Page 365 of 489

364 Practical hintsWhat to do if …?Problem
Possible cause/consequence
Suggested solution
•
The red coolant warning lamp
comes on when the engine is
running.
There is insufficient coolant in the reservoir.
Add coolant to prevent engine from
overheating (
page 314).
If this warning lamp comes on frequently,
there is a leak in the cooling system.
Have the cooling system checked.
If the coolant level is correct, the electric ra-
diator fan may be broken.
If the coolant temperature is below
257 °F (125 °C), you can continue
driving to the nearest authorized
Mercedes-Benz Center.
Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.
•
The red coolant warning lamp
comes on while driving and you
hear a warning sound.
The coolant temperature has exceeded
257 °F (125 °C).
Stop as soon as possible and allow
the engine and coolant to cool down.
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 open-
ing the hood. Stay away from the engine if
you see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.
Page 386 of 489

385 Practical hints
What to do if …?
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display symbol
Display message
Possible cause/consequence
Possible solution
•
Coolant
Stop, engine off
The coolant is too hot.
Stop the vehicle in a safe location or
as soon as it is safe to do so and turn
off the engine.
Only start the engine again after the
message disappears. You could other-
wise damage the engine.
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 open-
ing the hood. Stay away from the engine if
you see or hear steam coming from it.
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). Doing so may cause serious
engine damage which is not covered by
the Mercedes-Benz Limited Warranty.
Page 387 of 489
386 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause/consequence
Possible solution
•
Coolant
Stop, engine off
The 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.
Drive immediately to the nearest authorized
Mercedes-Benz Center.
Coolant
Visit workshop
The cooling fan for the coolant is mal-
functioning.
Observe the coolant temperature display.
Have the fan replaced as soon as possible.
Page 388 of 489

387 Practical hints
What to do if …?
Display symbol
Display message
Possible cause/consequence
Possible solution
4
Check gas cap
See Oper.’s Man.
A loss of pressure has been detected in
the fuel system. The fuel cap may not be
closed properly or the fuel system may be
leaky.
Check the fuel cap (
page 305).
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked by an
authorized Mercedes-Benz Center.
G
Display malfunction
Visit workshop
The instrument cluster display is malfunc-
tioning.
Continue driving with added caution.
Visit an authorized Mercedes-Benz
Center as soon as possible.
The displays for several systems have
malfunctioned. Some systems them-
selves may also have malfunctioned.
Have the electronic systems checked
by an authorized Mercedes-Benz Cen-
ter.
±
Display defective
Visit workshop
Certain electronic systems are unable to
relay information to the control system.
The following systems may have failed:
Coolant temperature display
Tachometer
Cruise control display
Have the electronic systems checked
by an authorized Mercedes-Benz Cen-
ter.
J
Doors open
You are attempting to drive with one or
more doors open.
Close the doors.
Page 453 of 489
452 Technical dataFuels, coolants, lubricants, etc.CapacitiesVehicle components and their respective
lubricants must match. Therefore only use
products tested and approved by
Mercedes-Benz.Please refer to the Factory Approved Ser-
vice Products pamphlet, or inquire at your
Mercedes-Benz Center.
Model
Capacity
Fuels, coolants, lubricants, etc.
Engine with oil filter
CLK 350
CLK 500
8.5 US qt (8.0 l)
7.9 US qt (7.5 l)
Approved engine oils
Automatic transmission
CLK 350
CLK 500
9.0 US qt (8.5 l)
9.0 US qt (8.5 l)
MB Automatic Transmission Fluid
Rear axle
CLK 350
CLK 500
1.16 US qt (1.1 l)
1.69 US qt (1.6 l)
Hypoid gear oil SAE 85 W 90
Power steering
approx. 1.1 US qt (1.0 l)
MB Power Steering Fluid (Pentosin
CHF 11S)
Front wheel hubs
approx. 3.0 oz (85 g) each
High temperature roller bearing grease
Brake system
0.64 US qt (0.6 l)
MB Brake Fluid (DOT 4+)
Page 454 of 489
453 Technical data
Fuels, coolants, lubricants, etc.
Model
Capacity
Fuels, coolants, lubricants, etc.
Cooling system
CLK 350
CLK 500
approx. 10.5 US qt (10.0 l)
approx. 12.8 US qt (12.0 l)
MB 325.0 Anticorrosion/Antifreeze
Agent
Fuel tank
including a reserve of
16.35 US gal (62.0 l)
2.11 US gal (8.0 l)
Premium unleaded gasoline:
Minimum Posted Octane 91
(Avg.of96RON/86MON)
Air conditioning system
R-134a refrigerant and special PAG lu-
bricant oil (never R-12)
Windshield washer and
headlamp cleaning system*
6.4 US qt (6.0 l)
MB Windshield Washer Concentrate
1
1Use MB Windshield Washer Concentrate “MB SummerFit” and water for temperatures above freezing point or MB Windshield Washer Concentrate “MB SummerFit”
and commercially available premixed windshield washer solvent / antifreeze for temperatures below freezing point. Follow suggested mixing ratios (page 459).
Page 460 of 489

