2010 BMW 335I CONVERTIBLE page 38

Technology for driving comfort and safety
82 can drown out the PDC signal. Therefore,
always drive cautiously; otherwise, there is a
risk of personal injury or property damage.<
Driving stability control
systems
Your BMW has a number of systems that help
to maintain the vehicle's stability even in
adverse driving conditions.
Antilock Brake System ABS
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 page120.
Electronic brake-force distribution
EBV
The system controls the brake pressure in the
rear wheels to ensure stable braking behavior.
Dynamic Brake Control DBC
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 for the
duration of the full braking application.
Dynamic Stability Control DSC
DSC prevents the driving wheels from losing
traction when you pull away from rest or accel-
erate. The system also recognizes unstable
driving conditions, for example if the rear of the
car is about to swerve or if momentum is acting
at an angle past 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 at 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vidual wheels.The laws of physics cannot be repealed,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 reduce the additional
safety margin again by taking risks, as this could
result in an accident.<
Deactivating DSC
Press the button for at least 3 seconds; the indi-
cator lamps for DSC in the instrument cluster
light up. Dynamic Traction Control DTC and
DSC have been simultaneously deactivated.
Stabilizing and drive-output promoting actions
are no longer executed.
In the same way as with a differential interlock
*,
even if DSC is deactivated, brake actions are
still performed to enhance drive output if the
drive wheels experience a significant loss of
traction.
To increase vehicle stability, activate DSC again
as soon as possible.
Activating DSC
Press the button again; the indicator lamps in
the instrument cluster go out.
For better control
If the indicator lamp flashes:
DSC is regulating the drive and brak-
ing forces.
If the indicator lamps are on:
DSC is deactivated.
Dynamic Traction Control DTC
DTC is a version of DSC in which the drive out-
put is optimized for particular road conditions,

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>System has not been initialized
>Driving on snowy or slippery road surface
>Performance-oriented style of driving: slip
in the drive wheels, high lateral acceleration
>Snow chains are attached
Initializing the system
The initialization is completed during driv-
ing, which can be interrupted at any time.
When driving resumes, the initialization is con-
tinued automatically.
Do not initialize the system while snow chains
are attached.<
1."Vehicle Info"
2."Vehicle status"
3."Reset"
4.Start the engine – do not drive away.
5.Start the initialization using "Reset".
6.Start driving.
The initialization is completed during the trip.
"Status: Flat Tire Monitor active" is displayed
again on the Control Display.
Indication of a flat tire
The warning lamps come on in yellow
and red. A message appears on the
Control Display. In addition, an
acoustic signal sounds. There is a flat
tire or substantial loss of tire pressure.
1.Cautiously reduce speed to below 50 mph
or 80 km/h. Avoid sudden braking and
steering maneuvers. Do not exceed a speed
of 50 mph or 80 km/h.
If the car is not equipped with run-flat
tires, refer to page210, the standard equipment by design, do not continue driv-
ing. Otherwise, a severe accident could
result if you continue driving.<
2.At the next opportunity, check the air pres-
sure in all four tires.
If all four tires are inflated to the cor-
rect pressures, the Flat Tire Monitor
might not have been initialized. The system
must then be initialized.<
3.In the event of complete tire pressure loss,
0 psi/0 kPa, you can estimate the possible
distance for continued driving on the basis
of the following guidelines:
>With a light load:
1 to 2 persons without luggage:
Approx. 155 miles/250 km
>With a medium load:
2 persons, cargo area full, or 4 persons
without luggage:
Approx. 90 miles/150 km
>With a full load:
4 persons, cargo area full:
Approx. 30 miles/50 km
Drive cautiously and do not exceed a
speed of 50 mph or 80 km/h; otherwise,
there is a risk of an accident. In the event of
pressure loss, vehicle handling changes. This
includes reduced tracking stability in braking,
extended braking distance and altered natural
steering characteristics.
If unusual vibration or loud noises occur during
the journey, this may be an indication that the
damaged tire has finally failed. Reduce your
speed and pull over as soon as possible at a
suitable location. Otherwise, parts of the tire
could come loose, resulting in an accident. Do
not continue driving. Instead, contact your
BMW center.<
Status display
The current status of the Flat Tire Monitor can
be displayed on the Control Display, e.g.
whether or not the FTM is active.
1."Vehicle Info"
2."Vehicle status"

