wheel BMW Z4 2.5I 2004 User Guide

Reference
At a glance
Controls
Driving tips
Mobility
39
Automatic transmission
with Steptronic*
You can drive as with a normal automatic
transmission. In addition, you can also shift
manually.
When you move the selector lever from the
D position to the left into the M/S range, the
performance-oriented shift programs of the
automatic transmission are engaged. As
soon as you briefly tap the selector lever in
the + or — direction, Steptronic changes the
gear. The manual mode is engaged. When
you wish to use the automatic transmission
mode again, move the selector lever to the
right to position D.
Selector lever positions
P R N D M/S + —
Range selection
A detent prevents inadvertent shifting into
selector lever positions R and P. To disen-
gage the detent, press the button on the
front of the selector lever knob, see arrow.
Shiftlock
While the vehicle is stationary and
before shifting out of P or N, depress
the footbrake in order to disengage the
selector lever's lock mechanism.<
Hold the footbrake down until starting
off. The vehicle will otherwise start to
move when a drive position is engaged.
If you leave the vehicle with the engine run-
ning, move the selector lever to the P posi-
tion and apply the parking brake. If you fail
to do this, the vehicle could move.
Do not leave the vehicle unattended with the engine running. An unattended vehicle
with a running engine poses a safety haz-
ard.<
PPark
Select reverse only when the vehicle is sta-
tionary. The transmission locks to prevent
the rear wheels from turning.
RReverse
Select reverse only when the vehicle is sta-
tionary.
NNeutral
Select only when stopping for an extended
period.
DDrive: automatic shift program
This position is designed for driving under
all normal operating conditions. All forward
gears are available.
Kickdown
In the kickdown mode, you achieve maxi-
mum acceleration in position D.
Depress the accelerator pedal past the
increased resistance point at the full-throt-
tle position.
M/S Manual mode and
Sport program
When you change from D to M/S, the Sport
program is activated. This is indicated in
the gear indicator by SD. The M/S mode is
recommended for performance-oriented
driving.
With the first brief touch, the automatic
transmission shifts from the Sport program
to the manual mode.
When you tap the selector lever in the +

Driving
40 direction, the transmission shifts up. When
the lever is tapped in the – direction, the
transmission shifts down. M1 to M 5 appear
in the gear indicator.
The Adaptive Transmission Control ATC
executes upshifts or downshifts only when
the new gear will provide a suitable combi-
nation of engine and road speed, e.g. ATC
will not execute downshifts if the engine
speed is too high. The desired gear will
appear briefly in the instrument cluster, fol-
lowed by the actual gear.
If you are driving in the manual mode
and wish to accelerate rapidly, e.g. to
pass another vehicle, shift down manually
or with the kickdown function.<
Shifting from M/S to selector lever posi-
tions P, R and N is possible only by going
through position D.
Available indicators
P R N D SD M1 M2 M3 M4 M5
Malfunction
If the indicator lamp comes on,
there is a malfunction in the trans-
mission system.
All of the selector lever positions can con-
tinue to be engaged; in the forward drive
positions, however, the vehicle will be
operating in the fourth gear only.
If this happens, avoid extreme engine loads
and consult the nearest BMW center.
Never work in the engine compart-
ment when a drive gear – forward or
reverse – is engaged. If you do so, the vehi-
cle could move. information beginning on page 94.
Sequential manual gearbox
SMG*
The concept
The sequential manual gearbox SMG is an
automated manual gearbox with which
clutching and shifting is assumed by an
electro-hydraulic system.
The SMG is operated via two shift paddles
on the steering wheel and the selector lever
in the center console.
It offers the following functions:
>Sequential mode: manual mode
>Drive mode: automated mode
>Ability to choose between two different
driving programs: Standard, Sport,
refer to Dynamic Driving Control
>Operating safety through protection
against misshifting
>Automatic upshifts and downshifts in
the drive mode
>Automatic downshifts at minimum
engine rpm
>Kickdown function in the drive mode
>Acceleration assistant.
Selector lever positions
The current selector lever position is shown
by a light-emitting diode on the center con-
sole.
R: Reverse
N: Neutral

