2005 BMW Z4 ROADSTER 3.0I brake

Technology for safety and driving convenience
50
Technology for safety and driving
convenience
Driving stability control
systems
Your BMW is equipped with a series of systems
that help maintain driving stability even in
adverse driving situations.
Antilock Brake System ABS
ABS keeps the wheels from locking during
braking. Steering stability is maintained even
during full brake applications. In this way, active
safety is enhanced.
ABS is operational each time the engine is
started. Braking safely, refer to page69.
Electronic brake-force distribution
The system controls brake-force application at
the rear wheels in order to obtain increased sta-
bility in the vehicle's braking response.
Dynamic Brake Control DBC
When the brake pedal is depressed quickly, this
system automatically supplies maximum brake-
servo boost, thereby helping to keep the vehi-
cle's braking distance as short as possible dur-
ing full brake applications. At the same time, the
benefits of the ABS are also exploited.
As long as you are braking, do not reduce pres-
sure on the brake pedal. When the brake pedal
is released, the DBC is switched off.
Dynamic Stability Control DSC
DSC prevents slip at the drive wheels while
starting off and accelerating the vehicle. DSC
also recognizes unstable vehicle conditions,
such as fishtailing or nose-diving. In these
cases, and subject to physical limits, DSC helps
to keep the vehicle on a steady course by
reducing engine speed and by applying brakes
at individual wheels.The laws of physics cannot be repealed
even with DSC. It will always be the
driver's responsibility to drive in a manner that
matches road conditions. Therefore, do not
limit the additional safety margin by practicing
risky driving.<
Dynamic Traction Control DTC
DTC is a variant of the DSC in which forward
momentum is optimized for special road condi-
tions, e.g. snow-covered roads that have not
yet been cleared. The system ensures maxi-
mum forward momentum, but driving stability is
limited. Therefore, drive carefully in accordance
with conditions.
In the following exceptional circumstances, it
may be effective to activate the DTC for a short
period:
>When driving on snow-covered grades, in
slush or on uncleared, snow-covered roads
>When rocking the vehicle or starting off in
deep snow or on loose surfaces
>When driving with snow chains.
Activating DTC
Press the button briefly; the DTC indicator lamp
lights up in the instrument cluster.
Reactivating DTC
Press the button again; the DTC indicator lamp
goes out in the instrument cluster.

Reference
At a glance
Controls
Driving tips
Mobility
51
Deactivating DTC and DSC at the same
time
Press and hold the button for at least
3 seconds; the DSC indicator lamp lights up in
the instrument cluster. No more interventions
to increase stability and forward momentum are
carried out.
To enhance vehicle stability, reactivate DSC as
soon as possible.
Reactivating DSC
Press the button briefly; the indicator lamp goes
out in the instrument cluster.
Checking
The indicator lamp flashes:
DSC or DTC is regulating drive torque
and braking forces.
The indicator lamp lights up:
DTC and DSC have been deactivated together
by pressing the DTC button.
The indicator lamp lights up:
DTC has been activated by pressing
the DTC button.
The DSC indicator lamp flashes and the
DTC indicator lamp is lit:
DTC is actively regulating drive torque
and braking forces.
Malfunction in the driving stability
control systems
The warning lamp for the brake system
lights up in red, together with the yellow
indicator lamps for ABS and DSC:
The driving stability control systems
have failed.
Continue driving cautiously and defensively.
Avoid hard brake applications. Have the system
checked immediately.
Indication of the above-described mal-
function in Canadian models.
The DSC warning lamp lights up
together with the yellow warning lamp
for the brake system:
DSC, including DTC and DBC, are mal-
functioning.
The stabilizing interventions are no longer avail-
able. The vehicle remains operational. Have the
system checked as soon as possible.
Indication of the above-described mal-
function in Canadian models.

Technology for safety and driving convenience
52
Brake force display
The Brake force display lights up in two stages
depending on how strongly you are braking.
>Normal braking:
The brake lamps and the center brake lamp
light up
>Hard braking or braking with ABS:
In addition, the illuminated surface of the
brake lamps is extended, refer to the pic-
ture.
Flat Tire Monitor
The concept
As you drive, the Flat Tire Monitor keeps track
of pressure levels in all four tires. The system
alerts you whenever the inflation pressure of a
tire falls significantly below the pressure of
another tire.
In the event of tire pressure loss, the rolling
radius of the tire changes, thereby affecting the
rotational speed of the wheels. This change is
detected, and a flat tire warning is issued to the
driver.
System requirements
To ensure a reliable flat tire warning, the system
must be initialized with the correct tire inflation
pressures.
Each time you correct the pressure in a
tire, or change a wheel or tire, the system
must be re-initialized.<
System limitations
The Flat Tire Monitor cannot provide you
with advance warning of sudden and
severe tire damage caused by external factors
and does not detect the balanced and very
gradual pressure loss that takes place in all four
tires over an extended period of time.<
The system could issue a false warning or func-
tion in a delayed manner in the following situa-
tions:
>System was not initialized
>You are driving on a snow-covered or slip-
pery road surface
>Performance-oriented driving: slip at the
drive wheels, high levels of lateral accelera-
tion
>You are driving with snow chains.
Initializing the system
The initialization is completed while you
are driving, and can be interrupted at any
time. Initialization is automatically continued
when you continue driving.
When driving with snow chains, do not initialize
the system.<
1.Start the engine, but do not drive off
2.Press the button as long as you need to until
the yellow indicator lamp in the instrument
cluster lights up for a few seconds
3.Drive off.
Initialization is completed during the drive,
without any feedback issued.

