BMW Z4 ROADSTER 2.5I 2004 E85 Workshop Manual

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49
Between the blue and red zones
Normal operating range. The needle may
rise as far as the edge of the red sector dur-
ing normal operation.
Red
When you switch on the ignition, warning
lamp 1 comes on briefly to indicate an
operational check.
Comes on while driving:
The engine has overheated. Stop and
switch the engine off immediately and
allow it to cool down.
For checking the coolant level, refer to
page 84.
Service interval display
Remaining distance to next service
The displays shown in the illustration
appear for a few seconds when the ignition
key is in position 1 or after the engine is
started.
The next service due appears with the
message OIL SERVICE or INSPECTION,
together with the distance remaining in
miles – in kilometers in Canada – before the
next scheduled service.
The computer bases its calculations of the
remaining distance on the preceding driv-
ing style.
A flashing message and a minus sign in
front of the number mean that the service
interval has already been exceeded by the
distance shown on the display. Please con-
tact your BMW center for an appointment.
Outside temperature
If the vehicle is not equipped with a com-
puter, the display in the instrument cluster
always shows the outside temperature.
Clock
If you wish to have a permanent time dis-
play, you can have it appear in the car radio
display, refer to the Owner's Manual for
Radio.
You can set the clock and the time display
in the car radio as follows.
To set
Ignition key in position 1 or higher:
Hours
1.Keep button 2 pressed for several sec-
onds until the hours are displayed and
the colon flashes
2.Press button 1 repeatedly until the
required hour is set
Minutes
3.Press button 2 to switch to the minutes
display

Everything under control
50 4.Press button 1 repeatedly until the
required minutes are set
5.Press button 2 to confirm the settings.
The set time of day is transferred to the car
radio display or appears in the instrument
cluster display.
Display mode
In ignition key position 0:
Press button 1.
The time of day is displayed for several
seconds.
Computer*
Mode selection
With the ignition key in position 1 or higher,
you can use the button in the turn signal
lever to retrieve information from the com-
puter for display in the instrument cluster.
Every time you press the button briefly in
the direction of the steering column, a new
function is called up for display.
The displays appear in the following order:
time of day, outside temperature, average
fuel consumption, cruising range, average
vehicle speed.
With the ignition key in position 1 or higher,
the last active setting is displayed.
If you wish, you can have all the dis-
plays of the following functions
shown in another unit of measure.<
Outside temperature
To change the units of measure,
°F/°C
While the temperature display is active,
keep the button in the turn signal lever
pressed until the display changes.
Ice warning
If the outside temperature drops to approx.
37.57/36, the computer automatically
switches to the outside temperature dis-
play.
In addition, a signal sounds and the display
flashes for a brief period.
Clock
Setting the 12-hour or 24-hour
mode*
If the vehicle is equipped with a computer,
you can have the time displayed in either a
12-hour or 24-hour mode.
While the time display is active, press the
computer button in the turn signal lever
until the display changes.

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Average fuel consumption
If you continue to press the button on the
turn signal lever, the average fuel con-
sumption last displayed is recalculated
from that point in time.
Any time spent when the vehicle is station-
ary and the engine shut off is ignored in the
calculation.
Cruising range
The computer bases its calculations of the
cruising range on the preceding driving
style and on the remaining fuel in the tank.
It is important that you refuel when
the cruising range falls below approx.
30 miles/50 km. Otherwise, the engine
cannot be guaranteed to operate properly
and damage may result.<
Average speed
If you continue to press the button on the
turn signal lever, the average fuel con-
sumption last displayed is recalculated
from that point in time.

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.

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If the brake warning lamp comes on
together with the yellow indicator
lamps for the Antilock Brake Sys-
tem ABS and 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 and warning lamps for
Antilock Brake System ABS and
Dynamic Stability Control DSC for
Canadian models.
Switching off DSC/Activating DTC
Press the DSC button briefly. The DTC indi-
cator lamp comes on and stays on.
DSC has been switched off; DTC is in ready
mode.
In the following exceptional circumstances,
it may be effective to activate the DTC for a
short period:
>When rocking the vehicle or starting off
in deep snow or on loose surfaces
>When driving on snow-covered grades,
in deep snow, or on a snow-covered
surface that has been packed down
from being driven on
>When driving with snow chains.
The gain in traction is achieved by a reduc-
tion in stabilizing intervention.
Switching off DSC and DTC
Hold the DSC switch down for at least
3 seconds. The DSC indicator lamp stays
lit.
In this case, no interventions to increase
stability and traction for the engine and
brakes are carried out.
To maintain vehicle stability, drive
with the DSC switched on whenever
possible.<
Reactivating DSC and DTC
Press the button again.
The indicator lamp goes out.
The laws of physics cannot be
repealed with DSC. It will always be
the driver's responsibility to drive in a man-
ner 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. Stabilizing interven-
tion is only performed to a limited degree
when the DTC is activated.
Do not make any modifications to the DSC
system. Allow only authorized technicians
to perform service procedures on the
DSC.<
Dynamic Brake Control DBC
If you step on the brake rapidly, this system
automatically produces maximum braking
force boost and thus helps to achieve the
shortest possible braking distance during
panic stops. All of the benefits of the ABS
system are exploited under these circum-
stances.
Do not reduce the pressure on the brake
pedal for the duration of the brake applica-
tion. When the brake pedal is released, the
DBC is deactivated.
Brake force display
The Brake force display indicates to the
road user behind you how hard you are
braking.

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

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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

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them to be deactivated, the airbags have to
be deactivated with the vehicle ignition key
and the key switch on the outer passen-
ger's side of the instrument panel. Apart
from passengers, do not place any addi-
tional objects on the passenger seat. Do
not fit seat covers, seat cushion padding,
ball mats or other items to the passenger
seat unless they are specifically recom-
mended by BMW. Do not place any items
under the seat. Otherwise, the function of
the seat occupation detection could be
impaired.<
Indicator lamps
Airbag system operational
The airbag indicator lamp in the instrument
cluster indicates the operational readiness
of the entire airbag system and the safety
belt tensioners as of ignition key position 1.
The indicator lamp goes out after a few
seconds.
The indicator lamp in the central console
signals whether or not the passenger air-
bag system is activated or deactivated as
of ignition key position 1.
This lamp pertains only to the passen-
ger airbag system.<>The indicator lamp goes out after a few
seconds:
The passenger airbags are active, e. g.
when an adult is traveling in the vehicle
or the seat is unoccupied
>The indicator lamp lights up continu-
ously:
The passenger airbags are deactivated,
e. g. when a child is traveling in the vehi-
cle in the child-restraint system.
For more information on the operating prin-
ciple of the passenger airbag system and
seat occupation detection, refer to Auto-
matic deactivation of the passenger air-
bags.
Airbag system malfunction
A system malfunction could prevent
the system from responding in the
expected manner to an impact occurring
within its normal response range.
Please have the airbag system inspected
immediately at a BMW center.<
There is a fault in the airbag system
if the airbag indicator lamp behaves
as follows:
>The indicator lamp does not light up as
of ignition key position 1
>The indicator lamp remains on continu-
ously
>The indicator lamp lights up while the
vehicle is being driven.

Controlling the climate for pleasant driving
58
Controlling the climate for pleasant
driving
Air conditioning
1Air onto the windshield and the side
windows
2Air for the upper body area59
3Air for the footwell
4Air distribution595Air conditioning59
6Outside-air/recirculated-air mode59
7Temperature adjustment59
8Air supply/blower59
9Rear window defroster59