2004 BMW 645CI COUPE&CONVERTIBLE ABS

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Indicator and warning
lamps
Technology that monitors itself
The indicator and warning lamps identified
by the
+ symbol are subjected to an oper-
ation check each time you switch on the
ignition or start the engine. They each light
up once for different periods of time.
When a malfunction occurs in a monitored
system, the corresponding lamp will either
fail to go out when the engine is started, or
it will come on again during normal driving,
usually accompanied by a Check Control
message. You will find more details on the
specified pages.
Fixed indicator and warning lampsColors The indicator and warning lamps can light
up in different colors and combinations.
>Red:
Stop immediately
or
important reminder
>Red and yellow:
Continue to drive; drive cautiously
>Yellow:
Have the system checked at the earliest
opportunity
or
for your information
>Green or blue:
For your information.
Variable indicator and warning lamps
On the display 5 of the instrument cluster,
other indicator and warning lamps appear
as necessary. Pay attention to the instruc-
tions of the accompanying Check Control
messages, also refer to page 66. Turn signals60
Active steering
+80
Brake system
+
With handbrake engaged55
With handbrake released78, 173
With other warning lamps78
Brake system for Canadian models
Airbags
+81
Service Engine Soon
+176
If the indicator lamp comes on
either continuously or intermit-
tently, this indicates a malfunction
the emissions-related electronic
systems.
Although the vehicle remains oper-
ational, you should have the sys-
tems checked by your BMW center
at the earliest possible opportunity
Service Engine Soon indicator
lamp for Canadian models
Front fog lamps86
ABS Antilock Brake System +78
DTC Dynamic Traction Control78
High beams/headlamp flasher86
Please fasten safety belt
+47
DSC Dynamic Stability
Control
+78
Check Gas Cap162
Lamp for US models

Opening and closing
32 If special circumstances should make it
absolutely necessary to operate the vehicle
with the lid open:
1.Coupe: close both windows as well as
the glass roof
Convertible: with closed top, close all
windows
2.Adjust the automatic climate control to
supply a high air volume, refer to
page 89.
Luggage compartment
There are four lashing eyes on the inner
corners of the luggage compartment for
securing luggage nets or securing straps to
fix luggage in position.
Also refer to Cargo loading, page 104.
Convertible: increasing luggage
compartment capacity
With the convertible top closed, you can
enlarge the luggage compartment capac-
ity:
To do so, unfold the handle and press it
downwards in the direction of travel, refer
to arrow. This folds the convertible top
compartment floor upwards.
Before opening the convertible top, run this
procedure in reverse order.
The convertible top cannot be
opened if the convertible top com-
partment floor is folded up.<
Alarm system
The concept
The vehicle alarm system responds:
>When a door, the hood, or the luggage
compartment lid is opened
>To movement in the vehicle interior:
interior motion sensor
>To changing of the vehicle's tilt if some-
one attempts to steal the wheels or tow
the vehicle
>To interruption of battery voltage.
The system responds to unauthorized vehi-
cle entry and attempted theft by simulta-
neously activating:
>An acoustic alarm, which lasts for a
period of approx. 30 seconds
>The hazard warning flashers for approx.
5 minutes
>The high beams, which flash on and off
in the same rhythm.
Arming and disarming alarm system
When you lock or unlock the vehicle, either
with the remote control or at the door lock,
the alarm system is armed or disarmed at
the same time.
The system indicates that it has been cor-
rectly armed by switching on the hazard
warning flashers for a single cycle and by
emitting an acoustic signal.
You can also open the luggage compart-
ment lid with the system armed using but-
ton on the remote control, refer to
page 28. When you close the lid, it is
secured again.
Switching off alarm
>Unlock the vehicle using the remote
control, refer to page 27
>or turn the ignition key to position 1.

