coolant temperature MERCEDES-BENZ R320 2010 W251 Owner's Manual

Cargo net ...........................................
196
Cargo tie-down rings .........................188
Carpets, cleaning .............................. 267
Central locking
Automatic ................................ 74, 137
KEYLESS-GO
.................................... 71
Locking/unlocking from inside ........ 74
SmartKey ......................................... 70
Central locking/unlocking switch .....74
Certification label .............................. 344
Children in the vehicle
Air bags ........................................... 37
BabySmart™ air bag deactivation
system ............................................. 45
Child safety locks (rear doors) ......... 61
Child seat anchors – LATCH-type ....60
Indicator lamp, front passenger
front air bag off (Canada only) ......... 45
Indicator lamp, front passenger
front air bag off (USA only) .............. 42
Infant and child restraint systems .... 55
OCS (Occupant Classification
System) ........................................... 42
Override switch ................................ 62
Safety notes ..................................... 55
Tether anchorage points .................. 57
Top tether ........................................ 57
Child safety
see Children in the vehicle
Child seat anchors – LATCH-type
see Children in the vehicle
Chrome-plated exhaust tip,
cleaning .............................................. 268
Cigarette lighter ................................ 205
Climate control system ....................162
3-zone automatic climate control ..170
Air conditioning .....................167, 175
Air conditioning refrigerant ............ 352
Air distribution ....................... 168, 177
Air recirculation mode ........... 169, 179
Air volume ............................. 168, 178
Automatic mode .................... 167, 176
Climate control .............................. 164
Deactivating system ..............166, 175
Front defroster ...................... 168, 178
Residual heat and
ventilation .............................. 170, 180
Temperature .......................... 168, 176Clock
............................................ 28, 133
Cockpit ................................................. 27
Cold tire inflation pressure ..............249
Collapsible tire (spare wheel) ..........350
Collapsible wheel chock ...................272
COMAND system see separate COMAND system
operating instructions

Combination switch ..........................100
Comfort submenu Easy-entry/exit feature .................. 137
Fold-in function for exterior rear
view mirrors ................................... 138
Seat belt adjustment feature ......... 138
Compass
Calling up ....................................... 216
Control system .................................. 123
Multifunction display .....................125
Multifunction steering wheel ......... 123
Resetting to factory settings .......... 131
Control system menus ...................... 126
AIRMATIC/Compass ...................... 129
Audio/DVD .................................... 128
Distronic ........................................ 129
Navigation ..................................... 129
Settings ......................................... 130
Standard display ............................ 126
Telephone ...................................... 140
Trip computer ................................ 139
Vehicle status message memory ...130
Control system submenus
Comfort ......................................... 137
Instrument cluster .........................132
Lighting .......................................... 134
Time/Date ..................................... 133
Vehicle ........................................... 137
Coolant
Anticorrosion/antifreeze ............... 356
Capacities ...................................... 351
Checking level ............................... 225
Messages in the multifunction
display ........................................... 290
Corner-illuminating front fog
lamps .................................................. 101
Cruise control .................................... 142
Activating ....................................... 143
Canceling ....................................... 1436
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idle speed. If your foot is not firmly on the
brake pedal, the vehicle could accelerate
quickly forward or in reverse. You could lose
control of the vehicle and hit someone or
something. Only shift into gear when the
engine is idling normally and when your right
foot is firmly on the brake pedal.
! Only
shift the automatic transmission into
reverse gear R or park position P when the
vehicle is stopped. Otherwise the
automatic transmission could be damaged.
X Depress the brake pedal.
The gear selector lever can now be used.
X Shift the automatic transmission into drive
position D or reverse gear R.
i Shifting
the automatic transmission out of
park position P is only possible with the
brake pedal depressed.
Without the brake pedal depressed, the
gear selector lever can be moved up or
down. However, the parking pawl remains
engaged, not allowing shifting to occur.
X Wait for the gear selection process to
complete before setting the vehicle in
motion.
X If engaged, release the parking brake.
X Release the brake pedal.
X Carefully depress the accelerator pedal.
After a cold start, the automatic transmission
shifts at a higher engine speed. This allows
the catalytic converter (gasoline engine) or
the

oxidation catalyst (diesel engine) to reach
its operating temperature earlier.
For more information on driving, see “Driving
instructions” ( Y page 253). Problems while driving
The
engine runs erratically and misfires R
Gasoline engine: An ignition cable may be
damaged.
R The engine electronics may not be
operating properly.
R Gasoline engine: Unburned gasoline may
have entered the catalytic converter and
damaged it.
X Give very little gas.
X Have the problem checked at an authorized
Mercedes-Benz

