2005 BMW 525I brake

Driving
60 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 differ-
ently from conventional cruise control systems
which you may be accustomed to, you are
strongly urged to read all of the pages relating
to this system before use. Pay special attention
to the information contained in the Things to
know about active cruise control section in this
manual beginning on page62.<
Vehicles with manual transmission
You can use the system in the 2nd to 6th gear
within a normal engine speed range and also
change gears. Continuous operation at very
high or very low engine speeds is not possible.
In this case the driver is asked to shift or the
system deactivates itself.
Vehicles with SMG
Continuous operation at very high engine
speeds is not possible in the Sequential mode.
In this case the driver is asked to shift or the
system deactivates itself.
In the Drive mode, the SMG acts similarly to the
automatic transmission in the D position.
Operating active cruise control
1Activate system, store and increase desired
speed
2Activate system, store and decrease
desired speed
3Deactivate system4Recall the stored speed and distance or
increase desired speed by 1 mph/1 km/h
with each press of the button
5Select distance to vehicle driving ahead.
You can choose from four available distance
settings. You will find more detailed infor-
mation on page62.
Adjust your desired speed to the traffic
conditions and remain ready to brake at
all times. Great differences in speed to the vehi-
cles driving ahead, e. g. when quickly approach-
ing a truck or when another vehicle swerves into
your lane, cannot be compensated for by the
system.<
Displays in instrument cluster
1Stored desired speed display
2Detected vehicle display. Lights up when
vehicle driving ahead is detected
3Selected distance to vehicle driving ahead
4Digital speed display.
Appears briefly when you select your
desired speed
The system is activated.
The display 3 appears as soon as
you activate the system and no
vehicle is detected driving ahead.
Vehicle detected.
The display 2 lights up yellow
when a vehicle is detected driving
ahead.

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The system requests that you
intervene by braking or with an
evasive maneuver. The display 2
flashes red and a signal sounds.
The active cruise control cannot
automatically restore the distance to the vehicle
driving ahead. You will find more detailed infor-
mation on page. You will find more detailed
information on page64.
Automatic intervention by ABS or
DSC, or you actuate the handbrake
while driving. The display 2 flashes
yellow. The active cruise control
now only intervenes by braking.
Desired speed, store and increase
Press the lever forward 1 at a driving speed of
more than approx. 20 mph/30 km/h:
The system applies and stores your current
speed as a desired speed. This speed is indi-
cated on the speedometer and displayed briefly
in the instrument cluster.
Subsequently pressing forward increases the
desired speed to the next multiple of 5 mph/
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 achieved, provided that
the road is clear.
If the display ACC --- mph/km/h briefly
appears in the instrument cluster, it might
be that conditions necessary for operation are
not currently being met.
To call up Check Control messages, refer to
page67.<
Desired speed, store and decrease
Pull back the lever 2:
The current driving speed is rounded off to the
next multiple of 5 mph/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 achieved, provided that the road is
clear.
Deactivate system
Press the lever up or down while the system is
active 3. The displays in the instrument cluster
disappear. You can use the system again as
required.
In addition, the system is deactivated automati-
cally:
>When you apply pressure to the brake pedal
>When you select the automatic transmis-
sion's/SMG's neutral position N
>When the manual transmission is shifted
into neutral
>When you deactivate the DSC Dynamic
Stability Control
>When you actuate the handbrake during
driving
>When the system reduces the speed to
below 20 mph/30 km/h due to a traffic situ-
ation
The system deactivates automatically
when the speed is set to below 20 mph/
30 km/h. An acoustic signal sounds and a mes-
sage 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.
Resume stored desired speed and
distance setting
Press button 4 when the system is deactivated.
The displays appear in the instrument cluster.
The system is reactivated and uses the last
stored desired speed and distance setting.

Driving
62
Fine adjustment of desired speed
In the activated state, the desired speed
increases by 1 mph/1 km/h each time button4
is pressed briefly.
Select distance
You can choose from four distance steps.
>Rotary switch downward:
Increase distance
>Rotary switch upward:
Decrease distance
The selected distance is displayed in the instru-
ment 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 appro-
priate following distance given road con-
ditions, traffic, applicable laws and driving rec-
ommendations for safe following distance.<
Things to know about active cruise control
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; heavy traffic such as during rush hour; 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 inter-
changes, 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 abil-
ity of the system does have physical limi-
tations. It will not apply the brakes or decelerate
your vehicle when there is a slow-moving vehi-
cle, stopped vehicle or stationary object ahead
of you, as for example, at a traffic light or a
parked vehicle. Also, the system does not react
to oncoming traffic, pedestrians or other types
of potential traffic such as a rider on horseback.
It is also possible that the system may not
detect smaller moving objects such as motor-
cycles or bicycles. Be especially alert when
encountering any of these situations as the sys-
tem will neither automatically 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 vehi-
cle 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,
unobstructed 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 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 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 sys-
tem 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 deacti-
vated whenever the driver applies the vehicle
brakes, shifts the transmission 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 braking. You
should then reactivate the system only when
you are fully aware of the prior speed and dis-
tance 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.
Behavior in curves
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 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 vehicle decelerates in either
case, you can choose to overcome the deceler-
ation by briefly pressing the accelerator pedal.

Driving
64
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 distance 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 accelera-
tor 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, particu-
larly 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 braking 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 braking,
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 instru-
ment cluster and sounding a signal.
Swerving vehicles
When a vehicle moves from an adjacent lane
into your lane, active cruise control will not rec-
ognize this vehicle until it is fully in your lane
ahead of your vehicle.
Malfunction
The indicator lamp lights up and a mes-
sage appears on the Control Display.
The build-up of foreign matter, e. g.,
snow, ice, dirt, road debris etc., can lead to
reduced detection performance of active cruise
control. You should check the sensor under the
front bumper and clean it as necessary prior to
driving your vehicle. If the sensor becomes cov-
ered by foreign matter 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 func-
tional, a message is displayed on the Control
Display and an acoustic signal is emitted.
When the system does not recognize any
objects, e.g. on infrequently traveled roads
without a shoulder or guard rails, the system
can automatically deactivate temporarily.