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If the opening or closing action is inter-
rupted, it can happen that the luggage
compartment lid cannot be opened.<
Convenience operation using remote
control and driver's door lock
Refer to pages 27 and 29.
Manual closing in the event of an
electrical malfunction
Only close the convertible top manu-
ally if absolutely necessary; never
open it manually. The convertible top com-
partment lid cannot be locked in the event
of an electrical malfunction and would
open while the vehicle is being driven.
Improper handling can lead to damage.<
Before closing
1.Open the luggage compartment lid
2.Take the Allen wrench and screwdriver
from the onboard tool kit
3.Lever out the two buttons in the lug-
gage compartment with the screwdriver
and then pull firmly. The convertible top
compartment lid is unlocked
4.Close the luggage compartment lid
5.Move the side windows downwards
slightly; fully lower the rear window.
If the rear window cannot be opened
using the switch, it must be lowered
manually:Lever out the cover between the rear
head restraints. To do so, place the
screwdriver as close as possible to the
lock element, as shown in the illustra-
tion.
Carefully insert the Allen wrench in the
opening and turn firmly in the direction
indicated by the arrow until the rear
window is completely open.
Closing
Perform the following work steps with
the assistance of a second person
and with the doors open to prevent injury
and damage to the convertible top.<
1.Push the cover 1 on the left and right of
the side panel forwards. Reach into the
resulting openings and raise the con-
vertible top compartment lid 2 as far as
it will go

Technology for comfort, convenience and safety
76 indicate the presence of objects in green
before they are close enough to generate a
signal tone.
Control Center, for principle details, refer to
page 16:
1.Press button.
The start menu is opened
2.Press the controller to open the menu
3.Select "Vehicle settings" and press the
controller
4.Select "PDC" and press the controller
5.Select "Monitor display on" and press
the controller.
The PDC screen is activated.
The display appears on the Control Display
as soon as PDC is activated.
Depending on which key you have used to
open the vehicle, the last adjustment is
applied.
System limits
Even with PDC, final responsibility for
estimating the distance between the
vehicle and any obstructions always
remains with the driver. Even when sensors
are involved, there is a blind spot in which objects cannot be detected. The system is
also subject to the physical limits that apply
to all forms of ultrasonic measurement,
such as those encountered with thin and
wedge-shaped objects, etc. Low objects
already displayed, e.g. a curb, can also dis-
appear from the detection area of the sen-
sors again before a continuous tone
sounds.
Loud noises from outside and inside your
vehicle may prevent you from hearing the
PDC signal tone.<
Do not apply high pressure spray to
the sensors for a prolonged period of
time. Keep the spray at least 4 in/10 cm
away from the sensors.<
Driving stability control
systems
Your BMW is equipped with an extended
array of systems designed to enhance and
maintain vehicle stability under extreme
conditions. The following section describes
these functions based on ABS and DSC.
ABS Antilock Brake System
ABS enhances active safety by preventing
the wheels from locking under braking.
ABS is operational every time you start the
engine. ABS includes the functions CBC
Cornering Brake Control and EBV Elec-
tronic brake-force distribution.
CBC Cornering Brake Control
It provides further enhancements in vehicle
stability and steering response during lane
changes and cornering at high rates of lat-
eral acceleration.
EBV Electronic brake-force
distribution
EBV controls the brake system's applica-
tion pressure at the rear wheels to ensure
stable deceleration.

Technology for comfort, convenience and safety
78 The laws of physics cannot be
repealed, even with DSC. An appro-
priate driving style always remains the
responsibility of the driver. Therefore, do
not reduce the additional safety margin
again by taking risks.<
DBC Dynamic Brake Control
When you apply the brakes rapidly, this
system automatically produces the maxi-
mum braking force boost and thus helps to
achieve the shortest braking distance dur-
ing panic stops. This system exploits all of
the benefits provided by ABS.
Do not reduce the pressure on the brake
pedal for the duration of the brake applica-
tion. When the brake pedal is released,
DBC is deactivated.
Malfunctions of driving stability
control systems
The brake system warning lamp
lights up in red, appearing together
with the indicator lamps for ABS
and DSC. A message appears on
the Control Display. Driving stability
control and ABS have failed. Con-
ventional braking efficiency remains
available without limitations.
While you may continue, you should
remember to proceed cautiously and drive
defensively while avoiding full brake appli-
cations.
Have the system checked as soon as pos-
sible.
Display of the previously described
malfunction on Canadian models.
The DSC warning lamp lights up.
DSC and DTC have failed.
The stability maintenance functions
are no longer available. The vehicle will
remain completely operational, however,
without DSC.Have the system checked as soon as pos-
sible.
The warning lamp for the brake sys-
tem lights up yellow and a message
appears on the Control Display.
DBC has failed.
Have the system checked as soon as pos-
sible.
Display of the previously described
malfunction on Canadian models.
Active roll stabilization*
The concept
Active roll stabilization minimizes body roll
and optimizes vehicle stability during cor-
nering and evasive maneuvers.
Dynamic stabilizers at the front and rear
axles form the basis for active roll stabiliza-
tion. Suspension compliance adapts to suit
driving conditions, varying from perfor-
mance-oriented during cornering to
smooth and comfort-oriented when the
vehicle is proceeding in a straight line. Dur-
ing vehicle operation, the system continu-
ously runs through closed-loop control
cycles lasting only fractions of a second.
The system assumes operational status
each time you start the engine.
Malfunction
The warning lamp lights up and a
message appears on the Control
Display. There is a malfunction in
the system. Have the system checked as
soon as possible.
If there is a malfunction in the system,
please remember to adapt your
speed accordingly, especially in curves.
The suspension will be noticeably softer
and the vehicle will display a greater ten-
dency to tilt during cornering and in cross-
winds.
If a message stating that you should stop
appears on the Control Display, stop and
switch off the engine as soon as possible.
In this case the oil level in the reservoir may