Reference
At a glance
Controls
Driving tips
Mobility
41
Forward position with one-touch functions:
Sequential mode
+:manual upshifting
—:manual downshifting
D: drive mode.
The SMG is ready for operation in ignition
key positions 2 and 3.
The gearbox is automatically taken
out of gear if the driver's door is
opened while the engine is running and the
driver does not actuate the pedals, the shift
paddles or the selector lever.
This is accompanied by an acoustic signal
and the flashing gear indicator.
The gear indicator in the instrument cluster
displays N.
A driving position can only be engaged
when the driver's door is closed.
When the vehicle is unlocked, a buzzing
sound in the area of the transmission indi-
cates that the system is ready to operate.<
Shiftlock
For your safety, it is only possible to
engage a driving position from selector
lever position N when the footbrake is
depressed.
Please keep in mind while driving
When driving off on inclines, drive
smoothly without pausing. Do not
keep the vehicle in place by depressing the
accelerator pedal; instead, apply the park-
ing brake. Otherwise, the SMG gearbox
could overheat.<
RReverse
Select reverse only when the vehicle is sta-
tionary.
NNeutral
Always engage before starting the engine,
refer to Starting the engine.
Sequential mode
Each time the engine is started, the
sequential mode is activated as soon as you move the selector lever into the for-
ward driving position.
The gears are shifted via the shift paddles
or the selector lever.
It is also possible to drive off in second
gear, e.g. on snow-covered roads.
D Drive mode
In the drive mode all forward gears are
shifted automatically.
To switch from sequential to drive mode:
tap the selector lever to the right toward D.
For rapid acceleration, e.g. during passing,
depress the accelerator pedal completely:
kickdown.
Kickdown:
In the kickdown mode, you achieve maxi-
mum acceleration.
Depress the accelerator pedal past the
increased resistance point at the full-throt-
tle position.
To switch back to sequential mode: tap the
selector lever again to the right toward D,
or change the current gear via the shift
paddles or the selector lever.
Shifting gears
With selector lever
>To upshift, tap the selector lever
toward +
>To downshift, tap the lever toward —.
With shift paddles on steering wheel
>To upshift, pull one of the shift paddles
>To downshift, push the paddle.

Technology for safety and driving convenience
52
Technology for safety and driving
convenience
Dynamic Stability Control
DSC
The concept
This system optimizes driving stability and
traction, especially when just starting off,
when accelerating or when cornering. It
also maintains vehicle stability, even in crit-
ical driving situations.
DSC recognizes unstable vehicle condi-
tions, such as understeering or oversteer-
ing, and, within physically feasible limits,
helps keeping the vehicle on a steady
course by reducing engine speed and by
brake applications at individual wheels.
The DSC is operational every time you start
the engine. It includes the following func-
tions:
>Automatic Stability Control plus Trac-
tion ASC+T
>Dynamic Traction Control DTC
>Dynamic Brake Control DBC
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. We
therefore urge you to avoid using the addi-
tional safety margin of the system as an
excuse for taking risks.
Do not make any modifications to the DSC
system. Allow only authorized technicians
to perform service procedures on the
DSC.<
Indicator lamps
The indicator lamps in the instrument clus-
ter go out shortly after you switch on the
ignition.
Dynamic Stability Control DSC indi-
cator lamp flashes:
The system is active and governs
drive torque and braking forces.The indicator lamp stays lit:
Dynamic Stability Control DSC and
Dynamic Traction Control DTC have been
switched off via the button.
Dynamic Traction Control DTC indi-
cator lamp lights up permanently:
DTC has been deactivated via the
DSC button.
Dynamic Stability Control DSC indi-
cator lamp flashes:
Dynamic Traction Control DTC indi-
cator lamp lights up permanently:
DTC is actively regulating drive
torque and braking forces.
Interventions to increase stability are
being performed to a limited degree
only.<
The Dynamic Stability Control DSC
indicator lamp and yellow brake
warning lamp for Dynamic Brake
Control DBC light up continuously:
Dynamic Stability Control DSC,
Dynamic Traction Control DTC and
Dynamic Brake Control DBC are malfunc-
tioning.
Have the system repaired at your BMW
center.
Dynamic Stability Control DSC indi-
cator lamp and yellow brake warn-
ing lamp for Dynamic Brake Control
DBC for Canadian models:
The vehicle remains completely oper-
ational without the DSC, DTC and
DBC functions.<
In the event of a malfunction, please see
your BMW center.

