2008 MERCEDES-BENZ CLS63AMG cooling

201 Controls in detail
4-zone automatic climate control
Air conditioning
The cooling function, only operational
when the engine is running, cools the vehi-
cle interior down to the selected tempera-
ture. The cooling function also
dehumidifies the air in the vehicle interior,
thus preventing the windows from fogging
up.Deactivating
It is possible to deactivate the air condi-
tioning (cooling) function of the climate
control system. The air in the vehicle will
then no longer be cooled or dehumidified.
Press button2 (page 190) or
(
page 191).
The indicator lamp on the button goes
out.
Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condition-
ing.
Press button2 (page 190) or
(
page 191) again.
The indicator lamp on the button
comes on.
The air conditioning uses the refrigerant
R134a. This refrigerant is free of CFCs
which are harmful to the ozone layer.Residual heat and ventilation
(Canada only)
With the engine switched off, it is possible
to continue to heat or ventilate the interior
for up to 30 minutes. This feature makes
use of the residual heat produced by the
engine.
iCondensation may drip out from underneath
the vehicle. This is normal and not an indication
of a malfunction.
Warning!G
If you turn off the cooling function, the
vehicle will not be cooled when weather
conditions are warm. The windows can fog
up more quickly. Window fogging may
impair visibility and endanger you and
others.
!If the air conditioning cannot be turned on
again, this indicates that the air conditioning is
losing refrigerant. The compressor has turned it-
self off.
Have the air conditioning checked at the nearest
authorized Mercedes-Benz Center.
iIf you switch on the residual heat function
when temperatures are high, only the ventilation
will be switched on.
iRegardless of the selected air volume, the
blower operates at low speed.

290 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 driver’s side of the engine compart-
ment.
1Marking bar in the expansion tank
2Cap
3Coolant expansion tank
Using a rag, turn cap2 slowly approx-
imately one half turn counterclockwise
to release any excess pressure.
Continue turning cap2 counterclock-
wise and remove it.
The coolant level is correct if the level:

for cold coolant: reaches marking
bar1 in expansion tank3

for warm coolant: is approximately
0.6 in (1.5 cm) higher
Add coolant as required.
Replace and tighten cap2.
For more information on coolant, see the
“Technical data” section (
page 452).
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
under 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.

350 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
DThe red coolant temperature
warning lamp comes on when
the engine is running.There is insufficient coolant in the reservoir.
If this warning lamp comes on frequently,
there is a leak in the cooling system.
If the coolant level is correct, the electric
radiator fan may be broken.Immediately add coolant to prevent
engine from overheating
(
page 290).
Have the cooling system checked.
If the coolant temperature is below
248°F (120°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.
DThe red coolant temperature
warning lamp comes on while
driving and you hear a warning
sound.The coolant temperature has exceeded
248°F (120°C).Stop in a safe location as soon as pos-
sible and allow the engine and coolant
to cool down.
Warning!G
Driving when your engine is badly overheat-
ed 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 engine hood. Stay away from the en-
gine 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.

375 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
(USA only)
ú
(Canada only)
±
Service RequiredThere may be a malfunction in the:

fuel injection system

ignition system

exhaust system

fuel system
Have the measuring system checked
by an authorized Mercedes-Benz
Center.
H Top Up
Coolant
See Operator’s Man.The coolant level is too low.Add coolant (page 290).
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 sufficient amount of coolant
in the cooling system. The engine will overheat
causing major engine damage.

378 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
DThe cooling fan for the coolant is
malfunctioning.Observe the coolant temperature indicator in the
instrument cluster (
page 26).
If the coolant temperature is under 248°F (120°C),
you may continue driving to an authorized
Mercedes-Benz Center.
Avoid placing heavy loads on the engine (e.g. by
driving uphill) as well as stop-and-go traffic.
Have the fan replaced as soon as possible.
± Display Malfunction
Service RequiredCertain electronic systems are
unable to relay information to
the control system. The follow-
ing systems may have failed:

Coolant temperature display

Tachometer

Cruise control display
Have the electronic systems checked by an autho-
rized Mercedes-Benz Center.
Engine
ServiceThere may be a malfunction in:

the fuel injection system

the ignition system

the exhaust system
Have the engine checked as soon as possible by an
authorized Mercedes-Benz Center.

