engine BMW 540I SEDAN 2003 Service Manual

142n
Engine oilChecking oil level1. Park the vehicle on a level surface
2. Switch the engine off after it has
reached normal operating tempera-
ture
3. After approx. 5 minutes, pull the dip-
stick out and wipe it off with a clean
lint-free cloth, paper towel, or similar
material
4. Carefully push the dipstick all the
way into the guide tube and pull it
out again
5. The oil level should be in between
the two marks on the dipstick.
As with fuel economy, oil consumption
is directly influenced by your driving
style and vehicle operating conditions.390de647
The oil volume between the two marks
on the dipstick corresponds to approx.
1.1 US quarts (1 liter). Do not fill beyond
the upper mark on the dipstick. Excess
oil will damage the engine.460de189
Adding engine oilWhile you should wait until the level has
dropped to just above the lower mark
before adding oil, you should never
allow the oil level to fall below this
mark.
BMW engines are designed to
operate without oil additives; the
use of additives could lead to damage
in some cases. This is also true for the
manual transmission, the automatic
transmission, the differential, and the
power steering system.<
Recommendation: have the oil changed
by your BMW center only.390de626

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OverviewControlsMaintenanceRepairsDataIndex
Engine oil
Continuous exposure to used oil
has caused cancer in laboratory
testing. For this reason, any skin areas
that come into contact with oil should
be thoroughly washed with soap and
water.
Always store oil, grease, etc., out of
reach of children. Comply with all
warning labels and information on lubri-
cant containers.<
Comply with the applicable envi-
ronmental laws regulating the dis-
posal of used oil.<
Specified engine oilsThe quality of the engine oil selected
has critical significance for the opera-
tion and service life of an engine.
Based on extensive testing, BMW has
approved only certain engine oils.
Use only approved "BMW High
Performance Synthetic Oil."
If you are unable to obtain "BMW High
Performance Synthetic Oil," you can
add small amounts of synthetic oil in
between oil changes. Only use oils with
the API SH specification or higher.
Ask your BMW center for details
concerning the specific "BMW
High Performance Synthetic Oil" or
"synthetic oils" which have been
approved.<
You can also call BMW of North
America at 1-800-831-1117 or visit the
website: www.bmwusa.com to obtain
this information.
Viscosity ratingsViscosity is the oilflow rating as estab-
lished in SAE classes.
The selection of the correct SAE class
depends on the climatic conditions in
the area where you typically drive your
BMW.
Approved oils are in SAE classes
5W-40 and 5W-30.<
These oils may be used for driving in all
ambient temperatures.

144n
Coolant
Do not add coolant to the cooling
system when the engine is hot. If
you attempt to do so, escaping coolant
can cause scalds.
To avoid the possibility of damage later
on, never use anything other than fac-
tory-approved, nitrite and amino-free
extended-duty antifreeze with corrosion
inhibitor. Your BMW center is familiar
with the factory specifications.
Antifreeze and anti-corrosion agents
are hazardous to health. You should
always store them in their original con-
tainers and in a location which is out of
reach of children.
Extended-duty antifreeze with corro-
sion inhibitor contains the inflammable
substance ethylene-glycol. For this
reason, do not spill antifreeze with cor-
rosion inhibitor on hot engine parts. It
could catch fire and cause burns.<
Checking coolant level and
adding coolantCorrect coolant level when the engine
is cold (approx. 687/206):
Unscrew the cap from the expansion
tank.
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 (refer to the arrow in the illustra-
tion), but no more than 0.8 in (2 cm)
above it Ð that is, up to the second mark
on the float (refer also to the schematic
diagram next to the filler neck).380de081
1. Start by turning the cap counter-
clockwise. Pause to allow any accu-
mulated pressure to escape, then
open
2. If the coolant is low, slowly add
coolant until the correct level is
reached Ñ do not overfill.
Comply with the applicable envi-
ronmental laws regulating the dis-
posal of extended-duty antifreeze with
corrosion inhibitor.<

