heating MERCEDES-BENZ R320 2008 W251 Owner's Manual

Contents
Safety and Security.......................... 69
Occupant safety................................... 70
Air bags .......................................... 72
Occupant Classification System ..... 77
Seat belts ....................................... 82
Active head restraints .................... 86
Rear head restraints ....................... 87
Children in the vehicle .................... 87
Blocking of rear door window
operation ........................................ 97
Panic alarm .......................................... 98
Activating ....................................... 98
Deactivating ................................... 98
Driving safety systems ......................... 99
ABS ................................................ 99
BAS .............................................. 101
ESP
®............................................. 101
EBP............................................... 105
Anti-theft systems.............................. 106
Immobilizer................................... 106
Anti-theft alarm system ................ 106
Controls in detail............................. 109
Locking and unlocking ....................... 110
SmartKey ..................................... 110
SmartKey with KEYLESS-GO* ...... 113
Checking the batteries in the
SmartKey or SmartKey with
KEYLESS-GO* .............................. 118
Loss of the SmartKey or
SmartKey with KEYLESS-GO* ...... 118
Opening the doors from the inside 118
Tailgate/Power tailgate*.............. 119
Automatic central locking ............ 126
Locking and unlocking from
the inside ..................................... 126
Seats ................................................. 128
Easy-entry/exit feature ................ 128
Lumbar support............................ 132
Multicontour seat* ....................... 132
Front seat active head restraints . 133
Rear seats .................................... 133
Seat heating* ............................... 139
Seat ventilation* (Canada only) ... 140Memory function* ............................. 141
Storing positions into memory ..... 142
Recalling positions from memory. 142
Lighting ............................................. 143
Exterior lamp switch .................... 143
Combination switch ..................... 147
Corner-illuminating front
fog lamps* ................................... 148
Hazard warning flasher ................ 150
Interior lighting ............................ 150
Door entry lamps ......................... 153
Cargo compartment lamp ............ 153
Instrument cluster ............................. 154
Adjusting instrument cluster
illumination .................................. 154
Resetting trip odometer ............... 155
Tachometer.................................. 155
Outside temperature indicator ..... 155

31 At a glance
Center console
Center console
Upper partItemPage
1COMAND system, see
separate operating
instructions
2Climate control208
3-zone automatic climate
control*222
Rear window defroster207
3Seat heating*,
front passenger side139
4Seat ventilation*,
front passenger side
(Canada only)140
5Vehicle level control
switch*279
6Program mode selector
switch for automatic
transmission200
ItemPage
7Front passenger front air
bag off indicator lamp 77,
425
8Hazard warning flasher
switch150
9Alarm system indicator
lamp107
aParktronic system*
deactivation switch284
bElectronic Stability Program
(ESP®) switch
104
cSeat ventilation*,
driver’s side (Canada only)140
dSeat heating*, driver’s side139
eAdaptive damping system
(ADS)* switch277

103 Safety and Security
Driving safety systems
For more information, see the “Practical
hints” section (
page 419) and
(
page 435).ETS/4-ETS (Electronic Traction System)
The Electronic Traction System is part of
the ESP
®.
The Electronic Traction System improves
the vehicle’s ability to utilize available trac-
tion, especially under slippery road condi-
tions. The brakes are applied to the
spinning wheel and power is transferred to
the wheel(s) with traction.
When you switch off the ESP
®, the
Electronic Traction System is still operat-
ing and will still apply the brake to a
spinning wheel.
For more information, see the “Practical
hints” section (
page 414) and
(
page 427).
!Vehicles with 4MATIC:
Because the ESP® operates automatically, the
engine and ignition must be shut off (SmartKey
in starter switch position0 or1 or KEYLESS-GO*
start/stop button in position0or1) when test-
ing the parking brake on a brake test dynamom-
eter and such testing should be no longer than
10 seconds.
Active braking action through the ESP
® may
otherwise seriously damage the brake system
which is not covered by the Mercedes-Benz
Limited Warranty.
iThe ESP® will only function properly if you
use wheels of the recommended tire size
(
page 529).
Warning!G
The Electronic Traction System cannot
prevent the natural laws of physics from act-
ing on the vehicle, nor can it increase the
traction afforded. The Electronic Traction
System cannot prevent accidents, including
those resulting from excessive speed in
turns, following another vehicle too closely,
or hydroplaning. Only a safe, attentive, and
skillful driver can prevent accidents.
The capabilities of an Electronic Traction
System equipped vehicle must never be
exploited in a reckless or dangerous manner
which could jeopardize the user’s safety or
the safety of others.
iIf the yellow ESP® warning lampv
comes on while driving, the Electronic Traction
System is being switched off temporarily to
prevent overheating of the drive wheel brakes.
In addition, the message
ESP Unavailable
See Operator’s Manual
appears in the
multifunction display.