Technology for safety and driving convenience
54 The display has two levels:
>Normal braking:
Brake lamp 1 lights up on both sides of
the vehicle together with the center
brake lamp
>Forceful braking and braking with ABS:
Brake lamps 1 and 2 light up on both
vehicle sides together with the center
brake lamp.
Antilock Brake System ABS
The concept
ABS keeps the wheels from locking during
braking, thereby enhancing active driving
safety.
Malfunctions
If the yellow indicator lamp for the
Antilock Brake System ABS comes
on together with the brake warning
lamp and the indicator lamp for the
Dynamic Stability Control DSC:
The entire ABS and DSC control
system has failed. Continue driving
cautiously and defensively. Avoid
hard brake applications. Please have the
system checked by your BMW center as
soon as possible.
Indicator lamp for the Antilock
Brake System ABS with the brake
warning lamp and the indicator
lamp for the Dynamic Stability Con-
trol DSC for Canadian models.
Braking with ABS
If you are in a situation which requires full
braking, you will exploit the full benefits of
the ABS system if you apply maximum
brake pressure: panic stop.
Pulsation at the brake pedal combines with
sounds from the hydraulic circuits to indi-
cate to the driver that ABS is in its active
mode.
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.
The system actually detects pressure loss
by monitoring differences in the relative
speeds of the four wheels. It interprets vari-
ations outside specified limits as severe
pressure loss, and then responds by gen-
erating a warning.
System requirements
In order for the Flat Tire Monitor to learn the
correct tire inflation pressure, please do the
following:
1.Check the tire inflation pressures in all
tires
2.Compare to the inflation pressure table,
refer to page 76, and correct if neces-
sary
3.Initialize the system.
If the system is not initialized,
undetected losses in pressure or
false warnings that indicate a non-exis-
tent flat tire are possible.<
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

Reference
At a glance
Controls
Driving tips
Mobility
55
place in all four tires over an extended
period of time.<
On the other hand, the following situations
can lead to false warning, a delayed detec-
tion of pressure loss and even to the sys-
tem not functioning:
>Driving on snow-covered or slippery
roads
>Performance-oriented driving: slip at
the drive wheels, high levels of lateral
acceleration
>When driving with snow chains, false
warnings and undetected pressure
losses may occur
>If the Flat Tire Monitor was not initial-
ized after the last time the tire inflation
pressures were corrected, undetected
losses in pressure or false warnings
that indicate a non-existent flat tire are
possible.
Initializing the system
Each time you correct the pressure in
a tire, or change a wheel or tire, reini-
tialize the system immediately afterwards.
This requires driving.<
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.
It takes a few minutes before the Flat Tire
Monitor can detect a flat tire and issue a
warning.
When driving with snow chains, do
not initialize the system.<
Flat tire warning
The indicator lamp in the instrument
cluster lights up in red. This visual
alert is accompanied by an acoustic
warning signal. There is a flat tire or a sign-
ficant loss of tire pressure.
1.Carefully reduce your speed to under
50 mph / 80 km/h. Avoid strong braking
and steering maneuvers. Do not exceed
a maximum speed of 50 mph / 80 km/h.
2.Check the inflation pressure in all four
tires as soon as possible.
Because the sides of Run Flat
tires are reinforced, a drop in infla-
tion pressure usually cannot be
detected from the outside, refer to Run
Flat tires on page 80.<
3.Before continuing to drive, refer to the
notes on page 80.
If the vehicle is not equipped with Run
Flat tires, refer to page 80, the stan-
dard equipment by design, continuing to
drive with a flat tire can result in serious
accidents.<
System malfunction
The indicator lamp in the instrument
cluster lights up yellow. The Flat
Tire Monitor is malfunctioning or out
of order. Please refer the problem to your
BMW center.