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Control Center, for principle details, refer to
page16.
1.Press button.
This opens the start menu.
2.Press the controller to open the menu.
3.Select "Vehicle settings" and press the
controller.
4.Select "PDC" and press the controller.
5.Select "Monitor display on" and press the
controller.
The PDC screen is activated.
The display appears on the Control Display as
soon as PDC is activated.
The setting for the remote control currently in
use is stored.
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 thin and wedge-shaped
objects, etc. Low objects already displayed, e. g. a curb, can also disappear from the detec-
tion area of the sensors again before a continu-
ous tone sounds. Loud noises from outside and
inside your vehicle may prevent you from hear-
ing the PDC signal tone.<
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
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. Safe braking, refer to page107.
CBC Cornering Brake Control
When braking during curves or when braking
during a gear change, driving stability and
steering response are improved further.
Electronic brake-force distribution
The system controls the brake pressure in the
rear wheels to ensure stable braking behavior.
DBC Dynamic Brake Control
When you apply the brakes rapidly, this system
automatically produces the maximum braking
force boost and thus helps to achieve the short-
est possible braking distance during full brak-
ing. This system exploits all of the benefits pro-
vided by ABS.
Do not reduce the pressure on the brake pedal
for the duration of the brake application. When
the brake pedal is released, DBC is deactivated.

Technology for comfort, convenience and safety
78
DSC Dynamic Stability Control
The system prevents traction loss in the driving
wheels when starting off and accelerating. DSC
also detects unstable driving conditions such
as a fishtailing rear end or sliding of the 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 individual wheels.
The DSC is operational every time you start the
engine.
The laws of physics cannot be repealed,
even with DSC. An appropriate driving
style always remains the responsibility of the
driver. Therefore, do not reduce the additional
safety margin again by taking risks.<
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.
Deactivating DTC again
Press the button again; the DTC indicator lamp
in the instrument cluster goes out.
Deactivating DTC and DSC together
Press the button until the DSC indicator lamp in
the instrument cluster lights up, but not longer
than approx. 10 seconds. Stabilizing and drive
output promoting actions are no longer exe-
cuted. In addition, the stability promoting inter-
vention of the active steering is deactivated,
refer to page81.
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.
Reactivating DSC
Press the button; the DTC indicator lamp in the
instrument cluster goes out.
To control
The indicator lamp flashes:
DSC or DTC controls the drive forces
and brake forces.
The indicator lamp lights up:
DSC and DTC are deactivated together via the
button DTC.
The indicator lamp lights up:
DTC is activated via the DTC button.

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Malfunction in vehicle stability-control
systems
The brake system warning lamp lights
up in red, appearing together with the
indicator lamps for ABS and DSC. A
message appears on the Control Dis-
play. The driving stability control sys-
tems are deactivated. Conventional
braking efficiency remains available
without limitations. While you may con-
tinue, you should remember to proceed cau-
tiously and drive defensively while avoiding full
brake applications. Have the system checked
as soon as possible.
Display of the previously described
malfunction on Canadian models.
The indicator lamp for DSC lights up; a
message appears on the Control Dis-
play. DSC and DTC are deactivated.
The stability maintenance functions are no
longer available. The vehicle remains in running
order. Have the system checked as soon as
possible.
The warning lamp for the brake system
lights up in yellow; a message appears
on the Control Display. DBC has failed.
Have the system checked as soon as possible.
Display of the previously described
malfunction on Canadian models.
Active roll stabilization*
The concept
Active roll stabilization minimizes body roll and
optimizes vehicle stability during cornering and
evasive maneuvers.
Dynamic stabilizers at the front and rear axles
form the basis for active roll stabilization. Sus-
pension compliance adapts to suit driving con-
ditions, varying from performance-oriented during cornering to smooth and comfort-ori-
ented when the vehicle is proceeding in a
straight line. During vehicle operation, the sys-
tem continuously runs through closed-loop
control cycles lasting only fractions of a second.
The system assumes operational status each
time you start the engine.
Malfunction
The warning lamp lights up and a mes-
sage appears on the Control Display.
There is a malfunction in the system.
Have the system checked as soon as possible.
If there is a malfunction in the system,
please remember to adapt your speed
accordingly, especially in curves. The suspen-
s i o n w il l b e n o t i c ea b ly s o f t e r a n d t h e v e h i cl e w il l
display a greater tendency to tilt during corner-
ing and in crosswinds. If a message stating that
you should stop appears on the Control Display,
stop and switch off the engine as soon as pos-
sible. In this case the oil level in the reservoir
may have dropped below the minimum, possi-
bly owing to a leak in the hydraulic system. Do
not continue driving. Contact your BMW cen-
ter.<
Flat Tire Monitor
The concept
The Flat Tire Monitor keeps track of the infla-
tion pressures in the four mounted tires as you
drive. The system provides an alert whenever
the inflation pressure drops significantly in rela-
tion to the pressure in another tire.
In the event of a pressure loss, the rolling radius
and therefore the rotation speed of the wheels
change. This change is detected and is
reported as a flat tire.
Functional requirement
In order to assure the reliable reporting of a flat
tire, the system must be initialized for the cor-
rect tire inflation pressure.
Perform the initialization immediately
after correcting the inflation pressure,