2004 MERCEDES-BENZ E320 RON

279 Operation
At the gas station

Replace the fuel cap by turning it to the
right.
You will hear when the fuel cap is tight-
ened.

Close the fuel filler flap.
Check regularly and before a long trip
1Windshield washer and headlamp
cleaning system*
For more information on refilling the
reservoir (
page 288).
2Brake fluid
More information on brake fluid can be
found in the “Technical data” section
(
page 403).
3Coolant level
More information on the coolant level
(page 285).
Warning!
G
Overfilling of the fuel tank may create pres-
sure in the system which could cause a gas
discharge. This could cause the gas to spray
back out when removing the fuel pump noz-
zle, which could cause personal injury.
iUse only premium unleaded gasoline
with a minimum Posted Octane Rating
of 91 (average of 96 RON / 86 MON).
Information on gasoline quality can
normally be found on the fuel pump.
More information on gasoline can be
found in the Factory Approved Service
Products Pamphlet.iLeaving the engine running and the fuel
cap open can cause the ? lamp to
illuminate.

285 Operation
Engine compartment
1Filler cap
Unscrew filler cap1 from filler neck.

Add engine oil as required. Be careful
not to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.

Screw filler cap1 back on filler neck.
More information on engine oil can be
found in the “Technical data” section
(
page 400) and (
page 403).
Transmission fluid level
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Center
check the transmission.Coolant level
The engine coolant is a mixture of water
and anticorrosion/antifreeze. To check
the coolant level, the vehicle must be
parked on level ground and the engine
must be cool.
The coolant expansion tank is located on
the driver’s side of the engine compart-
ment.
!Excess oil must be siphoned or drained
off. It could cause damage to the
engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.

287 Operation
Engine compartment
Battery
Your vehicle is equipped with two batter-
ies:

Auxiliary battery (located in the engine
compartment).


Main battery (starter and electrical
consumers; located in the trunk).
These batteries should always be suffi-
ciently charged in order to achieve their
rated service life. Refer to Service Booklet
for battery maintenance intervals.
If you use your vehicle mostly for short-dis-
tance trips, you will need to have the bat-
tery charge checked more frequently.
When replacing batteries, always use bat-
teries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Center about
steps you need to observe.Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
G
Observe all safety instructions
and precautions when handling
automotive batteries.
A
Risk of explosion
D
Keep flames or sparks away
from battery. Do not smoke.
B
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
In case it does, immediately
flush affected area with clear
water and seek medical help if
necessary.
E
Wear eye protection.
C
Keep children away.
F
Follow the instructions in this
Operator's Manual.

289 Operation
Tires and wheels
Tires and wheels
See your authorized Mercedes-Benz Cen-
ter for information on tested and recom-
mended rims and tires for summer and
winter operation. They can also offer ad-
vice concerning tire service and purchase.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on
retreads. Mercedes-Benz can therefore
not assure the operating safety of the vehi-
cle when such tires are used.
See your authorized Mercedes-Benz Cen-
ter for information on tested and recom-
mended rims and tires for summer and
winter operation.
Important guidelines

Only use sets of tires and rims of the
same type and make.


Tires must be of the correct size for the
rim.


Break in new tires for approximately
60 miles (100 km) at moderate
speeds.


Regularly check the tires and rims for
damage. Dented or bent rims can
cause tire pressure loss and damage to
the tire beads.


If vehicle is heavily loaded, check tire
pressure and correct as required.


Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths under
1⁄8in (3 mm).


When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!
G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See your authorized
Mercedes-Benz Center for further informa-
tion. If incorrectly sized rims and tires are
mounted:

The wheel brakes or suspension compo-
nents can be damaged


The correct operating clearance of the
wheels and the tires are no longer guar-
anteed
Warning!
G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, use only genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can re-
sult in the bolts loosening and possibly an
accident.

291 Operation
Tires and wheels
Tire pressure changes by approximately
1.5 psi (0.1 bar) per 18°F (10°C) of air
temperature change. Keep this in mind
when checking tire pressure where the
temperature is different from the outside
temperature.
Tire temperature and tire pressure are also
increased while driving, depending on the
driving speed and the tire load.
Check the spare tire periodically for condi-
tion and inflation. Spare tires will age and
become worn over time even if never used,
and thus should be inspected and replaced
when necessary.Checking tire pressure electronically*
The tire inflation pressure monitor only
functions on wheels that are equipped with
the proper electronic sensors. It monitors
the tire inflation pressure, as selected by
the driver, in all four tires. A warning is is-
sued to alert you to a decrease in pressure
in one or more of the tires.
Tire pressure inquiries are made using the
multifunction display (
page 129).The
present inflation pressures are displayed
only after a few minutes’ travel time.You can select the unit of measure used for
the tire inflation pressure by changing the
setting in the control system (
page 143).

