2004 MERCEDES-BENZ ML500 light

212 OperationDriving instructionsTelephones and two-way radios
Radio transmitters, such as a portable tele-
phone or a citizens band unit should only
be used inside the vehicle if they are con-
nected to an antenna that is installed on
the outside of the vehicle.
Refer to the radio transmitter operation in-
structions regarding use of an external an-
tenna.
Catalytic converter
Your Mercedes-Benz is equipped with
monolithic-type catalytic converters, an
important element in conjunction with the
oxygen sensors to achieve substantial con-
trol of the pollutants in the exhaust emis-
sions. Keep your vehicle in proper
operating condition by following our rec-
ommended maintenance instructions as
outlined in your Service Booklet.
Emission control
Certain engine systems serve to keep the
toxic components of the exhaust gases
within permissible legal limits.
These systems, of course, will function
properly only when maintained strictly ac-
cording to factory specifications. Any ad-
justments on the engine should, therefore,
be carried out only by qualified
Mercedes-Benz Light Truck Center autho-
rized technicians. Engine adjustments
should not be altered in any way. More-
over, the specified service jobs must be
Warning!
G
Never operate radio transmitters equipped
with a built-in or attached antenna (i.e. with-
out being connected to an external antenna)
from inside the vehicle while the engine is
running. Doing so could lead to a malfunc-
tion of the vehicle’s electronic system, pos-
sibly resulting in an accident and / or
personal injury.
!To prevent damage to the catalytic con-
verters, use only premium unleaded
gasoline in this vehicle.
Any noticeable irregularities in engine
operation should be repaired promptly.
Otherwise, excessive unburned fuel
may reach the catalytic converter,
causing it to overheat and start a fire.
Warning!
G
As with any vehicle, do not idle, park or op-
erate this vehicle in areas where combusti-
ble materials such as grass, hay or leaves
can come into contact with the hot exhaust
system, as these materials could be ignited
and cause a vehicle fire.

216 OperationAt the gas stationEngine oil level
More information on engine oil see “Engine
oil” (
page 218).Vehicle lighting
Check function and cleanliness. More in-
formation on replacing light bulbs can be
found in the “Practical hints” section
(
page 266).
Tire inflation pressure
More information on tire inflation pressure
can be found in the “Operation” section
(page 227).
!If you find that the brake fluid in the
brake fluid reservoir has fallen to the
minimum mark or below, have the
brake system checked for brake pad
thickness and leaks immediately. Noti-
fy an authorized Mercedes-Benz Light
Truck Center immediately. Do not add
brake fluid as this will not solve the
problem. For more information, see
“Practical Hints” (
page 245).

217 Operation
Engine compartment
Engine compartment
Hood
Opening
1Release lever

Pull release lever1 downwards.
The hood is unlocked. Handle2 pro-
trudes slightly from the radiator-grille.
If not, lift the hood slightly.
2Handle for opening the hood

Pull handle2 to its stop out of the
radiator-grille.

Pull up on the hood and then release it.
The hood will be automatically held
open at shoulder height by gas-filled
struts.
Warning!
G
Do not pull the release lever while the vehi-
cle is in motion. Otherwise the hood could
be forced open by passing air flow.
!To avoid damage to the windshield wip-
ers or hood, never open the hood if the
wiper arms are folded forward away
from the windshield.
Warning!
G
To help prevent personal injury, stay clear of
moving parts when the hood is open and the
engine is running. Make sure the hood is
properly closed before driving. When closing
the hood, use extreme caution not to catch
hands or fingers.
The radiator fan may continue to run for ap-
proximately 30 seconds or even restart af-
ter the engine has been turned off. Stay
clear of fan blades.


218 OperationEngine compartment
Closing
Let the hood drop from a height of ap-
proximately 1 ft (30 cm).
The hood will lock audibly.