145n
OverviewControlsMaintenanceRepairsDataIndex
Brake fluid
The warning lamp for the brake
system's hydraulic circuits
comes on/the message
"CHECK BRAKE FLUID"
appears in the Check Control:
brake fluid level too low.
To add brake fluidThe brake fluid reservoir is located
under the microfilter housing on the
driver's side of the vehicle. For adding
brake fluid or for determining and cor-
recting the cause of brake fluid loss,
consult your BMW center. Your BMW
center is familiar with the specifications
for factory-approved brake fluids
(DOT 4).
Brake fluid loss may result in extended
brake pedal travel. Should this occur,
refer to the notes on page 134.
Brake fluid is hygroscopic, that is,
it absorbs moisture from the air
over time.
In order to ensure the safety and reli-
ability of the brake system, have
the brake fluid changed every two years
by a BMW center. Refer also to the Ser-
vice and Warranty Information Booklet
(US models) or to the Warranty and
Service Guide Booklet (Canadian
models).
Brake fluid is hazardous to health and
damages the vehicle's paint. You
should always store it in its original
container and in a location which is out
of reach of children.
Do not spill the fluid and do not fill the
brake fluid reservoir beyond the MAX
mark. The brake fluid could ignite upon
contact with hot engine parts and
cause serious burns.<
Comply with the applicable envi-
ronmental laws regulating the dis-
posal of brake fluid.<

146n
The BMW Maintenance System has
been designed as a reliable means of
providing maximum driving and oper-
ating safety Ð and as cost-effectively as
possible for you.
Please keep in mind that regular main-
tenance is not only necessary for the
safety of your vehicle, but also plays a
significant role in maintaining its resale
value.
390us702
Service Interval DisplayWhile conventional systems rely on dis-
tance traveled alone to determine when
service is due, the BMW Maintenance
System has for years considered the
actual conditions under which the
vehicle operates, because mileage can
be accumulated in very different ways.
From a maintenance standpoint,
62,000 miles (100,000 km) accumulated
in short-distance urban driving are not
the equivalent of the same distance
covered at moderate speeds in long-
distance highway travel.
The BMW Maintenance System
includes the Engine Oil Service and
Inspections I and II.
Determining the maintenance intervals
according to the actual loads on the
vehicle covers every kind of operating
situation. However, even those who
drive only short distances Ð significantly
less than 6,000 miles (10,000 km) annu-
ally Ð should have the engine oil
changed at least every 2 years since oil
deteriorates over time, regardless of
use.
Service and Warranty Information
Booklet (US models) or Warranty
and Service Guide Booklet
(Canadian models)For additional information on mainte-
nance intervals and procedures, please
refer to the Service and Warranty Infor-
mation Booklet (US models) or the
Warranty and Service Guide Booklet
(Canadian models).
As a precaution against corrosion, it is
advisable to have the body checked for
damage from rocks or gravel at the
same time, depending upon operating
conditions.
Have your BMW center do the
maintenance and repair.
Be sure that all maintenance work is
confirmed in the Service and Warranty
Information Booklet (US models) or in
the Warranty and Service Guide
Booklet (Canadian models).
These entries will constitute your proof
that the vehicle has received regular
maintenance. They are also required in
the event of a warranty claim.<
The BMW Maintenance System

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Light-emitting diodes (LEDs)Light-emitting diodes installed behind
translucent lenses serve as the light
source for many of the controls and dis-
plays in your vehicle. The concept
behind their operation is related to that
employed for lasers, and they are offi-
cially designated as Class 1 light-emit-
ting diodes.
Do not remove the protective lens
and avoid staring directly at the
unfiltered beam for extended periods
(several hours), as inflammation of the
iris could result.<
California laws require us to state the
following warning:
Engine exhaust, some of its con-
stituents, and certain vehicle com-
ponents contain or emit chemicals
known to the State of California to
cause cancer and birth defects and
reproductive harm. In addition, certain
fluids contained in vehicles and certain
products of component wear contain or
emit chemicals known to the State of
California to cause cancer and birth
defects or other reproductive harm.
Battery posts, terminals and related
accessories contain lead and lead
compounds. Wash your hands after
handling.
Used engine oil contains chemicals that
have caused cancer in laboratory ani-
mals. Always protect your skin by
washing thoroughly with soap and
water.<
Technical modifications California Proposition 65 Warning

148n
OBD interface socketThe Onboard Diagnostic (OBD) inter-
face socket is located on the left of the
driver's side at the bottom of the instru-
ment panel and under a cover. The
cover has the letters "OBD" on it.
The purpose of the OBD system is to
ensure proper operation of the emis-
sion control system for the vehicle's
lifetime. The system monitors emis-
sions-related components and sys-
tems to detect deterioration and mal-
function.390us739
An illuminated lamp informs you
of the need for service, not of
the need to stop the vehicle.
However, the systems should be
checked by your BMW center at the
earliest possible opportunity.
Under certain conditions, the indicator
will blink or flash. This indicates a rather
severe level of engine misfire. When
this occurs, you should reduce speed
and consult the nearest BMW center as
soon as possible. Severe engine misfire
over only a short period of time can
seriously damage emission control
components, especially the catalytic
converter.
Service Engine Soon warning
lamp for Canadian models.
When the filler cap is not properly
tightened, the OBD system can
detect the vapor leak and the indicator
will light up. If the filler cap is subse-
quently tightened, the indicator should
go out within a few days.<

