beginning on page76
to obtain a good command of the system and its
range of applications.<
Brake pedal feel
When the system brakes and you also depress
the brake pedal, a somewhat different braking
feel results.
Professional* navigation system
If a navigation DVD is in the drive, refer to
page142, within limits the system adjusts the
accelerating and braking behavior of the vehicle
to the road you are driving on.
To ensure that the system is informed of
the current course of the road, always use
the latest navigation DVD if possible.<
When the vehicle position is unknown, e. g.
when you leave the map area, this influence of
the navigation system is not available.
Applications
Please try the system first during sparse traffic
and clear road conditions so that you can get
used to the system. After you have experience
and understand the system, only then use it
during normal traffic.
As with conventional cruise control systems,
active cruise control in no way reduces or sub-
stitutes for the driver's own personal experi-
ence, responsibility, alertness and awareness in
adjusting speed, braking or otherwise control-
ling the vehicle. The driver should decide when
to use the system on the basis of road, traffic,
visibility, and weather conditions. Active cruise
control is intended for use on highway-type
roadways where traffic is moving relatively
smoothly as well as in slow-moving traffic. Do
not use the system in city driving; in complex
driving situations; heavy traffic such as during
rush hour; on curvy, winding roads, slippery
roads or roads with sharp curves such as high-
way off-ramps; during inclement weather such

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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, espe-
cially when the system is actively following a
vehicle in front of you. Otherwise, driving condi-
tions can result which lead to a violation of the
law or elevated risk of an accident.
The minimum initial activation speed is 20 mph/
30 km/h, and the maximum speed is 110 mph/
180 km/h. However, you can also activate the
system while stopped, refer to While stopped,
page74.
One lever for all functions
1Storing and increasing desired speed
2Storing and reducing desired speed
3Interrupting, refer to page74,
or deactivating system, refer to page75
4Activating stored desired speed and dis-
tance, refer to page74, or driving off, refer
to While stopped, page74
5Selecting distance to vehicle driving ahead,
refer to page73
Storing current speed
Tap the lever, arrow1, or briefly pull it, arrow2.The system stores the current vehicle speed. It
is indicated on the speedometer and briefly in
the instrument cluster.
Increasing desired speed
Press or tap the lever to the resistance point or
beyond, arrow1, until the desired speed is dis-
played.
The speed then displayed is stored and
achieved on a clear road.
>Each time the lever is tapped to the resis-
tance point, the desired speed is increased
by approx. 1 mph/1 km/h.
>Each time the lever is tapped beyond the
resistance point, the desired speed
increases to the next fives position in the
mph speedometer display or the next tens
position in the km/h speedometer display.
Reducing desired speed
Pull the lever, arrow2, until the desired speed is
displayed.
These functions are operated in the same man-
ner as increasing your desired speed.
Selecting distance
>Briefly press rocker switch downward:
Increase distance.

Driving
74 >Briefly press rocker switch upward:
Reduce distance.
The selected distance is displayed in the instru-
ment cluster.
Use good judgment to select the appro-
priate following distance, given road con-
ditions, traffic, applicable laws and State driving
recommendations for safe following distance.
Otherwise, a violation of the law or risk of an
accident could result.<
Interrupting cruise control
Press the lever upward or downward, and with
the vehicle stopped also depress the brake
pedal. The marking in the speedometer
changes color and the distance indicator goes
out.
In addition, the system is automatically inter-
rupted:>when you apply the vehicle brakes
>when you shift the transmission
>when DTC is activated or DSC is deacti-
vated
>when DSC comes on
>when you apply the handbrake
>when you release the safety belt and open
the driver's door with the vehicle stopped
>when the system does not recognize any
objects for an extended period of time, e. g.
on infrequently traveled roads without a
shoulder or guard rails, or if the radar sensor
is covered with dirt, refer to page75
If the system is interrupted, then it is nec-
essary for the driver to actively intervene
by braking and steering. Otherwise, there is a
risk of an accident.<
Resuming stored desired speed and
distance
While driving
Press button4.
The displays appear in the instrument cluster.
While stopped
Before leaving the vehicle with the engine
running, engage position P of the auto-
matic transmission and apply the handbrake.
Otherwise the vehicle can roll.<
If a detected vehicle in front of you brakes to a
complete stop and your vehicle has also been
braked to a complete stop by the system:
>If the vehicle in front of you drives off while
the marking1 for the desired speed in the
speedometer is green, your vehicle will
accelerate without you having to do any-
thing.
>If the vehicle in front of you drives off while
the marking1 is orange, you briefly depress
the accelerator pedal or press button4.
Rolling bars in the distance indicator3
mean that the vehicle in front of you has
driven off. Distance 1, closest
Distance 2
Distance 3
Distance 4, farthest
This distance is set when you acti-
vate the system.