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3."Reset TPM"
4.Start the engine – do not drive away.
5.Start the initialization using "Reset TPM".
6.Start driving.
The tires are shown in gray and "Resetting
TPM..." is displayed.
After driving a few minutes, the set inflation
pressures in the tires are accepted as the target
values to be monitored. The system reset is
completed during your drive, and can be inter-
rupted at any time. When the trip is resumed,
the reset is continued automatically. On the
Control Display, the tires are shown in green
and "Status: TPM active" is displayed again.
If a flat tire is detected while the system is
resetting and determining the inflation
pressures, all tires on the Control Display are
displayed in yellow. The message "Low tire!" is
shown.<
Message for low tire inflation pressure
The warning lamps come on in yellow
and red. A message appears on the
Control Display. In addition, a signal
sounds. There is a flat tire or substan-
tial loss of tire pressure.
1.Cautiously reduce speed to below 50 mph/
80 km/h. Avoid sudden braking and steer-
ing maneuvers. Do not exceed a speed of
50 mph/80 km/h.
If the car is not equipped with run-flat
tires, refer to page210, the standard
equipment by design, do not continue driv-
ing. Otherwise, a severe accident could
result after a tire puncture if you continue
driving.<2.In the event of complete pressure loss,
0 psi/0 kPa, you can estimate the possible
distance for continued driving on the basis
of the following guidelines:
>With a light load:
1 to 2 persons without luggage:
Approx. 155 miles/250 km
>With a medium load:
2 persons, cargo area full, or 4 persons
without luggage:
Approx. 95 miles/150 km
>With a full load:
4 persons, cargo area full:
Approx. 30 miles/50 km
Drive cautiously and do not exceed a
speed of 50 mph/80 km/h. In the event of
pressure loss, vehicle handling changes. This
includes reduced tracking stability in braking,
extended braking distance and altered natural
steering characteristics.
If unusual vibration or loud noises occur during
the journey, this may be an indication that the
damaged tire has finally failed. Reduce your
speed and pull over as soon as possible at a
suitable location. Otherwise, parts of the tire
could come loose, resulting in an accident. Do
not continue driving. Instead, contact your
BMW center.<
Status display
The current status of the TPM Tire Pressure
Monitor can be displayed on the Control Dis-
play, e.g. whether or not the TPM is active.
1."Vehicle Info"
2."Vehicle status"
3."Tire Pressure Monitor - TPM"

Technology for driving comfort and safety
88 The status is displayed.
Malfunction
The small warning lamp flashes in
yellow and then lights up continu-
ously; the large warning lamp comes
on in yellow. On the Control Display,
the tires are shown in gray and a message
appears. No punctures can be detected.
This type of message is shown in the following
situations:
>If there is a malfunction
Have the system checked.
>If a wheel without TPM electronics has
been mounted
>If TPM is temporarily malfunctioning due to
other systems or devices using the same
radio frequency.
Message for unsuccessful system
reset
The warning lamp lights up yellow. A
message appears on the Control Dis-
play. The system is not reset, e.g.
after a wheel change.
Check the tire inflation pressure and reset the
system, refer to page86.
Declaration according to NHTSA/
FMVSS 138
Tire Pressure Monitoring Systems
Each tire should be checked monthly when cold
and inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle placard or tire inflation pressure label. If
your vehicle has tires of a different size than the
size indicated on the vehicle placard or tire infla-
tion pressure label, you should determine the
proper tire inflation pressure for those tires. As
an added safety feature, your vehicle has been
equipped with a tire pressure monitoring sys-
tem, TPMS, that illuminates a low tire pressure
telltale when one or more of your tires are signif-
icantly underinflated. Accordingly, when the
low tire pressure telltale illuminates, you should
stop and check your tires as soon as possible,
and inflate them to the proper pressure. Driving on a significantly underinflated tire causes the
tire to overheat and can lead to tire failure.
Underinflation also reduces fuel efficiency and
tire tread life, and may affect the vehicle’s han-
dling and stopping ability. Please note that the
TPMS is not a substitute for proper tire mainte-
nance, and it is the driver’s responsibility to
maintain correct tire pressure, even if underin-
flation has not reached the level at which the
TPMS low tire pressure telltale illuminates.
The TPMS malfunction indicator is combined
with the low tire pressure telltale. When the sys-
tem detects a malfunction, the telltale will flash
for approximately one minute and then remain
continuously lit. This sequence will continue
upon subsequent vehicle startups as long as
the malfunction exists. When the malfunction
indicator is illuminated, the system may not be
able to detect or signal low tire pressure as
intended. TPMS malfunctions may occur for a
variety of reasons, including the installation of
replacement or alternate tires or wheels on the
vehicle that prevent the TPMS from functioning
properly. Always check the TPMS malfunction
telltale after replacing one or more tires or
wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow
the TPMS to continue to function properly.
Active steering*
The concept
Active steering varies the turning angle of the
front wheels in relation to steering wheel move-
ments. It also varies the steering force required
to turn the wheels depending on the speed at
which you are driving.
When you are driving in the low road speed
range, e.g. in a town or when parking, the steer-
ing angle is increased, i.e. steering becomes
very direct and less effort is required to turn the
wheels. In the higher speed range, on the other
hand, the steering angle is reduced as the
speed increases. This improves the handling of
your BMW over the entire speed range.