Technology for comfort, convenience and safety
80
Report of a flat tire
The warning lamp lights up in red
and a message appears on the
Control Display. In addition, an
acoustic signal sounds. There is a flat tire
or extensive inflation pressure loss.
1.Cautiously reduce the vehicle speed to
below 50 mph/80 km/h. Avoid sudden
braking and steering maneuvers. Do
not exceed a vehicle speed of 50 mph/
80 km/h
Due to the reinforcement on the
side walls of the run-flat tires,
inflation pressure loss can not usually
be recognized from the outside, refer to
Run-flat tires on page 168.<
2.To continue driving, comply with the
instructions for driving with damaged
tires on page 168.
Malfunction
The warning lamp lights up yellow
and a message appears on the
Control Display. The Flat Tire Moni-
tor has a malfunction or has failed. Have
the system checked as soon as possible.
Active steering*
The concept
The active steering is a system that actively
varies the steering angle of the front wheels
in relation to the steering wheel move-
ments.
When you are driving in the low road speed
range, e.g. in a town or when parking, the
steering angle of the wheels is reinforced,
i.e. the steering becomes very direct.
In the higher speed range, on the other
hand, the steering angle of the wheels is
reduced more and more. This improves the
handling capability of your BMW over the
entire speed range.
In critical situations, the system can make
targeted changes to the steering angle pro-
vided by the driver and thus stabilize the
vehicle before the driver intervenes.
Malfunction
The fixed warning lamp lights up.
The active steering is no longer
operational. In the low speed range,
greater steering wheel movement is neces-
sary. Have the system checked.
If the warning lamp lights up during the first
engine starting following a power supply
interruption, the system must be activated
with initialization.
Initializing system
1.Start the engine
2.With the vehicle stationary, turn the
steering wheel from the straight-ahead
position to the left as far as it will go and
then back to the straight-ahead position
3.Switch off the engine.
When you start the engine again, all the
functions of the active steering are avail-
able once again.
Brake Force Display
The two-stage brake lamps light up in two
stages depending on how strongly you
brake.
>Normal braking:
The brake lamps and the third brake
lamp go on
>Heavy braking and braking with ABS:
In addition, the light area of the rear
brake lamps is enlarged, refer to illus-
tration.