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If you are stopped behind a vehicle with the
brake pedal depressed and the system is inter-
rupted or deactivated:
1.Press button4 to activate a stored desired
speed or select a desired speed with the
lever, arrow1 or arrow2.
2.Release the brake pedal.
3.If the vehicle in front of you drives off, briefly
depress the accelerator pedal or press
button4.
Deactivating system
>Press the lever upward or downward twice
while driving.
>When stopped, do the same with the brake
pedal depressed.
>Switch off the ignition.
The displays turn off, and the stored desired
speed and distance are deleted.
Displays in instrument cluster
1Stored desired speed
>Green: the system is active.
>Orange: the system is interrupted.
2Lights up yellow: vehicle detected ahead
Display also used for warnings, please read
all information on warnings
3Selected distance to vehicle ahead
The indicator lights up as soon as the sys-
tem is activated
The bars roll: the vehicle in front of you has
driven off
4Brief display of stored desired speedIf the display --- mph/--- km/h appears
briefly, the conditions necessary for oper-
ation may currently not be met.<
Warning lamps
The indicator2 continuously
flashes yellow.
The prerequisites for operating the
system are no longer met, e.g. as a
result of ABS or DSC interven-
tions. The system brakes until you actively take
over.
The indicator2 flashes red; a sig-
nal sounds.
The system indicates that you
must brake and/or maneuver the
vehicle yourself. The system can-
not automatically restore the distance to the
vehicle driving ahead.
However, this display cannot relieve the driver
of the responsibility for adjusting the desired
speed and driving style to the traffic conditions.
Radar sensors
1Long-range sensor
2Location of the short-range sensors behind
the bumper
3Location of the short-range sensors behind
the bumper with the M sports package
*
Heavy rain and also dirt, snow or ice can limit
the detection of vehicles ahead. If needed,
clean the radar sensor under the front bumper
as well as the bumper area covering the short
range sensors. When doing so, be particularly
careful in removing layers of snow and ice.

Driving
76 Do not apply adhesive labels etc. in the area of
the short-range sensors.If the sensor is not aligned properly, e. g. due to
damage, the active cruise control cannot be
activated.
System limitations
As with conventional cruise control sys-
tems, active cruise control in no way
diminishes or substitutes for the driver's own
personal responsibility, alertness and aware-
ness in adjusting speed, braking or otherwise
controlling the vehicle. The driver should
decide when to use the system on the basis of
road, traffic, visibility, and weather conditions.
Active cruise control is intended for use on
highway-type roadways where traffic is moving
relatively smoothly. Do not use this system in
city driving; in complex driving situations; on
curvy, winding roads, slippery 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, ser-
vice/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 sys-
tem is actively following a vehicle in front of
you.<
Always remember that the range and abil-
ity of the system do have physical limita-
tions. For example, the system may not detect
vehicles driving ahead if they suddenly brake
heavily in stop-and-go traffic during accelera-
tion. The system will not apply the brakes or
slow your vehicle when a very slow-moving
vehicle, stopped vehicle or stationary object is
in the lane ahead of you, for example when
approaching a traffic light or parked vehicle or
when a vehicle is stalled in your lane. Also, the system does not react to oncoming traffic,
pedestrians or other types of potential traffic
s u c h a s a r i d e r o n a h o r s e b a c k . I t i s a l s o p o s s i b l e
that the system may not detect smaller moving
objects such as motorcycles or bicycles. Be
especially alert when encountering any of these
situations as the system will neither automati-
cally 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 alertness.<
The system cannot allow the vehicle to drive off
automatically in situations that make driving off
considerably more difficult, e.g. on steep uphill
grades, with a heavy trailer or before raised
areas in the road.
Near radio astronomy stations, the system
radar is deactivated at speeds under 20 mph/
30 km/h due to legal regulations.
Be certain to interrupt the system when
you pull into an exit lane for a highway
offramp.<
Also, vehicles traveling in a staggered manner
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 that is actually in
the lane next to yours. Always be ready to take
action or apply the brakes if necessary.
In addition, the system is interrupted
whenever the driver applies the vehicle
brakes, shifts the transmission from drive/D to