153n
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Lamps and bulbsThe lamps and bulbs are essential fac-
tors contributing to the safety of your
vehicle. For this reason, you should
follow the instructions below carefully
when replacing a bulb. If you are not
familiar with any of the procedures,
consult your BMW center.
Do not touch the glass portion of a
new bulb with your bare hands
since even small amounts of impurities
burn into the surface and reduce the
service life of the bulb. Use a clean
cloth, paper napkin, or a similar mate-
rial, or hold the bulb by its metallic
base.<
A replacement bulb set is available from
your BMW center.
Whenever working on the elec-
trical system, switch off the elec-
trical accessory you are working on or
disconnect the cable from the negative
terminal of the battery. Failure to do this
could result in short circuits.
To prevent injuries and damage,
comply with any instructions provided
by the bulb manufacturer.<
The right side of the engine compart-
ment.
1 Low beams
2 High beams
For checking and adjusting head-
lamp aim, please contact your
BMW center.< Low and high beamsH7 bulb, 55 watt
The bulb is pressurized. There-
fore, you should always wear
safety glasses and protective gloves.
Failure to observe these precautions
can result in physical injury if the bulb
breaks.< 390de767
1. Turn the bulb holder to the left
(arrow) and remove
2. Remove and replace the bulb.
When cleaning the headlamps,
please observe the following:
>Do not wipe dry (scratches). Never
use abrasives or strong solvents to
clean the covers
>Remove dirt and contamination (such
as insects) by soaking with BMW Car
Shampoo and then rinsing with plenty
of water
>Always use a deicer spray to remove
accumulated ice and snow Ð never
use a scraper.<

158n
Lamps and bulbs Changing a wheelLicense plate lamps5 watt bulb
1. Insert a screwdriver into the slot and
press to the left (arrow); this disen-
gages the lamp
2. Remove the lamp and replace the
bulb.394de772
Safety measures in the event of a
flat tire or wheel change:
Stop the vehicle as far as possible from
passing traffic. Park on a firm, flat, sur-
face. Switch on the hazard warning
flashers.
Turn the steering wheel to the straight-
ahead position, remove the key and
engage the steering lock. Shift into 1st
or reverse (selector lever in Park with
automatic transmission) and engage
the parking brake.
All passengers should be outside the
vehicle and well away from your imme-
diate working area (behind a guardrail,
for instance).
If necessary, set up your warning tri-
angle or portable hazard warning lamp
on the roadside at an appropriate dis-
tance from the rear of the vehicle.
Comply with all safety guidelines and
regulations.
Change the wheel only on a level, firm
surface which is not slippery. Avoid
jacking the vehicle up on a soft or slip-
pery surface (snow, ice, very smooth
surfaces, etc.), since it could slide side-
ways.
Position the jack on a firm support sur-
face.
Do not place wooden blocks or similar
objects under the jack. If this is done,
the jack might not be able to reach its
full support capacity because of the
limited height.
Do not lie under the vehicle or start the
engine when the vehicle is supported
by the jack Ð risk of fatal injury.<

162n
Battery Fuses
Battery posts, terminals and other
components contain lead and lead
compounds. Wash hands after han-
dling.<
Battery careThe battery is maintenance-free, that is,
the original electrolyte will normally last
for the service life of the battery under
moderate climatic conditions.
For all questions that regard the
battery, please consult your BMW
center. The battery is completely main-
tenance-free; the following section is
provided for your information only.<
Do not disconnect the battery
when the engine is running, as the
ensuing voltage surge would damage
the vehicle's onboard electronics.<
Charging the batteryWhen charging the battery in the
vehicle, leave the engine off at all times.
Connect the charge cables to the termi-
nals in the engine compartment (for ter-
minal locations, refer to "Jump-starting"
on page 164).
Return used batteries to a recy-
cling point or your BMW center.
Maintain the battery in an upright posi-
tion for transport and storage. Secure
the battery against tilting during trans-
port.<
In the glove compartmentOpen the glove compartment and turn
the two white quick-release fasteners
to the left.390de085