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In critical situations, the system can make tar-
geted corrections to the steering angle pro-
vided by the driver and thus stabilize the vehicle
before the driver intervenes. This stabilizing
intervention is simultaneously deactivated
when DSC is switched off, refer to page82.
Malfunction
The warning lamps light up and a
message is displayed on the Control
Display. Active steering is malfunc-
tioning or is temporarily deactivated.
At low speeds, greater steering wheel move-
ments are required, whereas at higher speeds
the vehicle reacts more sensitively to steering
wheel movements. The stability-enhancing
feature may also be deactivated. Drive cau-
tiously and think well ahead.
Deactivation
Active steering is deactivated to perform an ini-
tialization. A message indicates that the feature
is deactivated. Initialization may take several
minutes.
If the message does not disappear during the
current trip, have the system checked.
Defect
If there is a defect, a corresponding text mes-
sage appears. Have the system checked.
Servotronic*
The concept
The Servotronic varies the steering force
required to turn the wheels relative to the vehi-
cle speed.
At low speeds, the steering force is strongly
assisted, i.e. less force is needed for steering.
As the vehicle speed increases, the steering
assisting power is reduced.
Malfunction
Malfunctions are displayed via Check Control,
refer to page77.
Brake Force Display
On the left: normal braking.
On the right: sharp braking.

Technology for driving comfort and safety
90
Airbags
The following airbags are located under the
marked covers:
1Front airbags
2Coupe: head airbags
3Side airbags in the seat backrests
4Convertible: knee airbags
Protective action
Observe the adjustment instructions on
page42 to ensure the best possible per-
sonal protection.<
The front airbags help protect the driver and
front passenger by responding to frontal
impacts in which safety belts alone cannot pro-
vide adequate restraint. When needed, the
head and side airbags help provide protection in
the event of side impact. The relevant side air-
bag supports the side upper body area. The
head air bag supports the head.
The airbags have been designed to not be trig-
gered in every collision situation, e.g. not in
minor accidents or rear-end collisions.
Do not apply adhesive materials to the
cover panels of the airbags, cover them or
modify them in any other way.
Keep the dashboard and windows on the front
passenger side clear, i.e. do not cover with
adhesive labels or coverings, and do not attach
holders such as for navigation instruments or
mobile phones.
Do not attach seat covers, cushions or other
objects not specifically approved for seats with
integral side airbags to the front seats. Do not
hang items of clothing such as coats or jackets over the backrests. Do not attempt to remove
the airbag retention system from the vehicle. Do
not modify the individual components of the
system or its wiring in any way. This includes
the upholstered covers on the steering wheel,
instrument panel, seats and roof posts, as well
as the sides of the roof lining. Do not attempt to
remove or dismantle the steering wheel.
Do not touch the individual components imme-
diately after the system has been triggered,
because there is a danger of burns.
In the event of malfunctions, deactivation or
triggering of the airbag restraint system, have
the testing, repair, removal and disposal of air-
bag generators executed only by a BMW center
or a workshop that works according to repair
procedures of BMW with correspondingly
trained personnel and that has the required
explosives licenses. Unprofessional attempts to
work on the system could lead to failure in an
emergency or to undesired airbag activation,
either of which could result in personal injury.<
Warning notices and information about the air-
bags can also be found on the sun visors.
Automatic deactivation of the front
passenger airbags
An analysis of the impression in the front pas-
senger seat cushion determines whether and
how the seat is occupied. The front and side air-
bags for the front passenger are activated or
deactivated by the system accordingly.
The indicator lamp above the interior
rearview mirror shows the current status
of the front passenger airbags, deactivated or