139 Controls in detail
Seats
Seat heating*
The switches for front-seat heating are lo-
cated in the center console.
Front seat heating
1Seat heating switch
2Indicator lampsThe switches for the outboard second-row
seats are located in the rear center
console.
Outboard second-row seat heating
1Seat heating switch
2Indicator lampsThe red indicator lamps in the switch come
on to show which heating level you have
selected.
Switch on the ignition (page 39).
Level
3Three indicator lamps on
(highest level)
The seat heating automatically
switches to level 2 after approxi-
mately 5 minutes.
2Two indicator lamps on
The seat heating automatically
switches to level 1 after approxi-
mately 10 minutes.
1One indicator lamp on
(lowest level)
The seat heating automatically
switches off after approximately
20 minutes.
offNo indicator lamp on.

140 Controls in detail
Seats
Switching on
Press switch1.
Three red indicator lamps2 in the
switch come on.
Continue pressing switch1 until
desired seat heating level is reached.
Switching off
Press switch1 repeatedly until all
indicator lamps2 go out.
Seat ventilation* (Canada only)
Seat ventilation is available on the
R 550 4MATIC only.
The switches for the seat ventilation are
located in the center console.
1Seat ventilation switch
2Indicator lampsThe blue indicator lamps in the switch
come on to show which ventilation level
you have selected.
Switch on the ignition (page 39).
Switching on
Press switch1 repeatedly until the
desired ventilation level is set.
Switching off
Press switch1 repeatedly until all
indicator lamps2 go out.
iIf one or more of the indicator lamps2 on
seat heating switch 1 (
page 139) are flash-
ing, there is insufficient voltage due to too many
electrical consumers being switched on. The
seat heating switches off automatically.
The seat heating will switch back on again
automatically as soon as sufficient voltage is
available.
Level
3Three indicator lamps on
(highest level)
2Two indicator lamps on
1One indicator lamp on
(lowest level)
offNo indicator lamp on
iThe seat ventilation for the driver’s seat is
automatically set to the highest level if activated
via summer opening feature (
page 244).

215 Controls in detail
Climate control
The climate control switches to the follow-
ing functions automatically:

most efficient blower speed and
heating power, depending on outside
temperature

air flows onto the windshield and the
front door windows (side air vents must
be open)

the air conditioning compressor
switches on at outside temperatures
above approximately 41°F (5°C) for
air-dryingAdjustments
You can adjust the air volume and the tem-
perature when the front defroster is
switched on. The air flow will remain on the
windshield and front door windows.
Press button
to decrease or
buttonQ to increase air volume
(
page 210) to the desired level.
The air volume decreases/increases to
the next lower/higher blower speed
and heating switches to the tempera-
ture that was set before the front de-
froster was switched on.
The indicator lamp on button|
goes out. The indicator lamp on
button9 comes on.
or
Turn temperature
control1and/or7 (
page 210)
slightly in any direction.Heating switches to the temperature
that was set before the front defroster
was switched on.
The indicator lamp on button|
goes out. The indicator lamp on
button9 comes on.
iThe air conditioning compressor remains on
even if the indicator lamp in button| goes
out. This helps to prevent the windshield from
fogging.

