2003 BMW 540I SEDAN engine

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OverviewControlsMaintenanceRepairsDataIndex
Self-leveling suspension
*
Tire Pressure Monitor (RDC)
*
The warning lamp for the self-
leveling suspension comes on,
or the message "SELFLEVEL
SUSP.INACT" appears in the Check
Control: there is a malfunction in the
self-leveling suspension.
Stop and inspect the vehicle. If it is
riding significantly lower in the rear than
in the front, or if it is sitting at an incline
(left rear compared to right rear), con-
sult the nearest BMW center. Drive with
appropriate caution in the meantime.
The vehicle has reduced ground clear-
ance or driving comfort is noticeably
reduced.
Even if the attitude of the vehicle is
normal, you should consult the nearest
BMW center if the warning lamp indi-
cates a system fault.
The conceptRDC monitors the tire pressures at all
four wheels, even when the vehicle is
moving. The system provides an alert
whenever the inflation pressure drops
significantly below the specified pres-
sure in one or more tires.
In order for the system to "learn" the
correct tire inflation pressure, check the
inflation pressure in all tires. Refer to
the table of "Tire inflation pressures"
beginning on page 27 and make any
necessary corrections. Then activate
the system.
This indicator lamp in the instru-
ment cluster or the Check Con-
trol will inform you if the tire
pressure is not correct.
Activate the system1. Turn the ignition key to position 2 (do
not start the engine)
2. Maintain pressure on the button until
the yellow indicator lamp in the
instrument cluster comes on for sev-
eral seconds or the message "SET
TIRE PRESSURE" appears in the
Check Control panel
3. After you have driven for a few min-
utes, the RDC will import the current
inflation pressure in the tires as the
reference values which the system
will monitor.
You will only have to repeat this proce-
dure if the tire inflation pressure must
be corrected. Otherwise, the RDC func-
tions automatically when the ignition
key is in position 2, and thus operates
whenever the vehicle is driven.390de704

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OverviewControlsMaintenanceRepairsDataIndex
Air conditioningTemperature
The graduations on the dial
provide general reference
values for the interior temper-
ature. We recommend 70 7
(22 6) as a comfortable setting. When
you start the vehicle, this system
adjusts the air to the selected tempera-
ture as quickly as possible, and then
maintains that temperature constantly.
Air distribution
You can direct the emerging
air toward the windows ,
toward your upper body or
into the footwell . All inter-
mediate settings are also available. In
the setting, there is a low flow of air
onto the windows to keep them free of
condensation.
Air supply
You can control the emerging
air's flow rate through an infi-
nitely-variable range. The
heating and ventilation
become more and more effective as the
air supply settings are increased. In the
"0" setting, the blower and climate con-
trol are switched off and the outside air
supply is blocked.
Rear window defroster
The indicator lamp comes
on to indicate that the rear
window defroster is in operation. The
rear window defroster switches off
automatically.
Cooling
The air conditioning cools
and dehumidifies the
incoming air before reheating it to the
selected temperature. Depending on
the weather, the windshield may fog
over briefly when the engine is started.
You can reduce condensation forming
on the windows by switching on the air
conditioning.
Condensation forms in the air
conditioning system during opera-
tion, which then exits under the vehicle.
Traces of condensed water of this kind
are thus normal.<
Recirculated-air mode
You can respond to
unpleasant odors in the sur-
rounding environment by using this
mode to temporarily suspend the flow
of outside air into the vehicle's interior.
The system then recirculates the air
currently within the vehicle.
If your vehicle is equipped with a multi-
function steering wheel
featuring a
recirculated-air button then you can
also select the recirculated-air mode
from this location (refer to page 22).
If the windows should fog over in
the recirculated-air mode, switch
the recirculated-air mode off and
increase the air supply as required.<