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activated, refer to Status of front passenger air-
bags below.<
Before transporting a child on the front
passenger seat, read the safety precau-
tions and handling instructions under Trans-
porting children safely, refer to page52.
The front and side airbags can also be deacti-
vated by adolescents and adults sitting in cer-
tain positions; the indicator lamp for the front
passenger airbags comes on. In such cases, the
passenger should change his or her sitting
position so that the front passenger airbags are
activated and the indicator lamp goes out. If the
desired airbag status cannot be achieved by
changing the sitting position, transport the rele-
vant passenger on a rear seat. Do not attach
seat covers, seat cushion padding, ball mats or
other items to the front passenger seat unless
they are specifically recommended by BMW.
Do not place any items under the seat which
could press against the seat from below. Other-
wise, a correct analysis of the seat cushion is
not ensured.<
Status of front passenger airbags
The indicator lamp for the front passenger air-
bags shows the functional status of the front
passenger front and side airbags in accordance
with whether and how the front passenger seat
is occupied. The indicator lamp shows whether
the front passenger airbags are activated or
deactivated.
>The indicator lamp lights up when a child in
a specially designated child restraint sys-
tem is detected, as intended, on the seat.
The front and side airbags for the front pas-
senger are not activated.Most child seats are detected by the
system, especially child seats
required by the NHTSA at the time of vehi-
cle production. After mounting a child seat,
ensure that the indicator lamp for the front
passenger airbag is lit. It indicates that the
child seat has been detected and that the
front passenger airbags are deactivated.<
>The indicator lamp does not come on as
long as a person of sufficient size and in a
correct sitting position is detected on the
seat.
The front and side airbags for the front pas-
senger are activated.
>The indicator lamp does not come on if the
seat is empty.
The front and side airbags for the front pas-
senger are not activated.
Operational readiness of airbag system
As of radio readiness, refer to page55, the
warning lamp comes on briefly to indicate that
the entire airbag system and the belt tensioners
are operational.
Airbag system malfunction
>Warning lamp does not light up at radio
readiness or beyond.
>Warning lamp remains permanently on.
In the event of a fault in the airbag system,
have it checked without delay; otherwise,
there is the risk that the system will not function
as intended even if a sufficiently severe acci-
dent occurs.<

Technology for driving comfort and safety
92
Convertible: rollover
protection system
The rollover protection system is activated
automatically in the event of an accident, a crit-
ical driving situation, an extreme tilt in the car's
longitudinal axis or upon loss of ground contact.
The protection bars behind the rear head
restraints deploy within fractions of a second.
As a supplementary system to the reinforced
windshield frame, the rollover protection sys-
tem ensures that the necessary headroom is
maintained for all vehicle occupants.
Always keep the area of movement of the
rollover protection system clear.
In minor accidents, you are protected by the
fastened safety belt and, depending on acci-
dent severity, by the safety belt tensioner and
multi-phase airbag retention system.<
Resetting
If the rollover protection system was not
impacted after being automatically activated, it
can be reset by lowering the protection bars to
their original positions. This does not require
tools.
1.Push the locking lever to one side and hold
it there.
2.Push the protection bar halfway down from
above.
3.Release the locking lever.4.Push the protection bar down until it snaps
into place.
5.Repeat the procedure for the other protec-
tion bar.
Have the rollover protection system checked
after an unexpected activation.
Never move the retractable hardtop when
the rollover protection system is in the
activated position.
Do not make any modifications to the individual
components of the rollover protection system
or its cabling.
Work on the rollover protection system should
only be performed by a BMW center.
Incorrectly performed work on the system may
lead to system failure or incorrect operation.
To check the system and ensure flawless long-
term operation, always observe the service
intervals, refer to page73.<