Center as soon as possible.
The coolant temperature is above
248‡
(120†) The coolant is too hot and is no longer cooling
the engine.
X
Stop the vehicle in a safe location as soon
as possible.
X Turn off the engine immediately.
X Allow the engine and coolant to cool off.
X Check the coolant level and add coolant if
necessary ( Y page 225).
In case of accident If the vehicle is leaking fuel:
X
Do not start the engine under any
circumstances.
X Exit the vehicle at a safe distance from the
roadway.
X Notify local fire and/or police authorities.
If the extent of the damage cannot be
determined:
X Contact an authorized Mercedes-Benz
Center or call Roadside Assistance.
If no damage on major assemblies, fuel
system, and engine mount can be
determined:
X Start the engine in the usual manner. Driving and parking
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The following functions are available:
R
Restarting the tire pressure loss warning
system (Y page 232) (Canada only)
R Checking tire inflation pressure with the
Advanced TPMS (Y page 232) (USA only)
R Checking coolant temperature
(Y page 127)
R Calling up digital speedometer or outside
temperature ( Y page 127)
R Calling up maintenance service indicator
display ( Y page 262)
Checking coolant temperature G
Warning!
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.
X Press button & or * repeatedly until
the coolant temperature appears in the
multifunction display. During severe operating conditions, e.g. stop-
and-go traffic, the coolant temperature may
rise close to 248‡ (120†).
!
Excessive coolant temperature triggers a
warning in the multifunction display. The engine should not be operated with a
coolant temperature above 248‡
(120†). Doing so may cause serious
engine damage which is not covered by the
Mercedes-Benz Limited Warranty.
Calling up digital speedometer or
outside temperature You can select whether the digital
speedometer or the outside temperature
appears in the multifunction display
(Y page 133).
G
Warning!
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Indicated temperatures just above the
freezing point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges.
X Press button & or * repeatedly until
the digital speedometer or the outside
temperature appears in the multifunction
display. Digital speedometer
Outside temperature Control system
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i
The manually selected air recirculation
mode is deactivated automatically:
R after 5 minutes if the outside
temperature is below approximately
41‡ (5†)
R after 5 minutes if the air conditioning and
air-drying are turned off
R after 30 minutes if the outside
temperature is above approximately
41‡ (5†) Residual heat and ventilation
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.
i How long the system will provide heating
depends on the coolant temperature and
the battery voltage. Regardless of the temperature and air
volume set on the climate control panel, an
interior temperature is aimed at by 72‡
(22†) and the blower runs on low speed to
protect the vehicle battery.
X Activating: Switch off the ignition.
X Press button Á.
The indicator lamp in the button comes on.
X Deactivating: Press button Á again.
The indicator lamp in the button goes out.
The residual heat is deactivated automatically
R when the ignition is switched on
R after approximately 30 minutes
R if the battery voltage drops
R if the coolant temperature is too low 3-zone automatic climate control
Control panels
USA only170
3-zone automatic climate controlControls in detail
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i
The manually selected air recirculation
mode is deactivated automatically:
R after 5 minutes if the outside
temperature is below approximately
41‡ (5†)
R after
5 minutes if the air conditioning and
air-drying are turned off
R after 30 minutes if the outside
temperature is above approximately
41‡ (5†)
At outside temperatures above 79‡ (26†)
the system will not automatically switch back
to outside air. A quantity of outside air is
added after approximately 30 minutes. Residual heat and ventilation
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.
i How long the system will provide heating
depends on the coolant temperature and
the battery voltage.
Regardless of the temperature and air
volume set on the climate control panel, an
interior temperature is aimed at by 72‡
(22†) and the blower runs on low speed to
protect the vehicle battery.
X Activating: Switch off the ignition.
X Press button Á.
The
indicator lamp in the button comes on.
X Deactivating: Press button Á again.
The indicator lamp in the button goes out.
The residual heat is deactivated
automatically:
R when the ignition is switched on
R after approximately 30 minutes
R if the battery voltage drops
R if the coolant temperature is too low Using driver-side settings for all
temperature zones
This feature is only available in Canada
vehicles.
You can use the settings of the driver’s side,
such as temperature, air volume and air
distribution,

for all temperature zones. These
settings only need to be made once and the
climate control system will automatically
regulate the settings for all temperature
zones quickly and comfortably.
X Activating:
Adjust the air temperature, air
volume and air distribution.
X Press button ¸.
The
indicator lamp in the button comes on.
The driver-side settings are used for all
temperature zones.
X Deactivating: Press button ¸ again.
The indicator lamp in the button goes out.
i If you manually set the temperature, air
volume