Special operating instructions
68
Special operating instructions
Break-in procedures
Moving parts need to be given some time until
they can interact smoothly with one another. To
ensure that your vehicle provides maximum
economy throughout a long service life, we
request that you observe the following:
Engine and differential
Up to 1,200 miles/2,000 km:
Drive at varying engine and road speeds, but do
not exceed the following engine or road speed:
4,500 rpm / 4,500/min or 100 mph / 160 km/h.
Obey your local and state maximum speed lim-
its.
Refrain from using full throttle and avoid press-
ing the accelerator beyond the kickdown point.
After you have driven 1,200 miles/2,000 km,
you can gradually increase the engine or road
speeds.
Sequential manual gearbox SMG
Up to 1,200 miles/2,000 km:
Do not use the acceleration assistant during the
break-in period.
Tires
Due to technical factors associated with their
manufacture, tires do not achieve their full trac-
tion potential until an initial break-in period has
elapsed. You should therefore drive with extra
caution during the first 200 miles/300 km.
Obey your local and state maximum speed lim-
its.
When the vehicle is operated on wet or
slushy roads, a wedge of water may form
between the tire and the road surface. This phe-
nomenon is referred to as hydroplaning and can
lead to partial or complete loss of traction, vehi-
cle control and braking effectiveness. Reduce
your speed on wet roads.<
Brake system
Approx. 300 miles/500 km must elapse before
the brake pads and rotors achieve their optimal
surface and wear pattern.
To break in the separate parking brake drums,
apply the parking brake lightly when coasting to
a standstill – at a traffic signal, for instance; use
caution to avoid posing a danger to other road
users.
To avoid corrosion, repeat this procedure from
time to time.
The brake lamps do not come on when the
parking brake is set.
Vacuum for the brake system servo unit
on your BMW is available only when the
engine is running. When you move the car with
the engine off, e.g. by towing, substantially
higher levels of pedal force will be required to
brake the vehicle.<
Clutch
The clutch will achieve its optimal functionality
after approx. 300 miles/500 km. Shift gears
carefully during the break-in period.
After replacing components
Follow the same break-in procedure again if any
of the components mentioned above have to be
replaced in the future.
Driving notes
Close the luggage compartment lid
Operate the vehicle only when the lug-
gage compartment lid is completely
closed, otherwise exhaust fumes could pene-
trate into the interior of the vehicle.<
Should it be absolutely necessary to operate
the vehicle with the luggage compartment lid
open and with the convertible top closed:

Reference
At a glance
Controls
Driving tips
Mobility
69
1.Close all windows
2.Increase the air supply from the air condi-
tioner or automatic climate control to a high
level. Refer to page58 or61.
Hot exhaust system
High temperatures occur with every vehi-
cle equipped with a catalytic converter.
Heat shields are installed adjacent to some sec-
tions of the exhaust system. Never remove
these shields; do not apply undercoating to
their surfaces. When driving, standing at idle
and parking the vehicle, take care to avoid con-
tact between the hot exhaust system and flam-
mable materials, e.g. hay, leaves, grass, etc.
Such contact could lead to a fire, resulting in
serious personal injury and property damage.<
Hydroplaning
When driving on wet or slushy roads,
reduce vehicle speed. If you do not, a
wedge of water may form between the tires and
the road surface. This phenomenon can lead to
partial or complete loss of traction, vehicle con-
trol and braking effectiveness.<
Driving through water
Do not drive through water on the road if it
is deeper than 1 ft/30 cm, and then only at
walking speed. Otherwise, the vehicle's engine,
the electrical systems and the transmission
may be damaged.<
Use the parking brake on inclines
On inclines, keep the vehicle from rolling
by using the parking brake rather than by
slipping the clutch, which would lead to a high
degree of clutch wear.<
Braking safely
Your BMW is equipped with ABS as a standard
feature. If you are in a situation which requires
full braking, it is best to brake using maximum
brake pressure: panic stop. Since the vehicle
maintains steering responsiveness, you can still
avoid possible obstacles with a minimum of
steering effort.Pulsation at the brake pedal combines with
sounds from the hydraulic circuits to indicate to
the driver that ABS is in its active mode.
Wet roads
If the roads are wet or if there is heavy rain, it is
advisable to gently press the brakes for a brief
moment every few miles/kilometers. Watch
traffic conditions to ensure that this maneuver
does not endanger other road users. The
resulting heat dries the brake rotors and brake
pads. Immediate braking force is then available
if necessary.
Inclines
To prevent overheating and, as a result,
diminished braking effectiveness, drive
down long or steep downhill grades in a gear
which requires the least braking. Otherwise,
even light but consistent pedal pressure can
lead to high temperatures, brake wear and pos-
sibly even brake failure.<
The braking power of the engine can be further
enhanced by downshifting the automatic trans-
mission in manual mode, if necessary, into first
gear; refer to pages39 and41. This prevents an
excessive load on the brakes.
Do not coast with the clutch depressed or
with the transmission or selector lever in
Neutral. Do not coast with the engine switched
off. Otherwise, the engine provides no braking
effect while the transmission is in idling posi-
tion, and there is no power-assist for braking or
steering when the engine is off.
Floor mats, floor carpets or other objects must
not be in the area near the brake or accelerator
pedal, as this could impair the movement of the
pedals.<
Corrosion on the brake rotors
Limited vehicle use, extended periods with the
vehicle parked or in storage, and operating con-
ditions in which braking is restricted to gentle,
low-pressure applications will all increase the
tendency for corrosion to form on the rotors and
contamination to accumulate on the brake
pads. This occurs because the minimal pres-