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road surface. This phenomenon is referred
to as hydroplaning, and is characterized
by a partial or complete loss of contact
between the tires and the road surface, ulti-
mately undermining your ability to steer
and brake the vehicle.<
The risk of hydroplaning increases as the
tread depth of the tires decreases, also
refer to Tire tread on page 167.
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 at the most.
Otherwise, the vehicle's engine, the electri-
cal systems and the transmission may be
damaged.<
Braking safely
Your BMW is equipped with ABS as stan-
dard. The best way to achieve optimized
braking response from the ABS is to apply
maximum pressure to the brake pedal in
situations where this is required: panic
stops. Since the vehicle maintains steering
responsiveness, you can nevertheless
avoid possible obstacles with a minimum
of steering effort.
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.
Do not drive with your foot resting on
the brake pedal. Even light but con-
sistent pedal pressure can lead to high
temperatures, brake wear and possibly
even brake failure.<
Driving in wet conditions
While driving in wet conditions and in
heavy rain, it is a good idea to apply light
pressure to the brake pedal every few
miles. Monitor traffic conditions to ensure
that this maneuver does not endanger
other road users. The heat generated in this
process helps dry the pads and rotors to
ensure that full braking efficiency will then
be available when you need it.
Hills
To prevent overheating and thus
reduced efficiency of the brake sys-
tem, downshift to a gear in which only min-
imal brake applications are needed when
descending long or steep downhill
stretches. Even light but consistent pedal
pressure can lead to high temperatures,
brake wear and possibly even brake fail-
ure.<
You can further enhance the engine's brak-
ing effect by selecting a lower gear in the
automatic transmission's manual mode,
downshifting as far as first gear on
extremely steep stretches, refer to
page 59. This strategy helps you avoid
placing excessive loads on the brake sys-
tem.
Never drive with the clutch pressed
or allow the vehicle to coast with the
transmission in Neutral – or with the engine
switched off – there is no engine braking
when the transmission is in Neutral, and no
power assist for brakes and steering when
the engine is not running.
Never allow floor mats, carpets or any other
objects to protrude into the area around the
accelerator and brake pedals and obstruct
their movement.<
Corrosion on brake rotors
When the vehicle is driven only occasion-
ally, during extended periods when the
vehicle is not used at all, and in operating
conditions where brake applications are
less frequent, there is an increased ten-
dency for corrosion to form on rotors, while
contaminants accumulate on the brake
pads. This occurs because the minimum
pressure which must be exerted by the
pads during brake applications to clean the
rotors is not reached.
Should corrosion form on the brake rotors,
the brakes will tend to respond with a pul-
sating effect that even extended applica-
tion will fail to cure.

Wheels and tires
168
Run-flat tires
You will recognize run-flat tires by a circular
symbol containing the letters RSC on the
side of the tire.
Run-flat tires consist of self-contained tires
and special rims. The tire reinforcement
ensures that the tire retains some residual
safety in the event of pressure drop and
driving remains possible to a restricted
degree.
Continuing driving with a damaged
tire
Driving on run-flat tires with tire damage
can continue, depending on the vehicle
load and the severity of the tire damage, at
a maximum speed of 50 mph/80 km/h.
You can estimate the possible mileage for
continued driving on the basis of the fol-
lowing general indications:
>With low load:
1 to 2 persons without luggage:
Approx. 155 miles/250 km
>With medium load:
2 persons, luggage compartment full, or
4 persons without luggage:
Approx. 94 miles/150 km
>With full load:
4 persons, luggage compartment full:
Approx. 30 miles/50 km.
Drive reservedly and do not exceed
a speed of 50 mph/80 km/h. In the
event of pressure loss, vehicle handling
changes. This includes reduced track sta-
bility in braking, extended braking distance
and altered natural steering characteristics.
If unusual vibrations occur while the vehicle
is being driven, this can indicate final failure of the damaged tire. Reduce speed and
stop as soon as possible. Do not continue
driving. Contact your BMW center.<
New wheels and tires
You can find out the right wheel-tire combi-
nation from your BMW center. It is another
vital factor in ensuring reliable operation of
various vehicle systems such as ABS and
DSC. Have the wheel and tire assemblies
balanced every time either a wheel or a tire
is replaced.
Only have new wheels and tires
mounted by a specialist. If this work is
performed inexpertly, there is a danger of
damage and associated safety risks.<
Retreaded tires
BMW does not recommend the use of
retread tires, as otherwise driving
safety may be reduced. Possible variations
in the design and the age – which could be
substantial – of the carcasses can lead to
unusually rapid wear.<
The right wheels and tires
BMW recommends that you use only
wheel and tire combinations that
BMW has tested and approved for your
particular vehicle. Variations in factors such
as manufacturing tolerances mean that
even wheels and tires with identical official
size ratings could actually have different
dimensions than the approved units – these
differences could lead to body contact, and
with it the risk of severe accidents. If non-
approved wheels and tires are used, BMW
cannot evaluate their suitability, and there-
fore cannot be held liable for driving
safety.<
To maintain good handling and vehicle
response, use only tires of a single tread
configuration from a single manufacturer.
After a flat tire, always remember to have
the specified wheel and tire combination
remounted on the vehicle as soon as pos-
sible.