2010 BMW Z4 ROADSTER SDRIVE30I traction control

Technology for driving comfort and safety
78 Loud sound sources outside or inside the car
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 page114.
Electronic brake-force distribution
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vidual wheels.The laws of physics cannot be repealed,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
s a f e t y m a r g i n a g a i n b y t a k i n g r i s k s , a s t h i s c o u l d
result in an accident.<
Deactivating/activating the DSC OFF
program
The program can be deactivated via Dynamic
Driving Control, refer to DSC OFF.
For better control
The indicator lamp flashes: DSC con-
trols the drive forces and brake forces.
The indicator lamp lights up: DSC has
failed.
DTC Dynamic Traction Control
The concept
The DTC system and the TRACTION program
are a variant of the DSC in which forward
momentum is optimized.
The system ensures maximum forward
momentum on special road conditions, e.g.,
unplowed snowy roads, but driving stability is
limited.
It is therefore necessary to drive with appropri-
ate caution.
You may find it useful to briefly activate DTC
under the following special circumstances:
>When driving in slush or on uncleared,
snow-covered roads.
>When rocking the vehicle or driving off in
deep snow or on loose surfaces.
>When driving with snow chains.
Deactivating/activating DTC Dynamic
Traction Control
The system and program can be deactivated/
activated via Dynamic Driving Control.

Controls
79Reference
At a glance
Driving tips
Communications
Navigation
Entertainment
Mobility
Dynamic Driving Control
The concept
Dynamic Driving Control can be used to adjust
the driving dynamics of the vehicle.
Several programs are available for this purpose;
they can be activated using the two Dynamic
Driving Control buttons.
The following characteristics are adapted,
depending on which program was selected:
>Engine response.
>Shift times of the automatic transmission
*.
>Power steering support
*.
>Changes in the suspension characteristics
through damping control
*.
>Vehicle stabilization through DSC Dynamic
Stability Control.
Operating the programs
1You can activate or deactivate the following
programs using this button:
>DSC OFF
>TRACTION
2You can activate or deactivate the following
programs using this rocker switch:
>SPORT+
>SPORT
>NORMAL
DSC OFF
Driving stability is limited during acceleration
and when driving in bends.
To increase vehicle stability, activate DSC again
as soon as possible.
Activating DSC OFF
Press and hold the button, but not
longer than approx. 10 seconds, until
the indicator lamp for the DSC lights up in the
instrument cluster and DSC OFF is displayed in
the instrument cluster.
The DSC system is switched off.
Deactivating DSC OFF
Press the button.
DSC OFF and the DSC indicator lamp
go out.
For better control
When DSC is switched off, DSC OFF is dis-
played in the instrument cluster.
The indicator lamp lights up: DSC is
deactivated.
TRACTION
Maximum traction on loose road surfaces. DTC
Dynamic Traction Control is switched on. Driv-
ing stability is limited during acceleration and
when driving in bends.

Technology for driving comfort and safety
80
Activating TRACTION
Press the button.
TRACTION is displayed in the instru-
ment cluster.
The DSC indicator lamp in the instrument clus-
ter lights up.
Deactivating TRACTION
Press the button again.
TRACTION and the DSC indicator
lamp go out.
For better control
When DTC is switched on, TRACTION is dis-
played in the instrument cluster.
The indicator lamp lights up: DTC
Dynamic Traction Control is activated.
SPORT+
Sporty driving with a tight suspension and lim-
ited driving stabilization.
Dynamic Traction Control is switched on.
The driver handles several of the stabilization
tasks.
Activating SPORT+
Press the button repeatedly until
SPORT+ appears in the instrument
cluster and the DSC indicator lamp lights up.
For better control
SPORT+ is displayed in the instrument cluster.
The indicator lamp lights up: DTC
Dynamic Traction Control is activated.
SPORT
Consistently sporty tuning of the suspension
for greater driving agility with maximum driving
stabilization.
Activating SPORT
Press the button repeatedly until
SPORT+ appears in the instrument
cluster.
NORMAL
For a balanced tuning with maximum driving
stabilization.
Activating NORMAL
Press the button repeatedly until the
program display disappears in the
instrument cluster.
Displays in the instrument cluster
The selected program is displayed in the instru-
ment cluster.
Drive-off assistant
The drive-off assistant enables you to drive off
smoothly on uphill gradients. The parking brake
is not required.
1.Hold the car in place by depressing the
brake.
2.Release the brake and drive off without
delay.
The drive-off assistant holds the car in
place for approx. 2 seconds after the
brake is released. Drive off without delay after
releasing the brake. Because the drive-off

