2002 MERCEDES-BENZ ML55AMG cooling

111 Automatic climate control
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Automatic climate control
The automatic climate control only operates with the
engine running.
The system is always at operational readiness, except
when manually switched off.
In the automatic mode the automatic climate control
cools or heats the interior depending on outside
temperature and the selected interior temperature.
Make the temperature settings in small increments.
If the vehicle interior has been heated by direct sunlight
and is very hot, ventilate the interior (open door or
windows for a short period) before driving off
Keep the air intake grill in front of the windshield free
of debris and snow.
The air conditioning mode removes considerable
moisture from the air during operation in the cooling
mode. It is normal for water to drip on the ground
through ducts in the underbody.
If the economy mode AC
OFF
is selected, the air
conditioning compressor will not engage and it is not
possible to air condition in this setting. See page 117.Notes:
The interior temperature sensor (10) should not be
touched to maintain a precise temperature.
If the vehicle travels from shade into direct sunlight, a
sensor automatically increases the air volume
temporarily to maintain the interior temperature.
The automatic climate control will not remove moisture
from the air at low outside ambient temperatures.
The air conditioner switches itself off for its own
protection if refrigerant is lost. No cooling will then take
place. Economy mode AC
OFF
cannot be switched off.
Have the air conditioner checked by a Mercedes-Benz
Center should this happen.
Dustfilter
Nearly all dust particles and pollen are filtered out
before outside air enters the passenger compartment
through the air distribution system.
Severe conditions (e.g. strong air pollution) may require
replacement of the filter before its scheduled interval.
A clogged filter will reduce the air volume to the
interior.

116 Automatic climate control
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Air recirculation
This mode can be selected to temporarily reduce the
entry of annoying odors or dust into the vehicle’s
interior.
Outside air is not supplied to the vehicles’s interior.
To select, press briefly O button. The indicator lamp
in button lights up.
To cancel, press briefly O button again. The indicator
lamp in button goes out.
The system automatically switches from air
recirculation to fresh air, after:
•approx. 30 minutes, when the automatic climate
control switched on,
•approx. 5 minutes, when the automatic climate
control switched off.
•approx. 5 minutes, if the outside temperature is
below 45˚F (7˚C).
If the windows should fog up from the inside, switch
from recirculated air back to fresh air.Note:
To achieve the fastest possible cooling of the interior, the
automatic climate control automatically switches to air
recirculation.
The indicator lamp in the Obutton is not illuminated
when the system automatically switches to air
recirculation.

118 Automatic climate control
Te ch n i c a l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Switching the automatic climate control on and off
To s witch of f:
Set air volume control wheel to position0.
The indicator lamp in the Ubutton goes out.
The fresh air supply to the vehicle interior is shut off.
While driving, use this setting only temporarily,
otherwise the windshield could fog up.
To s witch on:
Press the Ubutton. The indicator lamp in the button
illuminates.Switching off the rear passenger compartment
ventilation and rear passenger climate control
For an improved cooling or heating output in the front
passenger compartment, the rear passenger
compartment ventilation can be switched off.
To s w i tch o f f :
Press the REAR-OFF button, see page 110. The indicator
lamp in the button illuminates.
The operation of the rear automatic climate control in
the center console and the fresh air supply to the rear
compartment is shut off.
To a c t i va t e :
Press REAR-OFF button again. The indicator lamp in the
button goes out.
The rear automatic climate control in the center console
switches to automatic mode and fresh air enters the rear
compartment.
For notes on the rear passenger compartment climate
control, see page 119.

246 Malfunction and indicator lamps
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
Low engine oil level warning lamp
With the key in steering lock position 2, the
oil level warning lamp comes on and should
go out when the engine is running.
If the warning lamp does not go out after starting the
engine, or comes on with the engine running and at
operating temperature, the engine oil level has dropped
to approximately the minimum mark on the dipstick.
When this occurs, the warning lamp will first come on
intermittently and then stay on if the oil level drops
further.
If no oil leaks are noted, continue to drive to the nearest
service station where the engine oil should be topped to
the “full” mark on the dipstick with an approved oil.
The low engine oil level warning light should not be
ignored. Extended driving with the light illuminated
could result in serious engine damage that is not
covered by the Mercedes-Benz Limited Warranty.
In addition to the warning lamp, the engine oil level
should be periodically checked with the dipstick or via
the oil level indicator in the odometer display field, for
example during a fuel stop, or before a long trip (see
engine oil level indicator on page 96 and checking
engine oil on page 255).Low engine coolant level warning
When the coolant level warning lamp comes
on while driving, then the coolant level has
dropped below the required level, or the
coolant temperature is in the red zone. If no leaks are
noticeable and the engine temperature does not
increase, continue to drive to the nearest service station
and have coolant added to the coolant system, see
page 256. If the engine temperature reaches the red
zone, move vehicle to an area which is in a safe distance
from the roadway and turn off the engine. Also see
coolant temperature gauge on page 87.
The low engine coolant level warning should not be
ignored. Extended driving with the symbol displayed
may cause serious engine damage not covered by the
Mercedes-Benz Limited Warranty.
In cases of major or frequent minor coolant loss, have
the cooling system checked at your authorized
Mercedes-Benz Light Truck Center as soon as possible.
Notes:
Do not drive without coolant in the cooling system. The
engine will overheat causing major engine damage.
Monitor the coolant temperature gauge while driving.