459 Technical data
Fuels, coolants, lubricants, etc.
Windshield washer system and headlamp cleaning system*
Both the windshield washer and headlamp
cleaning system are supplied from the
windshield washer fluid reservoir.
The washer fluid reservoir has a capacity of
approx. 6.4 US qt (6.0 l).
Refill the reservoir with MB Windshield
Washer Concentrate “MB SummerFit”
and water (or concentrate and com-
mercially available premixed wind-
shield washer solvent / antifreeze,
depending on ambient temperatures).Windshield and headlamp washer fluid
mixing ratio
For temperatures above freezing point, use
MB Windshield Washer Concentrate
“MB SummerFit” and water:
1 part “MB SummerFit” to 100 parts
water
(1.34 fl oz [40 ml] “MB SummerFit” to
1 gallon [4.0 l] water)
For temperatures below freezing point, use
MB Windshield Washer Concentrate
“MB SummerFit” and commercially avail-
able premixed windshield washer
solvent / antifreeze:
1 part “MB SummerFit” to 100 parts
solvent
(1.34 fl oz [40 ml] “MB SummerFit” to
1 gallon [4.0 l] solvent)
Warning!
G
Washer solvent/antifreeze is highly flam-
mable. Do not spill washer
solvent/antifreeze on hot engine parts, be-
cause it may ignite and burn. You could be
seriously burned.
Page 464 of 489

463 Technical terms
Instrument cluster
The displays and indicator/warning
lamps in the driver’s field of vision, in-
cluding the tachometer, speedometer,
coolant temperature indicator and fuel
display.
KEYLESS-GO*
System for entering and operating the
vehicle without the use of a SmartKey.
Kickdown
Depressing the accelerator past the
point of resistance shifts the transmis-
sion down to the lowest possible gear.
This very quickly accelerates the vehi-
cle and should not be used for normal
acceleration needs.
Kilopascal (kPa)
(
page 343)
Locking knob
Knob on the door which indicates
whether the door is locked or un-
locked. Pushing the locking knob down
on the driver’s or passenger door from
inside will lock that door.Maintenance System (U.S. vehicles)
Maintenance service indicator in the
multifunction display that informs the
driver when the next vehicle mainte-
nance service is due. The Maintenance
System in your vehicle tracks distance
driven and the time elapsed since your
last maintenance service, and calls for
the next maintenance service
accordingly.
Maximum load rating
(
page 343)
Maximum loaded vehicle weight
(page 343)
Maximum tire inflation pressure
(page 343)
Memory function*
Used to store three individual seat,
steering wheel and exterior mirror
positions.Menu
The control system displays are ar-
ranged in menus. Each menu contains
a number of commands for particular
systems.
MON
(M
otor O
ctane N
umber)
The Motor Octane Number for gasoline
as determined by a standardized meth-
od. It is an indication of a gasoline's
ability to resist undesired detonation
(knocking). The average of both the
MON (Motor Octane Number) and
->RON (Research Octane Number) is
posted at the pump, also known as
ANTI-KNOCK INDEX.
MOE
(M
ercedes-Benz O
riginal E
xtended
equipment tires)
Tires with limited run-flat characteris-
tics. The MOExtended system allows
you to continue driving your vehicle
even if there is a total loss of pressure
in one or more tires.