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neutral/N, or deactivates DSC. After any inter-
ruption, 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 inter-
vene 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 can-
celed.
Unexpected lane change
If a vehicle in front of you is behind a stopped
vehicle and unexpectedly changes lanes, you
must react yourself, as the system does not
react to stopped vehicles.
Swerving vehicles
When a vehicle swerves out of adjacent lanes
into your lane, the system does not detect the
vehicle until it is completely in your lane.
When a vehicle ahead suddenly swerves
into your lane, the system may not be able to restore the selected distance automatically.
This also applies to great differences in speed
between your vehicle and vehicles ahead, e. g.
when quickly approaching a truck. Once the
system has established that a vehicle is indeed
in front of you, it will indicate that you must
brake and/or maneuver the vehicle yourself.
Take action yourself, otherwise there is a risk of
an accident.<
Behavior in curves
If the selected desired speed for a curve is too
high, the system reduces the speed within a
curve. However, it cannot detect curves in
advance. Therefore, select a suitable speed at
the start of a curve.
Because of the limited range of the system, it is
possible that in curves or on the peaks and val-
leys of hilly roads, a vehicle ahead may be rec-
ognized late, or not at all. Therefore, 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 might 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 vehicle decelerates in either

Driving
78 case, you can choose to overcome the deceler-
ation by briefly pressing the accelerator pedal.
Driver interventions and your
responsibility
Anytime the driver presses down on the
accelerator pedal, any braking action by
the system is interrupted and the distance indi-
cator goes out until the pedal is fully released.
As soon as you fully release the accelerator, the
system will again control your cruising speed
and distance setting. While driving with the sys-
tem activated, resting your foot on the acceler-
ator pedal will cause the system not to brake
even when necessary. Be certain that floormats
or other objects on the vehicle floor do not inter-
fere 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 sys-
tem to apply the brakes is also limited, e. g.
when you reduce your desired speed sharply. It
uses only a portion of braking system capacity
and does not utilize the full capacity of the vehi-
cle braking system. Therefore, the system can-
not decrease your speed due to large differ-
ences in speed between your vehicle and the
vehicle ahead. Example: 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.<

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1.Press the button.
This opens the start menu.
2.Press the controller to open the menu.
3.Turn the controller until "Settings" is
selected and press the controller.
4.Turn the controller until "Vehicle / Tires" is
selected and press the controller.
5.Change to upper field if necessary. Turn the
controller until "PDC" is selected and press
the controller.
6.Select "PDC display on" and press the con-
troller.
The PDC screen is activated.
The display appears on the Control Display as
soon as PDC is activated.
System limits
Even with PDC, final responsibility for
estimating the distance between the
vehicle and any obstructions always remains
with the driver. Even when sensors are pro-
vided, there is a blind spot in which objects can
no longer be detected. The system is also sub-
ject to the physical limits that apply to all forms
of ultrasonic measurement, such as those
encountered with tow bars and trailer cou-
plings, or thin and wedge-shaped objects etc. Low objects already displayed, e. g. curbs, can
also disappear from the detection area of the
sensors again before or after a continuous tone
already sounds. Higher, protruding objects, e.g.
ledges, cannot be detected. For this reason,
drive with care; otherwise, there is a danger of
personal injury or property damage.
Loud sources of sound, inside and outside the
vehicle, could drown out the PDC signal tone.<
Driving stability control
systems
Your BMW is equipped with an extended array
of systems designed to enhance and maintain
vehicle stability under extreme conditions.
ABS Antilock Brake System
ABS prevents locking of the wheels during
braking. Safe steering response is maintained
even during full braking. Active safety is thus
increased.
The ABS is operational every time you start the
engine. Braking safely refer to page136.
CBC Cornering Brake Control
When braking during curves or when braking
during a lane change, driving stability and steer-
ing response are improved further.
Electronic brake-force distribution
The system controls the brake pressure in the
rear wheels to ensure stable braking behavior.
Brake assistant
When you apply the brakes rapidly, this system
produces maximum braking force boosting and
thus helps to achieve the shortest possible
braking distance during full braking maneuvers.
This system exploits all of the benefits provided
by ABS.
Do not reduce the pressure on the brake pedal
for the duration of the full braking.