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Automatic climate control
*
Air conditioning
The air is cooled and
dehumidified and Ð
depending on the temperature setting Ð
warmed again when the air conditioning
is switched on. Depending on the
weather, the windshield may fog over
briefly when the engine is started. You
can reduce condensation forming on
the windows by switching on the air
conditioning.
Condensation forms in the air
conditioning system during opera-
tion, which then exits under the vehicle.
Traces of condensed water of this kind
are thus normal.<
Maximum cooling
With the engine running
this program provides
maximum cooling at outside tempera-
tures above approx. 41 7 (5 6).
60 7 (16 6) appears in the tempera-
ture display 9, and the system reverts to
the recirculated-air mode while simulta-
neously providing maximum airflow
through the vent outlets only. That is
why you need to keep these open if you
select this program.
Automatic recirculated-air
control (AUC)
You can respond to
unpleasant external odors
by temporarily stopping the flow of out-
side air. The system then recirculates
the air currently within the vehicle.
Press the button repeatedly to run
through the following control sequence:
>Indicator lamps off: outside airflow
operational
>Left-hand indicator lamp on Ð AUC
mode: the system recognizes pollut-
ants in the outside air and blocks the
flow of air when necessary. The
system then recirculates the air cur-
rently within the vehicle.
Depending on the air quality, the
automatic system then switches back
and forth between outside air supply
and recirculation of the air within the
vehicle
>Right-hand indicator lamp on: the
flow of external air into the vehicle is
permanently blocked. The system
then recirculates the air currently
within the vehicle.
If you have a multifunction steering
wheel with the recirculated-air button
(refer to page 22), you can also use it to
switch between "Off" and the recircu-
lated-air mode or AUC and the recircu-
lated-air mode.
If the windows should fog over in
the recirculated-air mode, switch
the recirculated-air mode off and
increase the air supply as required.< Rear window defroster
When the rear window
defroster is activated, the
indicator lamp comes on. The rear
window defroster switches off automat-
ically.

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OverviewControlsMaintenanceRepairsDataIndex
Automatic climate control
*
Residual heating mode
The heat which is stored in
the engine is utilized for
heating the interior when the engine
has been switched off (while waiting at
a railroad crossing, for instance).
In ignition key position 1, you can alter
the settings of the automatic climate
control. In ignition key position 0, the
system automatically directs heated air
to the windshield, side windows and
footwells.
This function is available for oper-
ation when the outside tempera-
ture is below approx. 59 7 (15 6),
with the engine warm from recent oper-
ation and an adequate charge in the
battery. The LED on the button will light
up when all conditions have been
met.<
Draft-free ventilationYou can adjust the vent outlets for the
upper body area completely for your
personal comfort:
1 Rotary dials for infinitely-variable
opening and closing of the vent out-
lets
2 Selector levers for airflow direction
3 Rotary dial allows you to control the
temperature of the airflow as desired:
>Turn toward blue Ð colder
>Turn toward red Ð warmer.390de685
Rear passenger area ventilation1 Rotary dial for infinitely-variable
opening and closing of the vent out-
lets
2 Selector levers for airflow direction
3 The rotary dial operates in the same
way as the front dial to adjust the
temperature of the emerging air.390de686

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Break-in proceduresTo ensure that your vehicle provides
maximum economy throughout a long
service life, we request that you
observe the following suggestions.Engine and differentialUp to 1,200 miles (2,000 km):
Drive at varying engine speeds and
road speeds, but do not exceed
4,500 rpm and the following road
speeds during this initial period:
BMW 525i, 530i: 100 mph (160 km/h)
BMW 540i: 106 mph (170 km/h).
Comply with all official speed limits.
Refrain from using full throttle and avoid
pressing the accelerator beyond the
kickdown point.
Once you have driven 1,200 miles
(2,000 km), engine and vehicle speeds
can gradually be increased.
You should also comply with these
break-in procedures if the engine or dif-
ferential is replaced later in the course
of the vehicle service life.
TiresOwing to technical factors associated
with their manufacture, tires do not
achieve their full traction potential until
an initial break-in period has elapsed.
For this reason, you should drive with
extra care during the initial 200 miles
(300 km).
Comply with all official speed limits.
When the vehicle is operated on
wet or slushy roads, a wedge of
water may form between the tire and
the road surface. This phenomenon is
referred to as aquaplaning or hydro-
planing, and can lead to partial or com-
plete loss of traction, vehicle control
and braking effectiveness. Reduce your
speed on wet roads.<
Brake systemApprox. 300 miles (500 km) must
elapse before the brake pads and
rotors achieve the optimal pad-surface
and wear patterns required for trouble-
free operation and long service life later
on.
To break-in the separate parking brake
drums, apply the parking brake lightly
when coasting to a standstill (at a traffic
signal, for instance), provided that
traffic conditions allow you to do so.
To avoid corrosion, repeat this proce-
dure from time to time.
The brake lamps do not come on
when the parking brake is applied.
Vacuum for the brake system servo unit
on your BMW is available only when the
engine is running. When you move the
vehicle with the engine switched off Ð
when towing, for instance Ð substan-
tially higher levels of pedal force will be
required to brake the vehicle.< ClutchThe clutch will also begin to function
optimally after about 300 miles
(500 km). Engage the gears carefully
during the break-in period.