Special operating instructions
70 sure which must be exerted by the pads to
clean the rotors by brake applications is not
reached.
If the brake rotors are corroded, they will tend to
respond to braking with a pulsating effect which
even extended application will fail to cure.
Interior and exterior mirrors with
automatic dimming feature*
Two photocells in the interior rearview mirror
serve to control the interior and exterior mirrors

with automatic dimming feature. One photocell
is positioned in the mirror's lens, see arrow,
while the other is on the opposite side of the
mirror.
To ensure perfect functioning, keep the photo-
cells clean and the area between the interior
rearview mirror and the windshield free of any
obstruction like stickers, etc.
When the vehicle is parked
Condensation formed in the air conditioning
system during operation exits under the vehi-
cle. Traces of condensed water on the ground
underneath the vehicle are thus normal.
Mobile equipment in the vehicle
BMW advises against using mobile
equipment, e.g. cellular phones, inside
the vehicle without connecting them directly to
an outside antenna. Otherwise, it cannot be
ruled out that vehicle electronics and the mobile
equipment interfere with one another. In addi-
tion, it is not ensured that the radio waves emit-
ted during transmission are directed outside of
the vehicle interior.<
Cargo loading
Avoid overloading the vehicle so that the
permissible carrying capacity of the tires
is not exceeded. Otherwise, overheating and
inner damage to the tires may result. The ulti-
mate result can assume the form of a sudden air
loss.<
Determining the maximum load
1.Locate the following statement on your
vehicle's placard
*:
The combined weight of occupants
and cargo should never exceed
XXX kg or YYY lbs; otherwise damage to the
vehicle and unstable driving conditions
could result.<
2.Determine the combined weight of the
driver and passenger that will be riding in
your vehicle
3.Subtract the combined weight of the driver
and passenger from XXX kilograms or YYY
pounds
4.The resulting figure equals the available
amount of cargo and luggage load capacity.
For example, if the YYY amount equals
551 lbs. and there will be two 150 lbs. pas-
sengers in your vehicle, the amount of avail-
able cargo and luggage load capacity is
251 lbs.
551 lbs. minus 300 lbs. = 251 lbs.
5.Determine the combined weight of luggage
and cargo being loaded on the vehicle. That
weight may not safely exceed the available
cargo and luggage load capacity calculated
in Step 4.

Reference
At a glance
Controls
Driving tips
Mobility
85
Engine compartment
1Reservoir for the headlamp and windshield
washer system86
2Engine oil filler neck87
3Auxiliary terminal for jump-starting974Reservoir for brake fluid88
5Chassis ground, negative terminal
6Engine oil dipstick86
7Coolant expansion tank87

In the engine compartment
88
Checking the coolant level
1.The engine must be at ambient tempera-
ture
2.Open the cap of the expansion tank by turn-
ing it slightly counterclockwise to allow
accumulated pressure to escape, then
open completely
3.The coolant level is correct when the upper
end of the red float is at least even with the
upper edge of the filler neck but no more
than 3/4 in/2 cm above it, that is up to the
second mark on the float. Refer also to the
schematic diagram next to the filler neck
4.Slowly add coolant, if necessary, until the
correct level is reached; do not overfill
5.Turn the cap clockwise until it is tightly
closed
6.Have the cause for the coolant loss
removed as soon as possible.
Brake system
Malfunction
Brake fluid
The warning lamp lights up although
the parking brake is not engaged:
Stop the vehicle immediately.
The brake fluid level in the reservoir is too low.
At the same time, you may notice that brake
pedal travel is longer. Have the system checked
as soon as possible.
If you continue driving, extended pedal
travel may be necessary and braking dis-
tances may be significantly longer. Be sure to
adapt your driving style accordingly. function in Canadian models.
Brake pads
The warning lamp lights up. The brake
pads have worn down to the minimum
safe limit. Have the brake pads
replaced as soon as possible.
For your own safety: use only brake pads
which BMW has approved for your spe-
cific vehicle model. BMW cannot evaluate non-
approved brake pads to determine if they are
suitable for use, and therefore cannot guaran-
tee the operating safety of the vehicle in the
event of their use.<