Page 511 of 723

508 Operation
Driving instructions
Coolant temperature
During severe operating conditions,
e.g. stop-and-go traffic, the coolant tem-
perature may rise close to approximately
248°F (120°C).
The engine should not be operated with
the coolant temperature over 248°F
(120°C). Doing so may cause serious en-
gine damage which is not covered by the
Mercedes-Benz Limited Warranty.
Warning!G
Inhalation of exhaust gas is hazardous to
your health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause un-
consciousness and possible death.
Do not run the engine in confined areas
(such as a garage) which are not properly
ventilated. If you think that exhaust gas
fumes are entering the vehicle while driving,
have the cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one win-
dow fully open at all times.
Warning!G
Driving when your engine is badly over-
heated can cause some fluids, which
may have leaked into the engine com-
partment, to catch fire. You could be se-
riously burned.
Steam from an overheated engine can
cause serious burns and can occur just
by opening the hood. Stay away from
the engine if you see or hear steam com-
ing from it.
Stop the vehicle in a safe location away from
other traffic. Turn off the engine, get out of
the vehicle and do not stand near the vehicle
until the engine has cooled down.
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Page 514 of 723

511 Operation
At the gas station
Check regularly and before a long trip
Example illustration from CL 550
1Coolant level
2Brake fluid
3Windshield washer and headlamp
cleaning systemWindshield washer system and head-
lamp cleaning system
For more information on refilling the wash-
er reservoir, see “Windshield washer sys-
tem and headlamp cleaning system”
(
page 519).
Coolant
For more information on coolant, see
“Coolant level” (
page 518) and see “Fu-
els, coolants, lubricants, etc.”
(
page 684).
Brake fluid
For information on brake fluid, see “Brake
fluid” (
page 687)Engine oil level
For more information on engine oil, see
“Engine oil” (
page 513).
Vehicle lighting
Check function and cleanliness. For more
information on replacing light bulbs, see
“Replacing bulbs” (
page 641).
For more information, see “Lighting”
(
page 363).
Tire inflation pressure
For information on tire inflation pressure,
see “Checking tire inflation pressure”
(
page 530).
iOpening the hood (page 512).
!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. Notify an
authorized Mercedes-Benz Center immediately.
Do not add brake fluid as this will not solve the
problem. For more information, see “Practical
hints” (
page 569) and (page 596).
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Page 516 of 723

513 Operation
Engine 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 down. If neces-
sary, 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
cranked manually
Warning!G
When closing the hood, use extreme caution
not to catch hands or fingers. Be careful that
you do not close the hood on anyone.
Make sure that the hood is securely en-
gaged before driving off. Do not continue
driving if the hood can no longer engage af-
ter an accident, for example. The hood could
otherwise come loose while the vehicle is in
motion and endanger you and/or others.
!Do not use any special lubricant additives,
as these may damage the drive assemblies. Us-
ing special additives not approved by
Mercedes-Benz may cause damage not covered
by the Mercedes-Benz Limited Warranty.
More information on this subject is available at
any Mercedes-Benz Center.
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Page 521 of 723

518 Operation
Engine compartment
Coolant level
The engine coolant is a mixture of water
and anticorrosion/antifreeze.
When checking the coolant level,
the vehicle must be parked on level
ground
the coolant temperature must be
below 158°F (70°C)
The coolant expansion tank is located on
the passenger side of the engine compart-
ment.
Example illustration from CL 550
1Cap
2Coolant expansion tank
Using a rag, turn cap1 slowly approx-
imately one half turn counterclockwise
to release any excess pressure.
Continue turning the cap counterclock-
wise and remove it.
The coolant level is correct if the level
for cold coolant: reaches the white
marking (plastic bridge) inside the cool-
ant expansion tank
for warm coolant: is approximately
0.6 in (1.5 cm) higher
Add coolant as required.
Replace and tighten cap1.
For more information on coolant, see the
“Technical data” section (
page 689).
Warning!G
In order to avoid potentially 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 coolant temperature is
above 158°F (70°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 1/2 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.
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Page 612 of 723
609 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Coolant,
please refill
See Oper. ManualThe coolant level is too low.Add coolant (page 518).
If you have to add coolant frequently, have
the cooling system checked by an authorized
Mercedes-Benz Center.
Warning!G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You could be seriously burned.
!Do not ignore the low engine coolant level
warning. Extended driving with the message and
symbol displayed may cause serious engine
damage not covered by the Mercedes-Benz Lim-
ited Warranty.
Do not drive without a sufficient amount of cool-
ant in the cooling system. The engine will over-
heat, causing major engine damage.
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Page 613 of 723

610 Practical hints
What to do if …?
During severe operating conditions,
e.g. stop-and-go traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display Possible cause/consequencePossible solution
Coolant level
Stop vehicle!
Switch engine offThe coolant is too hot. Stop the vehicle in a safe location or as soon
as it is safe to do so and immediately turn off
the engine.
Only start the engine again after the message
disappears. You could otherwise damage the
engine.
Observe the coolant temperature gauge in
the instrument cluster (
page 30).
Warning!G
Driving when your engine is overheated
can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously
burned.
Steam from an overheated engine can
cause serious burns which can occur
just by opening the engine hood. Stay
away from the engine if you see or hear
steam coming from it.
Stop the vehicle in a safe location away from
other traffic. Turn off the engine, get out of
the vehicle and do not stand near the vehicle
until the engine has cooled down.!The engine should not be operated with the
coolant temperature above 248°F (120°C). Do-
ing so may cause serious engine damage which
is not covered by the Mercedes-Benz Limited
Warranty.
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Page 614 of 723
611 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Coolant level
Stop vehicle!
Switch engine offThe poly-V-belt could be broken.Stop the vehicle in a safe location or as soon
as it is safe to do so and immediately turn off
the engine.
Check the poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise the en-
gine will overheat due to an inoperative water
pump which may result in damage to the en-
gine.
Notify an authorized Mercedes-Benz Center.
If it is intact:
Do not continue to drive the vehicle with this
message displayed. Doing so could result in
serious engine damage that is not covered by
the Mercedes-Benz Limited Warranty.
Observe the coolant temperature gauge in
the instrument cluster (
page 30).
(Continued on next page)
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Page 615 of 723
612 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Coolant level
Stop vehicle!
Switch engine offRestart the engine.
If this message disappears from the multi-
function display:
Drive immediately to the nearest autho-
rized Mercedes-Benz Center.
If this message does not disappear from the
multifunction display:
Call Roadside Assistance.
The cooling fan for the coolant is malfunc-
tioning.Observe the coolant temperature gauge in
the instrument cluster (
page 30).
Have the fan replaced as soon as possible.
You are driving with one or both doors
open.
The display symbol shows you which doors
are open.Close the doors.
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