Check to make sure the hood is fully
closed.
If you can raise the hood at a point
above the headlamps, then it is not
properly closed. Open it again and let it
drop with somewhat greater force.
Engine oil
The amount of oil your engine needs will
depend on a number of factors, including
driving style. Higher oil consumption can
occur when

the vehicle is new


the vehicle is driven frequently at
higher engine speeds
Engine oil consumption checks should only
be made after the vehicle break-in period.
Warning!
G
If you see flames or smoke coming from the
engine compartment, or if the coolant tem-
perature gauge indicates that the engine is
overheated, do not open the hood. Move
away from vehicle and do not open the hood
until the engine has cooled. If necessary,
call the fire department.Warning!
G
The engine is equipped with a transistorized
ignition system. Because of the high voltage
it is dangerous to touch any components (ig-
nition coils, spark plug sockets, diagnostic
socket) of the ignition system

with the engine running


while starting the engine


if ignition is “on” and the engine is
turned manually
Warning!
G
Be careful that you do not close the hood on
anyone.!Do not push the hood closed manually,
as this could damage it.
iDo not use any special lubricant addi-
tives, as these may damage the drive
assemblies. Using special additives not
approved by Mercedes-Benz will
restrict your warranty entitlement.
More information on this subject is
available at any Mercedes-Benz Light
Truck Center.


220 OperationEngine compartmentThe display
------
flashes in the
speedometer display, if a proper oil level
check cannot be performed.

If engine is at normal operating
temperature, wait five minutes before
repeating check procedure.

If engine is not yet at normal operating
temperature, wait 30 minutes before
repeating check procedure.
See the “Practical hints” section
(
page 253) if the low engine oil level
warning lamp in the instrument cluster
flashes.Checking engine oil level with the oil
dipstick
When checking the oil level the vehicle
must


be parked on level ground


be at normal operating temperature


have been stationary for at least five
minutes with the engine turned off
To check the engine oil level with the oil
dipstick, do the following:

Open the hood (
page 217).

Pull out oil dipstick1 (
page 221).

Wipe oil dipstick1 clean.

Fully insert oil dipstick1 into the
dipstick guide tube.

Pull out oil dipstick1 again after
approximately three seconds to obtain
accurate reading.
Oil dipstickThe oil level is correct when it is between
the lower (min) and upper (max) mark of
the oil dipstick.
iPerform the engine oil level check with
the dipstick if it cannot be completed
via the speedometer display
(page 220).
In this case we recommend that you
have the system checked at a
Mercedes-Benz Light Truck Center.
iThe engine oil level can be checked by
either the oil dipstick or via the
speedometer display in the instrument
cluster (
page 219). The amount of
engine oil needed is shown more
precisely in the speedometer display.

222 OperationEngine compartment
Screw filler cap2 back on filler neck.
More information on engine oil can be
found in the “Technical data” section
(
page 300) and (
page 301).
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 Light
Truck Center check the automatic trans-
mission.Coolant
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.
!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.
Warning!
G
In order to avoid any possibly serious burns:

Use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system,
or if the coolant temperature gauge indi-
cates that the coolant is overheated.


Do not remove pressure cap on coolant
reservoir if engine temperature is above
194°F (90°C). Allow engine to cool
down before removing cap. The coolant
reservoir contains hot fluid and is under
pressure.


Using a rag, slowly open the cap approx-
imately ½ turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out un-
der pressure.


Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.


223 Operation
Engine compartment
1Cap
2COLD LEVEL mark
The coolant level should reach the COLD
LEVEL mark2 in the reservoir.

Using a rag, turn the cap slowly approx-
imately one half turn to the left to re-
lease any excess pressure.

Continue turning the cap to the left and
remove it.

Add coolant as required.

Replace and tighten cap.
More information on coolant can be found
in the “Technical data” section
(
page 304).
Battery
The battery is located in the engine com-
partment.
The battery should always be sufficiently
charged in order to achieve its rated ser-
vice life. Refer to Service Booklet for bat-
tery maintenance intervals.
If you use your vehicle mostly for
short-distance trips, you will need to have
the battery charge checked more frequent-
ly.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 Light Truck
Center about steps you need to observe.
iIf the engine is already at its regular op-
erating temperature, the coolant may
be approximately 0.6 in (1.5 cm) above
the COLD LEVEL mark.
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.

226 OperationTires and wheels
Tires and wheelsSee your authorized Mercedes-Benz Light
Truck Center for information on tested and
recommended rims and tires for summer
and winter operation. They can also offer
advice concerning tire service and pur-
chase.
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 Light
Truck Center for information on tested and
recommended rims and tires for summer
and winter operation.
Important guidelines

Use only 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 or 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.
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 Light Truck Center for fur-
ther information. 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.