Mobility
197Reference
At a glance
Controls
Driving tips
Communications
Navigation
Entertainment
Tire identification marks
Knowledge of the labeling on the side of the tire
makes it easier to identify and choose the right
tires.
Tire size
Speed code letter
Q = up to 100 mph or 160 km/h
T = up to 118 mph or 190 km/h
H = up to 131 mph or 210 km/h
V = up to 150 mph or 240 km/h
W = up to 167 mph or 270 km/h
Y = up to 186 mph or 300 km/h
Tire Identification Number
Tires with DOT codes meet the guidelines of
the US Department of Transportation.
DOT code:
Tire age
The manufacturing date of tires is contained in
the tire coding: DOT … 3709 means that the
tire was manufactured in week 37 of 2009.
BMW recommends that you replace all tires
after 6 years at most, even if some tires may last
for 10 years.
Uniform Tire Quality Grading
Quality grades can be found where applicable
on the tire sidewall between tread shoulder and
maximum section width. For example:
Tread wear 200 Traction AA
Temperature A
DOT Quality Grades
Tread wear
Traction AA A B C
Temperature A B C
All passenger car tires must conform to
Federal Safety Requirements in addition
to these grades.<
Tread wear
The tread wear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified gov-
ernment test course. For example, a tire graded
150 would wear one and one-half (1γ) times as
well on the government course as a tire graded
100. The relative performance of tires depends
upon the actual conditions of their use, how-
ever, and may depart significantly from the
norm due to variations in driving habits, service
practices and differences in road characteris-
tics and climate.
Traction
The traction grades, from highest to lowest, are
AA, A, B, and C.
Those grades represent the tire’s ability to stop
on wet pavement as measured under controlled
conditions on specified government test sur-
faces of asphalt and concrete. A tire marked C
may have poor traction performance.
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration, cor-
nering, hydroplaning, or peak traction charac-
teristics.< For example:
Nominal width in mm
Aspect ratio in %
Radial belt construction
Rim diameter in inches
Load rating,
not on ZR tires
Speed code letter, in
front of the R on ZR tires
225/45 R1791 V
For example:
Manufacturer's code
for tire make
Tire size and
tire design
Tire ageDOT xxxx xxx 3709

Reference 249
At a glance
Controls
Driving tips
Communications
Navigation
Entertainment
Mobility
Top, refer to Retractable
hardtop38
Top 50 of music
collection160
Torque, refer to Engine
data226
Tow bar221
Tow fitting220
– screw thread220
Tow fittings for tow-starting
and towing away220
Towing220
– car with automatic
transmission220
– methods221
Towing and tow-starting220
Town/city, for navigation121
Tow rope222
Tow-starting220,222
TPM, refer to Tire Pressure
Monitor82
Track
– selecting on CD152
Traction control, refer to
Dynamic Stability Control
DSC78
TRACTION program,
Dynamic Driving Control79
Traffic bulletins
– categories135
Traffic bulletins, filtering135
Traffic bulletins for
navigation133
– during destination
guidance135
– in map view135
Traffic jam
– displaying traffic
bulletins133Transmission
– automatic transmission with
Steptronic53
– dual clutch transmission55
– Launch Control58
– manual transmission53
– neutral56
– overriding selector lever lock
for automatic transmission
with Steptronic55
– reverse gear56
– transmission lock, releasing
manually58
Transmission interlock
– refer to Changing selector
lever position54
– refer to P Park54
Transmission lock, releasing
manually58
Transmission positions56
Transporting children
safely48
Transport securing devices,
refer to Securing cargo116
Travel instructions, refer to
Voice instructions132
Tread depth, refer to Minimum
tire tread198
Trip, deleting129
Trip, storing128
Trip-distance counter, refer to
Trip odometer64
Triple turn signal activation60
Trip odometer64
Trips, changing129
Turning circle, refer to
Dimensions227
Turn signal indicators
– indicator/warning lamp12
– triple turn signal60
Turn signals59
Tying down loads, refer to
Cargo loading116
U
Uniform Tire Quality Grading/
UTQR197Units
– average consumption68
– temperature68
Universal garage door opener,
refer to Integrated universal
remote control100
Universal mobile phone
preparation package, refer
to separate Owner's Manual
Universal remote control100
Unlatching, refer to
Unlocking34
Unlocking
– from inside32
– from outside29
– luggage compartment lid35
– setting unlocking
characteristics29
– without remote control, refer
to Comfort Access34
Updating the navigation
data120
USB audio interface163
USB interface103
V
VCD153
Vehicle
– battery216
– breaking in112
– cargo loading115
– Identification Number, refer
to Engine compartment202
– measurements, refer to
Dimensions227
– parking52
– weight228
Vehicle jack215
Vehicle storage211
Ventilation98
– air conditioner95
– draft-free95,98
Ventilation, refer to Climate93
Vents, refer to Air vents93
Vents, refer to
Ventilation95,98
Video menu154
Video playback153