Technology for safety and driving convenience
56
Airbags
The following airbags are located under the
marked covers:
1Front airbags for driver and passenger
2Side airbags for driver and passenger
3Knee airbags for driver and passenger
Protective effect
The front airbags help protect the driver
and passenger in the event of a head-on
collision where the protection provided by
the safety belt alone would not be ade-
quate. The side airbags help provide pro-
tection in the event of a collision from the
side. Each of the side airbags is designed
to help support the seat occupant's upper
body. The knee airbags help provide addi-
tional protection in the event of a head-on
collision.
The airbags are deliberately not triggered
in every impact situation, e. g. less severe
accidents, certain roll-over conditions, or
rear-end collisions.
For information on the correct seating posi-
tion, refer to page 27.
Do not apply adhesive materials to
the cover panels of the airbags, cover
them or modify them in any other way. Do
not attempt to remove the airbag retention
system from the vehicle. Never modify or
tamper with either the wiring or the individ-
ual components in the airbag system. This
category includes the upholstery in the
center of the steering wheel, on the instru-
ment panel, the side trim panels on the
doors. Do not attempt to remove or dis-
mantle the steering wheel.
Do not touch the individual components directly after the system has been trig-
gered, because there is a danger of burns.
If you note any indication of system mal-
function, if you desire to have an airbag
deactivated, or if the airbag retention sys-
tem is triggered in response to an accident,
you should always entrust all inspection,
repair and dismantling operations to your
BMW center.
Unprofessional attempts to service the sys-
tem could lead to failure in an emergency
or undesired airbag activation, either of
which could result in personal injury.
To ensure compliance with official safety
regulations, please also entrust disposal of
airbag generators to a BMW center.<
Airbag warning information is also provided
on the sun visors.Automatic deactivation of the
passenger airbags
Before transporting a child on the
passenger seat be sure to observe
the information/instructions under Trans-
porting children safely, refer to page 33.<
Your BMW has a seat occupation detection
system. By evaluating the weight on the
passenger's seat, the system detects
whether or not the seat is occupied by a
child in the child-restraint system or an
adult.
>When a child is seated in the child-
restraint system, the front, side and
knee airbags are automatically deacti-
vated on the passenger's side.
>When an adult is traveling in the front
seat or it is unoccupied, the front, side
and knee airbags remain active on the
passenger's side.
Although not desired, it can occur in
the case of heavier children that the
passenger airbags remain active or, in the
case of very light adults or young persons,
that the passenger airbags are deactivated.
The condition of the passenger airbag sys-
tem is shown by the indicator lamp in the
central console, refer to Indicator lamps
below. If the indicator lamp signals that the
passenger airbags are active and you wish

Mobility
To ensure that you stay mobile,
the following chapter provides you with
important information on fuels and fluids,
tires and wheels, maintenance procedures
and steps to take in the event of a break-
down.

Reference
At a glance
Controls
Driving tips
Mobility
75
Wheels and tires
Tire inflation pressure
Information for your safety
It is not merely the tire's service life, but
also driving comfort and driving safety that
largely depend on the condition of the tires
and the maintenance of the specified tire
pressure.
Check tire inflation pressures regu-
larly and correct them if necessary: at
least every two weeks and before every
extended journey. If this is not done, incor-
rect tire pressures can cause driving insta-
bility or tire damage, ultimately resulting in
accidents.
Do not drive with a deflated, i.e. flat, tire
unless your vehicle is equipped with Run
Flat tires. A flat tire greatly impairs steering
and braking response, and can lead to
complete loss of control over the vehicle.<
Checking tire pressures
Check the tire inflation pressures only
when the tires are cold. This means after a
maximum driving distance of 1.25 miles/
2 km or if the vehicle has been parked for at
least 2 hours. Warm tires have higher infla-
tion pressures.
Reinitialize the Flat Tire Monitor after cor-
recting the tire inflation pressure. Refer to
page 55.
Inflation pressures for original tires
The specified inflation pressures for tires at
ambient temperature are provided on the
placard on the B-pillar and are visible when
the driver's door is open.
Inflation pressures for other tire
sizes
The following tire inflation pressure tables
show the inflation pressures for the speci-
fied tire sizes at ambient temperature.
Reinitialize the Flat Tire Monitor after
correcting the tire inflation pressure.
Refer to page 55.<
Tire size
The inflation pressures in the table apply to
BMW-approved tire sizes and brands. Your
BMW center will be glad to supply this
information.

Wheels and tires
76
Z4 2.5i
Z4 3.0i
TiresPressure specifications in psi/kPa
Tires
All pressure specifications in the table are
indicated in psi/kilopascal with cold tires,
cold = ambient temperature
225/50 R 16 92 V
225/45 R 17 91 W30/210 33/230
225/40 R 18 88 W 30/210 –
245/40 R 17 91 W
255/35 R 18 90 W–33/230
All winter tires 30/210 33/230
You will find more information about permissible loads and weights on page 101.
TiresPressure specifications in psi/kPa
Tires
All pressure specifications in the table are
indicated in psi/kilopascal with cold tires,
cold = ambient temperature
225/45 R 17 91 W 33/230 36/250
225/40 R 18 88 W 33/230 –
245/40 R 17 91 W
255/35 R 18 90 W–36/250
All winter tires 33/230 36/250
You will find more information about permissible loads and weights on page 101.