Switch on ignition.

Press the k button until the current
inflation pressures for each tire appear
in the multifunction display.
Warning!
G
Follow recommended inflation pressures.
Do not overinflate tires. Overinflated tires
can result in sudden deflation (blowout) be-
cause they are more likely to become punc-
tured or damaged by road debris, potholes,
etc.
Do not underinflate tires. Underinflated tires
wear unevenly, adversely affect handling
and fuel economy, and are more likely to fail
from being overheated.
Do not overload the tires by exceeding the
specified vehicle capacity weight (as indicat-
ed by the label on the pillar in the driver’s
door opening). Overloading the tires can
overheat them, possibly causing a blowout.
iPossible differences between the read-
ings of a tire pressure gauge of an air
hose, e.g. gas station equipment, and
the vehicle’s control system can occur.
The readings issued by the control sys-
tem are more precise.

292 OperationTires and wheels
Activating the tire inflation pressure
monitor
You must activate the tire inflation pres-
sure monitor in the following cases:

If you have changed the tire pressure


If you have replaced the wheels or tires


If you have installed new wheels or
tires

Make sure the tire pressure is correctly
set.

Press buttonè orÿ on the mul-
tifunction steering wheel repeatedly
until the standard display menu ap-
pears in the multifunction display
(page 134).

Press the j or k button repeat-
edly until you see the current inflation
pressures for each tire appear in the
display
or the following message appears in
the displayTire pres. monitor

Pres. display after driving a few
mins. Reactivate using R button
Warning!
G
The tire inflation pressure monitor does not
indicate a warning for wrongly selected in-
flation pressures. Always adjust tire inflation
pressure according to the label on the fuel
filler cap.
The tire inflation pressure monitor is not
able to issue a warning due to a sudden dra-
matic loss of pressure (e.g. tire blowout
caused by a foreign object). In this case
bring the vehicle to a halt by carefully apply-
ing the brakes and avoiding abrupt steering
maneuvers.iOperating radio transmission equip-
ment (e.g. wireless headsets, two-way
radios) in or near the vehicle could
cause the tire inflation pressure moni-
tor to malfunction.
iIf transporting a deflated road wheel or
additional wheel sensors in the vehicle,
the tire inflation pressure monitor
should not be reactivated until the de-
flated wheel or additional wheel sen-
sors have been removed from the
vehicle. Otherwise, the deflated wheel
or additional sensors could cause the
tire inflation pressure monitor system
to malfunction.

293 Operation
Tires and wheels

Press the reset button (
page 22).
The following message will appear in
the multifunction display:
Check current tire pres.?


Press the æ button.
The following message will appear in
the multifunction display field:Tire pres. monitor acitvated

The tire inflation pressure monitor will
now monitor the tire inflation pressure
values of all four tires.
The following message will appear in
the multifunction display field:
Tire pres. monitor
Pres. display after driving a few
mins. Reactivate using R buttonThis display appears until the individual
inflation pressure values are matched
with the tires. The individual values are
then displayed (
page 340).If you wish to cancel activation:

Press the ç button.
If the following message appears in the
multifunction display field:
Reactivate tire

Pres. monitor

or
Tire pres.

Check tires!


Check the tire inflation pressures and
correct them if necessary.

Reactivate the tire inflation pressure
monitor.
Rotating wheels
On vehicles with the same wheel size all
around, wheels can be rotated every 3000
to 6000 miles (5 000 to 10 000 km), or
sooner if necessary, according to the de-
gree of tire wear. The same direction of tire
rotation must be retained.
Rotate the wheels before the characteris-
tic tire wear pattern becomes visible
(shoulder wear on front wheels and tread
center wear on rear wheels).
Thoroughly clean the inner side of the
wheels after each rotation. Check and en-
sure proper tire inflation pressure.Warning!
G
Rotate front and rear wheels only if they are
of the same size.

294 OperationTires and wheels
For information on wheel change, see the
“Practical hints” section (
page 350) and
(
page 366).
!If your ve hic le i s eq uip pe d with a ti re i n-
flation pressure monitor*, there are
electronic components built into the
wheel.
Do not use mounting tools in the area
of the valve as they could damage the
electronic components.
To prevent damage or incorrect instal-
lation, have the tires changed at an au-
thorized Mercedes-Benz Center.
Warning!
G
Have the tightening torque checked after
changing a wheel. Wheels could become
loose if not tightened with a torque of
96 lb-ft (130 Nm).
Use only genuine Mercedes-Benz wheel
bolts specified for your vehicle's rims.