or air distribution for the passenger
side or the rear passenger compartment
when the MONO setting is active, the
MONO setting will be switched off. Rear window defroster
G
Warning!
Any accumulation of snow and ice should be
removed
from the rear window before driving.
Visibility could otherwise be impaired,
endangering you and others.
The rear window defroster uses a large
amount of power. To keep the battery drain
to a minimum, switch off the defroster as
soon as the rear window is clear. The
defroster is switched off automatically after
some time of operation depending on the
outside temperature. 180
Rear window defroster
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i
Leaving the engine running and the fuel
filler cap open can cause the yellow fuel
tank
reserve warning lamp to flash and the
malfunction indicator lamp ! (USA
only) or ; (Canada only) to illuminate.
For more information, see also “Practical
hints” (Y page 305).
X Remove the SmartKey from the starter
switch.
KEYLESS-GO: Open the driver’s door (this
puts the starter switch in position 0, same
as with the SmartKey removed from the
starter switch). The driver’s door then can
be closed again.
X Opening: Press fuel filler flap : at the
point indicated by the arrow.
X Turn fuel filler cap ; counterclockwise.
X Take off fuel filler cap ;.
! The fuel filler cap is tethered to the fuel
filler neck. Do not drop the cap. It could
damage the vehicle paint finish.
X Set fuel filler cap ; on fuel filler flap :.
X Fully insert filler nozzle unit and refuel.
X Only fill your tank until the filler nozzle unit
cuts out – do not top off or overfill .
X Closing: Turn fuel filler cap ; clockwise
until it audibly engages.
X Close fuel filler flap :.
Low outside temperatures (diesel
engine) !
Do not fill the tank with gasoline. Do not
blend

diesel fuel with gasoline or kerosene.
The fuel system and engine will otherwise
be damaged, which is not covered by the
Mercedes-Benz Limited Warranty.
To prevent malfunctions, diesel fuel with
improved cold flow characteristics is offered
in the winter months. Check with your fuel
retailer. Check regularly and before a long trip
For information on quantities and
requirements

of operating agents, see “Fuels,
coolants, lubricants, etc.” (Y page 350).
Check the following:
R Engine oil level ( Y page 224)
R Tire inflation pressure ( Y page 230)
R Coolant level ( Y page 225)
R Vehicle lighting ( Y page 313)
R Washer system and headlamp cleaning
system (Y page 226)
R Brake fluid ( Y page 227) Engine compartment
Hood
G
Warning!
Do not pull the release lever while the vehicle
is in motion. Otherwise the hood could be
forced open by passing air flow.
This

could cause the hood to come loose and
injure you and/or others.
Opening G
Warning!
Do not open the hood when the engine is
overheated. You could be seriously injured.
Observe the coolant temperature display to
determine whether the engine may be
overheated. If you see flames or smoke
coming from the engine compartment, move
away from the vehicle. Wait until the engine
has cooled. If necessary, call the fire
department. G
Warning!
You could be injured when the hood is open –
even when the engine is turned off.
Parts of the engine can become very hot. To
prevent