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OverviewControlsMaintenanceRepairsDataIndex
Driving notes Antilock Brake System
Brakes:
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.
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 phe-
nomenon is referred to as aquaplaning
or hydroplaning. It is characterized by a
partial or complete loss of contact
between the tires and the road surface.
The ultimate results are loss of steering
and braking control.
Driving through water:
When there is water on the roads, do
not drive in it if it is deeper than
1 ft (30 cm), and even then, only at
walking speed, otherwise the vehicle
can sustain damage to the engine, the
electrical systems and the transmission.
Rear parcel tray:
Do not place heavy or hard objects on
the rear parcel tray. These objects
could endanger vehicle occupants
during heavy brake applications or eva-
sive maneuvers.
Clothes hooks:
Hang items of clothing from the hooks
so that they will not obstruct the driver's
vision. Do not hang heavy objects on
the hooks. If you do so, they could
cause personal injury during braking or
evasive maneuvers.<
The conceptThe Antilock Brake System (ABS) keeps
the wheels from locking during braking,
thereby enhancing active driving safety.
With ABS, the shortest possible braking
distances are achieved under most
conditions (on straight-aways and in
curves, on asphalt, ice, wet road sur-
faces, etc.).Braking with ABSIf you are in a situation that requires full
braking, you will exploit the full benefits
of the ABS system if you apply max-
imum pedal pressure ("panic stop").
Pulsation at the brake pedal combined
with sounds from the hydraulic circuits
indicates to the driver that ABS is in its
active mode.

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Brake systemBrake fluid level If the brake fluid level is too low and
brake pedal travel has become notice-
ably longer, there may be a defect in
one of the two brake system's hydraulic
circuits.
Proceed to the nearest BMW
center. Higher brake application
pressure may be necessary under these
conditions, and the vehicle may exhibit
a slight tendency to pull to one side
when the brakes are applied. Braking
distances may also be longer. Please
remember to adapt your driving style
accordingly.<
Disc brakesLimited vehicle use, extended periods
with the vehicle parked or in storage,
and operating conditions in which
braking is restricted to gentle, low-
pressure applications will all increase
the tendency for corrosion to form on
the rotors; this is often accompanied by
a simultaneous accumulation of con-
tamination on the brake pads. The pads
must exert a certain minimal level of
pressure against the rotors for the disc
brakes' inherent self-cleaning effect to
remain effective; the pressure available
under the above conditions may not
provide adequate cleansing.
If the brake rotors are corroded, they
will tend to respond to braking with a
pulsating effect that even extended
brake applications will fail to cure.
When driving in heavy rain and on wet
roads 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
pose a hazard to you or to other road
users. The heat generated in this pro-
cess helps dry the pads and rotors to
ensure that your brake system will
respond with undiminished efficiency
when you need it.When descending steep hills and
extended grades, downshift to a gear
that will allow you to continue safely
with only a minimal amount of braking.
By minimizing the loads placed on the
brake system, this strategy helps
ensure that optimal brake system
response will remain available at all
times.
Do not coast with the clutch
depressed or with the transmission
or selector lever in Neutral. Do not coast
with the engine switched off. The engine
provides no braking effect when the
clutch is depressed and there is no
power-assist for braking or steering
when the engine is not running.
Never allow floor mats, carpets or any
other objects to protrude into the area
around the accelerator, clutch and brake
pedals and obstruct their movement.<
Brake pads
For your own safety: use only
brake pads that BMW has
approved for your particular vehicle
model. BMW cannot evaluate non-
approved brake pads to determine if
they are suited for use, and therefore
cannot ensure the operating safety of
the vehicle if they are installed.<

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1 Reservoir for brake fluid (under the
housing of the microfilter)145
2 Auxiliary terminal for
jump-starting1643 Engine oil dipstick142
4 Engine oil filler neck142
5 Coolant expansion tank1446 Reservoir for intensive-cleaning
system
*
141
7 Reservoir for windshield and
headlamp washer system
*
141
Engine compartment essentials
390de791