216 Controls in detail
Climate control
Deactivating
Press button| (page 210) once
more.
The indicator lamp on the button goes
out. Defrosting is turned off.
The previous settings are in effect
again. The air conditioning compressor
remains switched on.
Windshield fogged on the outside
Switch the windshield wipers on
(
page 59).
Press button| (page 210).
The indicator lamp on the button
comes on.The climate control switches automatically
to the following functions:

most efficient blower speed and
heating power, depending on outside
temperature

air flows onto the windshield and the
front door windows (side air vents must
be open)

the air conditioning compressor
switches on at outside temperatures
above approximately 41°F (5°C) for
air-drying
If the automatic air distribution is switched
off:
Press air distribution button 9 or a
(
page 210).
Air recirculation mode
Switch to air recirculation mode to prevent
unpleasant odors from entering the vehicle
from the outside (e.g. before driving
through a tunnel). This setting cuts off the
intake of outside air and recirculates the
air in the passenger compartment.
iTo switch off, you can also press
button´ orU (
page 210).
iKeep this setting selected only until the
windshield is clear again.
Warning!G
Fogged windows impair visibility, endanger-
ing you and others. If the windows begin to
fog on the inside, switching off the air
recirculation mode immediately should clear
interior window fogging. If interior window
fogging persists, make sure the air
conditioning (
page 219) is activated, or
press button|.

219 Controls in detail
Climate control
Air conditioning
The air conditioning is operational while
the engine is running and cools the interior
air to the temperature set by the operator.
In addition, the air conditioning dehumidi-
fies the interior air at outside temperatures
above 41°F (5° C) and helps prevent
window fogging.
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 button9 (page 210).
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 button9 (page 210) 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
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.
Activating
Switch off the ignition (page 39).
Press button9 (page 210).
The indicator lamp on the button
comes on.
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 inte-
rior air is not dried. 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
off.
Have the air conditioning checked at the nearest
authorized Mercedes-Benz Light Truck Center.
iHow long the system will provide heating
depends on

the coolant temperature

the battery voltage
Regardless of the temperature and air volume
set on the climate control panel, an interior tem-
perature is aimed at by 72°F (22°C) and the
blower runs on low speed to protect the vehicle
battery.

220 Controls in detail
Climate control
Deactivating
Press button9 (page 210) again.
The indicator lamp on the button goes
out.
Rear climate control*
The control panel is located on the rear of
the front center console.
Rear climate control panel
Activating rear climate control
Press buttonU.
The indicator lamp on the button
comes on. The air volume and air distri-
bution are adjusted automatically.
iThe residual heat is automatically turned off:

when the ignition is switched on

after about 30 minutes

if the coolant temperature is too low

if the battery voltage drops
iThe rear climate control panel is only avail-
able if your vehicle is equipped with seat heating
for the second-row seats* or Rear Audio
feature* (see separate COMAND System operat-
ing instructions).
1Rear climate control on
(automatic mode)
2Air distribution (directs air through
the center air vents)
3Rear air conditioning off
4Air distribution (directs air through
the footwells and side air vents)
5Right rear center air vent, adjustable
6Left rear center air vent, adjustable
iThe climate control must be switched on
(
page 221).
iThe temperature is adjusted according to
the settings for the front passenger side made
on the front climate control panel (
page 213).

221 Controls in detail
Climate control
Deactivating rear climate control
Press button´.
The indicator lamp on the button goes
out.
The cooling function switches off after
a short delay.
Operating from the front
Deactivating
Press button: on the front climate
control panel (
page 210).
The indicator lamp on the button
comes on.Reactivating
Press button: on the front climate
control panel (
page 210).
The indicator lamp on the button goes
out. The rear climate control is
adjusted automatically.
Adjusting air distribution
Use the air distribution controls2 or4
to adjust the air distribution for the rear
passenger compartment.
The symbols on the controls represent the
following functions:Adjusting manually
Press the desired air distribution
control2 or4.
The indicator lamp on buttonU
goes out.
Adjusting automatically
Press buttonU.
The indicator lamp on the button
comes on. The air distribution is
adjusted automatically.
Adjusting air volume
The air volume for the rear zone corre-
sponds to the air volume settings for the
front passenger side. You can switch off
the air supply for the rear zone.
You can switch off the supplied amount of
air volume.
Press button´.
The indicator lamp on the button
comes on.
iSwitch off the rear climate control for
improved cooling or heating output in the front
passenger compartment.
You can also switch off the rear climate control
from the front passenger compartment
(
page 221).
SymbolFunction
ZDirects air to the center air
vents
YDirects air to the footwells and
the side air vents