449 Technical data
Fuels, coolants, lubricants etc.
ModelCapacityFuels, coolants, lubricants etc.
Power steeringCLS 550approx. 1.0 US qt (0.9 l)MB Power Steering Fluid (Chevron
Texaco PSF 9109)1
1For detailed information, please refer to the Factory Approved Service Products pamphlet (USA only) or contact an authorized Mercedes-Benz Center.
CLS 63 AMGapprox. 1.3 US qt (1.2 l)
Front wheel hubsCLS 550approx. 3.0 oz (85 g) eachHigh temperature roller bearing grease
CLS 63 AMGapprox. 3.2 oz (90 g) each
Brake systemAll models0.63 US qt (0.6 l)MB Brake Fluid (DOT 4+)
Cooling systemCLS 55011.9 US qt (11.3 l)MB 325.0 Anticorrosion/Antifreeze
CLS 63 AMG12.5 US qt (11.8 l)
Fuel tankAll models21.12 US gal (80.0 l)Premium unleaded gasoline:
Minimum Posted Octane 91
(Avg. of 96 RON/86 MON)
including a reserve ofCLS 5502.38 US gal (9.0 l)
CLS 63 AMG3.7 US gal (14.0 l)
Air conditioning systemAll modelsR-134a refrigerant and special PAG lubricant
oil (never R-12)
Washer system All models4.8 US qt (4.5 l)MB Windshield Washer Concentrate2
2Use MB Windshield Washer Concentrate “MB SummerFit” and water for temperatures above freezing or MB Windshield Washer Concentrate “MB SummerFit” and
commercially available premixed washer solvent/antifreeze for temperatures below freezing point. Follow suggested mixing ratios (page 455).
Washer and headlamp cleaning*
systemAll models6.9 US qt (6.5 l)

452 Technical data
Fuels, coolants, lubricants etc.
Gasoline additives
A major concern among engine manufac-
turers is carbon build-up caused by gaso-
line. Mercedes-Benz recommends only the
use of quality gasoline containing additives
that prevent the build-up of carbon depos-
its.
After an extended period of using fuels
without such additives, carbon deposits
can build up especially on the intake valves
and in the combustion area, leading to
engine performance problems such as:

Warm-up hesitation

Unstable idle

Knocking/pinging

Misfire

Power lossIn areas where carbon deposits may be
encountered due to lack of availability of
gasolines which contain these additives,
Mercedes-Benz recommends the use of
additives approved by us for use on
Mercedes-Benz vehicles. Refer to Factory
Approved Service Products pamphlet (USA
only) or contact an authorized
Mercedes-Benz Center for a listing of ap-
proved product(s). Follow directions on
product label.
Do not blend other fuel additives with fuel.
This only results in unnecessary costs and
may be harmful to the engine operation.
Coolants
The engine coolant is a mixture of water
and anticorrosion/antifreeze, which pro-
vides:

Corrosion protection

Freeze protection

Boiling protection (by increasing the
boiling point)
The cooling system was filled at the factory
with a coolant providing freeze protection
to approximately -35°F (-37°C) and corro-
sion protection.
!Damage or malfunction resulting from poor
fuel quality or from blending additional fuel addi-
tives other than those tested and approved by us
for use on Mercedes-Benz vehicles listed in the
Factory Approved Service Products pamphlet
are not covered by the Mercedes-Benz Limited
Warranty.!Add premixed coolant solution only. Adding
water and MB 325.0 Anticorrosion/Antifreeze
separately from each other, could cause engine
damage not covered by the Mercedes-Benz Lim-
ited Warranty.

453 Technical data
Fuels, coolants, lubricants etc.
If the antifreeze mixture is effective to
-35°F (-37°C), the boiling point of the cool-
ant in the pressurized cooling system is
reached at approximately 266°F (130°C).
The coolant solution must be used year
round to provide the necessary corrosion
protection and increase boil-over protec-
tion. Refer to Maintenance Booklet for re-
placement interval.
Coolant system design and coolant used
determine the replacement interval. The
replacement interval published in the
Maintenance Booklet is only applicable if
MB 325.0 Anticorrosion/Antifreeze solu-
tion or other Mercedes-Benz approved
products of equal specification (see
Factory Approved Service Products pam-
phlet) are used to renew the coolant con-
centration or bring it back up to the proper
level.For information on other Mercedes-Benz
approved products of equal specification,
refer to the Factory Approved Service
Products pamphlet (USA only) or contact
an authorized Mercedes-Benz Center.
To provide important corrosion protection,
the solution must be at least 50% anticor-
rosion/antifreeze (equivalent to freeze
protection to approximately -35°F
[-37°C]). If you use a solution that is more
than 55% anticorrosion/antifreeze (freeze
protection to approximately -49°F
[-45°C]), the engine temperature will in-
crease due to the lower heat transfer capa-
bility of the solution. Therefore, do not use
more than this amount of anticorro-
sion/antifreeze.If the coolant level is low, water and
MB 325.0 Anticorrosion/Antifreeze
should be used to bring it up to the proper
level (have cooling system checked for
signs of leakage). Please make sure the
mixture is in accordance with label instruc-
tions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you
are not sure about the water quality, con-
sult an authorized Mercedes-Benz Center.