Technology for comfort, convenience and safety
92
Adaptive brake assistant*
In conjunction with the active cruise control
with the stop-and-go function, the adaptive
brake assistant ensures that the brake
responds even more quickly during braking
with the brake assistant.
DSC Dynamic Stability Control
DSC prevents traction loss in the driving wheels
when starting off and accelerating. The system
also identifies unstable driving conditions, such
as a loss of traction at the rear of the vehicle or
sliding of the vehicle in its front wheels. In these
cases, DSC helps the vehicle maintain a safe
course within physical limits by reducing engine
output and through braking actions in the indi-
vidual wheels.
The laws of physics cannot be repealed,
even with DSC. An appropriate driving
style always remains the responsibility of the
driver. Therefore, do not restrict the additional
safety margin with a risky driving style, as other-
wise there is a risk of an accident.<
Deactivating DSC
Press the button until the DSC indicator lamp in
the instrument cluster lights up, but not longer
than approx. 10 seconds. DTC Dynamic Trac-
tion Control and DSC are deactivated together.
Stabilizing and drive output promoting actions
are no longer executed. In addition, the stability
promoting intervention of the active steering
*
is deactivated, refer to page99.
A message appears on the Control Display.
Please note any supplementary information
that appears there.To increase vehicle stability, activate DSC again
as soon as possible.
Activating DSC
Press the button; the indicator lamp in the
instrument cluster goes out.
For better control
The indicator lamp flashes:
DSC controls the drive forces and
brake forces.
The indicator lamp lights up:
DSC is deactivated.
DTC Dynamic Traction Control
DTC is a version of DSC in which the drive out-
put is optimized for particular road conditions,
e.g. unplowed snow-covered roads. The sys-
tem assures the maximal drive output, but with
reduced driving stability. It is therefore neces-
sary to drive with appropriate caution.
You may find it useful to briefly activate DTC
under the following special circumstances:
>When driving on snowy inclines, in slush, or
on unplowed, snow-covered road surfaces
>When rocking a stuck vehicle free or start-
ing off in deep snow or on loose ground
>When driving with snow chains
*
Activating DTC
Press the button briefly; the DTC indicator lamp
in the instrument cluster lights up.
For better control
The indicator lamp flashes:
DTC controls the drive forces and
brake forces.

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The indicator lamp lights up:
DTC is activated.
Deactivating DTC
Press the button again; the DTC indicator lamp
in the instrument cluster goes out.
xDrive*
xDrive is the 4-wheel drive system of your
BMW. The combined effects of xDrive and DSC
further optimize the traction and dynamic driv-
ing characteristics. The 4-wheel drive system
xDrive variably distributes the drive torque to
the front and rear axle depending on the driving
situation and prevailing road conditions.
HDC Hill Descent Control*
The concept
HDC is a system for driving downhill in steep
terrain. This system reduces vehicle speed on
steep downhill gradients, thus allowing you to
maintain even better control of your BMW
under these conditions. The vehicle moves at
approximately twice walking speed without
active intervention from the driver.
HDC is available for activation at vehicle speeds
below approx. 22 mph/35 km/h. When driving
down steep hills with a speed below approx.
22 mph/35 km/h, the vehicle reduces speed
automatically down to approximately twice nor-
mal walking speed, approx. 7 mph/12 km/h, and
then keeps this speed constant.
You can use the accelerator or brakes to vary
this automatically controlled speed within a
range extending from approx. 3 mph/5 km/h to
15 mph/25 km/h.
You can specify a target speed within the same
range by using the lever of the cruise control
*.
Activating HDC
You can activate HDC:
>with the programmable buttons on the
steering wheel, refer to page56
>using iDriveiDrive, for operating principle refer to page16.
1.Press the button.
This opens the start menu.
2.Press the controller to open the menu.
3.Select "Settings" and press the controller.
4.Select "Vehicle / Tires" and press the con-
troller.
5.Change to upper field if necessary. Turn the
controller until "HDC" is selected and press
the controller.
6.Select "HDC on" and press the controller.
HDC is shown in the instrument cluster.
If the vehicle applies the brakes, a message is
displayed on the Control Display for approx.
20 seconds.
Deactivating HDC
When you use the programmable buttons on
the steering wheel or via iDrive, the HDC display
goes out.
HDC is automatically deactivated at speeds
greater than approximately 37 mph/60 km/h.
Using HDC
Manual transmission:
Use HDC in low gears and reverse gear.
Automatic transmission:
You can use HDC in every drive position.