257 Engine compartment
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index Adding coolant
If coolant has to be added, a 50 / 50 mixture of water and
MB anticorrosion / antifreeze should be added.
After adding coolant, close cap until you hear it click a
few times.
The drain plugs for the cooling system are located on
the left and right side of the engine block directly above
the engine mounts and at the bottom of the radiator.
Anticorrosion / antifreeze mixture, see page 319.
Wa r n i n g !
In order to avoid possible serious burns or injury:
• 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 indicates 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 cap approximately
1/2 turn to relieve excess pressure. 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 glycol which may
burn if it comes into contact with hot engine
parts.

315 Fuels, coolants, lubricants etc. - capacities
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index Brake system
(MB Brake fluid [DOT 4+])approx. 0.75 US qt (0.7 l)
Windshield / headlamp washer system
(MB Windshield washer concentrate “S”
1)approx. 8.0 US qt (7.6 l)
Cooling system
(MB Anticorrosion / antifreeze)approx. 12.7 US qt (12.0 l)
Fuel tank
including a reserve of
(Premium unleaded gasoline:
Posted Octane 91 (Avg. of 96 RON / 86 MON))ML320 / ML 500
ML 55 AMGapprox. 22.0 US gal (83.0 l)
approx. 3.2 US gal (12.0 l)
approx. 25.0 US gal (95.0 l)
approx. 3.2 US gal (12.0 l)
Air conditioner system
(R-134a refrigerant and special
PA C l u b r i c a n t (Never R-12))
1 Use MB Windshield Washer Concentrate “S” and water for temperatures above freezing or MB Windshield Washer Concentrate “S” and
commercially available premixed windshield washer solvent / antifreeze for temperatures below freezing. Follow suggested mixing ratios, see
page 259.Fuels, coolants, lubricants etc. Model Capacity

318 Fuels, coolants, lubricants etc.
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
Gasoline additives
A major concern among engine manufacturers is carbon
build up caused by gasoline. Mercedes-Benz
recommends the use of only quality gasoline containing
additives that prevent the build up of carbon deposits.
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 loss.
Do not blend other specific fuel additives with fuel.
They only result in unnecessary cost, and may be
harmful to the engine operation.
Damage or malfunctions resulting from poor fuel
quality or from blending specific fuel additives are not
covered by the Mercedes-Benz Limited Warranty.Coolants
The engine coolant is a mixture of water and
anticorrosion / antifreeze, which provides:
•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 corrosion protection.
If the antifreeze mixture is effective to -22
°F (-30
°C), the
boiling point of the coolant in the pressurized cooling
system is reached at approx. 266
°F (130
°C).
The coolant solution must be used year round to provide
the necessary corrosion protection and increase in the
boil-over protection. You should have it replaced every
3years.
To provide the important corrosion protection, the
solution must be at least 45% anticorrosion / antifreeze
(equals a freeze protection to approx. - 22°F [-30
°C]). If
you use a solution that is more than 55% anticorrosion/
antifreeze (freeze protection to approx. - 49
°F [-45
°C])-,

319 Fuels, coolants, lubricants etc.
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index the engine temperature will increase due to the lower
heat transfer capability of the solution. Therefore, do not
use more than this amount of anticorrosion / antifreeze.
If the coolant level is low, water and MB anticorrosion/
antifreeze should be used to bring it up to the proper
level (have cooling system checked for signs of leakage).
The water in the cooling system must meet minimum
requirements, which are usually satisfied by normal
drinking water. If your are not sure about the water
quality, consult your authorized Mercedes-Benz Light
Truck Center.
Anticorrosion/antifreeze
Your vehicle contains a number of aluminum parts. The
use of aluminum components in motor vehicle engines
necessitates that anticorrosion / antifreeze coolant used
in such engines be specifically formulated to protect the
aluminum parts. (Failure to use such anticorrosion/
antifreeze coolant will result in a significantly
shortened service life.)
Therefore the following product is strongly
recommended for use in your vehicle: Mercedes-Benz
Anticorrosion / antifreeze agent.Before the start of the winter season (or once a year in
the hot southern regions), you should have the
anticorrosion / antifreeze concentration checked. The
coolant is also regularly checked each time you bring
your vehicle to your authorized Mercedes-Benz Light
Truck Center for service.
Anticorrosion / antifreeze quantity
Approx. freeze protection
– 35
°F
(– 37°C)– 49
°F
(– 45°C)
6.4 US qt
(6.0 l)7. 0 U S q t
(6.6 l)