burns, let the engine cool completely
before touching any components on the 222
Engine compartment
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For more information on engine oil, see
“Fuels, coolants, lubricants etc.”
(Y page 350).
For information on messages in the
multifunction display concerning engine oil,
see the “Practical hints” section
(Y page 293).
Adding engine oil
!
Only use approved engine oils and oil
filters required for vehicles with
Maintenance System. For a listing of
approved engine oils and oil filters, contact
an authorized Mercedes-Benz Center or
visit www.mbusa.com (USA only).
The following will result in engine or
emission control system damage not
covered by the Mercedes-Benz Limited
Warranty:
R Using engine oils and oil filters of
specification other than those expressly
required for the Maintenance System.
R Changing of oil and oil filter at change
intervals longer than those called for by
the Maintenance System.
R Using any oil additives. Example illustration: R 350
X
Unscrew filler cap : from filler neck.
X Add engine oil as required. Be careful not
to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water. !
Excess oil must be siphoned or drained
off. It could cause damage to the engine
and emission control system not covered
by the Mercedes-Benz Limited Warranty.
X Screw filler cap : back on filler neck.
For more information on engine oil, see the
“Technical data” section ( Y page 350) and
(Y page 352). Transmission fluid level
The transmission fluid level does not need to
be checked. If you notice transmission fluid
loss or gearshifting malfunctions, have an
authorized Mercedes-Benz Center check the
transmission. 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, and the
coolant temperature must be below 158‡
(70†). G
Warning!
In order to avoid any potentially serious burns:
R 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 display indicates
that the coolant is overheated.
R Do not remove the cap on the coolant
expansion tank if the coolant temperature
is above 158‡ (70†). Allow the engine to
cool down before removing the cap. The
coolant expansion tank contains hot fluid
and is under pressure.
R Using a rag, slowly open the cap
approximately 1
/ 2 turn to relieve excess
pressure. If opened immediately, scalding Engine compartment
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hot fluid and steam will be blown out under
pressure.
R Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. X
Using a rag, slowly open cap ;
approximately 1
/ 2 turn to relieve excess
pressure.
X Continue turning cap ; counterclockwise
and remove it.
The coolant level is correct if the level
R for cold coolant: reaches marking
bar : in coolant expansion tank =
R for warm coolant: is approximately 0.6 in
(1.5 cm) higher
X Add coolant as required.
X Screw cap ; back on and tighten it.
For more information on coolant, see the
“Technical data” section ( Y page 351) and
(Y page 355). Washer system and headlamp
cleaning system
G
Warning!
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned. !
Always use washer solvent/antifreeze
where temperatures may fall below
freezing point. Failure to do so could result
in damage to the washer system/fluid
reservoir.
! Only use washer fluid which is suitable for
plastic lenses. Improper washer fluid can
damage the plastic lenses of the
headlamps.
! Do not use distilled or deionized water in
the washer fluid reservoir. Otherwise, the
washer fluid level sensor could be
damaged. Fluid for the washer system, rear window
washer system, and the headlamp cleaning
system is supplied from washer fluid
reservoir ;.
During all seasons, use MB Windshield
Washer Concentrate “MB SummerFit”. Mix it
with water or premixed washer solvent/
antifreeze depending on the ambient
temperature (
Y page 357).
X Opening washer fluid reservoir: Pull tab
of cap : upwards.
X Refill the washer fluid reservoir.
X Closing washer fluid reservoir: Press
cap : onto filler hole until it engages.
For more information, see “Washer system
and headlamp cleaning system”
(Y page 351). 226
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Do not attempt to straighten out the tow
vehicle
and trailer by increasing the speed.
R If the transmission shifts between gears on
inclines repeatedly, shift to a lower gear
range manually ( Y page 119). Select 4, 3,
2 or 1.
A lower gear and reduction of speed
reduces the chance of engine overloading
and/or overheating.
R When going down an incline, shift into a
lower gear and use the engine’s braking
effect.
Avoid riding the brakes, thus overheating
the vehicle and trailer brakes (if so
equipped).
R If the engine coolant rises to an extremely
high temperature when the air conditioning
is on, turn off the air conditioning system.
Engine coolant heat can be additionally
vented by opening the windows, switching
the climate control fan speed to high and
setting the temperature control to the
maximum.
R During a passing maneuver extreme care
must be exercised since your vehicle with
a trailer will require additional passing
distance ahead than when driving without
a trailer.
Because your vehicle and trailer is longer
than your vehicle alone, you will also need
to go much farther ahead of the passed
vehicle before you can return to your lane.
Decoupling a trailer G
Warning!
Vehicles with AIRMATIC: While you are
coupling or decoupling a trailer, make sure
nobody locks or unlocks the vehicle and/or
opens or closes doors or the tailgate.
The vehicle’s level could change and you
could endanger yourself and/or others as a
result. Make sure that you do not operate the ADS
switch or the vehicle level control system
when coupling/decoupling the trailer.
X Make sure the automatic transmission is in
park position P (Y page 116).
X Engage the parking brake for the vehicle
(Y page 114).
X Start the engine (Y page 110).
X Close all doors and the tailgate.
X Engage the parking brake for the trailer. G
Warning!
Vehicles with AIRMATIC: As soon as you
disconnect
the electrical connection between
the trailer and the vehicle, the vehicle will
lower. To help avoid personal injury, make
sure no one is near the wheel housing or
underneath the vehicle before the electrical
connection is disconnected.
When you decouple the trailer, the vehicle is
temporarily raised because the springs are
relieved of load. Be especially careful during
this process, as you could otherwise injure
yourself and/or others. Make sure that any
persons remaining in the vehicle do not press
the switches for vehicle level control or the
ADS.
X Disconnect all electrical plug connectors.
X Decouple the trailer.
X Make sure that the trailer coupling is free
of load.
X Turn off the engine ( Y page 114). Driving abroad
If
you plan to drive the vehicle outside the U.S.
or Canada, you should request dealer
network information for your destination from
any authorized Mercedes-Benz Center. Driving instructions
259
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Display messages
Possible causes/consequences and
X Solutions? Coolant
Stop car,
switch
engine
off. The coolant is too hot.
X
Stop the vehicle immediately as soon as it is safe to do so.
X Turn off the engine immediately.
X Engage the parking brake.
X Only start the engine again after the message disappears.
You could otherwise damage the engine.
X Observe the coolant temperature in the multifunction
display.
X If the temperature rises again: Contact an authorized
Mercedes-Benz Center immediately.
During severe operation conditions and stop-and-go city
traffic, the coolant temperature may rise close to 248‡
(120†). G
Warning!
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‡ (120†).
Doing so may cause serious damage which is not covered by the Mercedes-Benz Limited
Warranty. Vehicle status messages in the multifunction display
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