MERCEDES-BENZ R320 2010 W251 Repair Manual

G
Warning!
After installing top tether straps, make sure
the seats are locked properly, the seat
backrests are in an upright position and they
are locked properly.
An outboard second-row seat is locked
properly only when the lock status indicator
is in hinged position and the red marking is
barely visible.
If a seat and seat backrest are not locked
properly, the seat could move forward and the
seat backrest could fold. The child seat would
no longer be supported properly or positioned
to provide its intended benefit. That could
cause serious or even fatal injuries.
X Lower the head restraint if necessary
(Y page 88).
Make sure top tether strap ? can pass
freely between the head restraint and top
of the seat backrest.
X Install the child restraint system and
tighten top tether strap ? according to the
child restraint manufacturer’s instructions.
After removing the child restraint system and
top tether strap ?:
X Reinstall anchorage ring cover :.
Second-row middle seat G
Warning!
Only install a child seat in the second-row
middle seat position if the outboard seat belt
buckle is not obstructed or overlapped by the
child seat. Not all child seats, including some
Mercedes-Benz approved child seats, can be
used in this seating position. Contact an
authorized Mercedes-Benz Center for more
information.
Do not use the LATCH anchors or seat belt
buckle for the outboard seats in conjunction
with a child seat in the second-row middle
seat position. Child seats in the middle
seating position must only be secured by the
middle seat position seat belt inserted into the seat belt buckle for the second-row
middle seat.
G
Warning!
Please be aware that installation of a child
seat in the second-row middle seat position
can prevent the folding forward of the
outboard second-row seats which can
obstruct access to and exit from the third-row
seats. In case of an accident it will be difficult
for occupants of the third-row seats to leave
the vehicle. Serious injuries could result.
Install a child seat in one of the outboard
seating positions according to the installation
instructions if access to the third-row seats is
required.
X Move the head restraint to its uppermost
position (Y page 88). X
Pull seat backrest release strap : in the
direction of arrow. Occupant safety
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X
Fold seat backrest ; forward to seat
cushion = as far as necessary for you to
access anchorage ring ?. X
Guide top tether strap B between head
restraint and top of the seat backrest.
X Securely fasten hook A, which is part of
top tether strap B, to anchorage ring ?.
Make sure
R top tether strap B is not twisted
R the head restraint is installed and
positioned such that top tether strap B
can pass freely between the head restraint
and top of the seat backrest
R top tether strap B is positioned between
the seat backrest and the cargo
compartment cover blind (if installed)
R top tether strap B is positioned between
the seat backrest and the cargo net (if
installed)
i For safety, make sure hook A is attached
to anchorage ring ? beyond the safety
catch, as illustrated.
X Fold seat backrest up and push backwards
until it engages audibly. G
Warning!
After installing the top tether strap, make sure
the seat backrest is in an upright position and
is locked properly.
If the seat backrest is not locked properly, the
seat backrest could fold. The child seat would no longer be supported properly or positioned
to provide its intended benefit. That could
cause serious or even fatal injuries.
X Lower the head restraint if necessary
(Y page 88).
Make sure top tether strap B can pass
freely between the head restraint and top
of the seat backrest.
X Install the child restraint system and
tighten top tether strap B according to the
child restraint manufacturer’s instructions.
Child seat anchors – LATCH-type G
Observe Safety notes, see page 55. G
Warning!
Children too big for a toddler restraint must
ride in seats using regular seat belts. Position
shoulder belt across chest and shoulder, not
face or neck.
A booster seat may be necessary to achieve
proper seat belt positioning for children over
41 lb (18 kg) until they reach a height where
a lap/shoulder belt fits properly without a
booster.
Install child seat according to manufacturer’s
instructions.
The child seat must be firmly attached to both
anchors.
An incorrectly mounted child seat may come
loose during an accident which could result in
serious injury or death to the child.
Damaged or impact damaged child seats or
child seat mounting fittings must be replaced.
Each of the outboard second-row seats and
third-row seats has two LATCH-type anchors
for the installation of a LATCH-type child seat
with matching mounting fittings.
Non-LATCH-type child seats may also be used
and can be installed using the vehicle’s seat
belt system. Install child seat according to the
manufacturer’s instructions. 60
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The LATCH-type anchors on the outboard
second-row seats are covered with
upholstery blends.
Information sign
; indicates the position of
anchor :.
X Move the respective outboard second-row
seat backrest to an upright position
(Y page 87).
X Push the upholstery blend to the side.
X Install a LATCH-type child seat according
to the manufacturer’s instructions.
A rigid connection between the child seat
and the body of the vehicle is established.
The LATCH-type anchors on the third-row
seats are blended with covers. X
Remove anchorage ring covers = from
anchors ? of the third-row seat on which
a child seat is to be installed.
X Install a LATCH-type child seat according
to the manufacturer’s instructions.
A rigid connection between the child seat
and the body of the vehicle is established.
Child safety Child safety locks
G
Observe Safety notes, see page 55. G
Warning!
Children could open a rear door from the
inside. This may cause serious personal injury
or an accident. Therefore, secure the rear
doors with the child safety locks whenever
children are riding in the back seats of the
vehicle.
The child safety locks on the rear doors
enable you to secure each rear door
individually. You cannot open a secured rear
door from the inside. You can open the rear
door from the outside when the vehicle is
unlocked. Occupant safety
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X
Securing: Press the lever down in direction
of arrow ;.
X Check to make sure the child safety locks
are working properly.
X Releasing: Press the lever up in direction
of arrow :.
Override switch G
Observe Safety notes, see page 55.
With the override switch you can disable the
rear door window switches in the rear door
panels. This can be useful, for instance, when
you have children riding in the rear passenger
compartment. G
Warning!
Activate the override switch when children
are riding in the back seats of the vehicle. The
children may otherwise injure themselves,
e.g. by becoming trapped in the rear door
window opening. X
Activating: Press override switch :.
The switch engages in recessed position. The rear door windows can no longer be
operated using the respective switch
located in the rear doors.
You can still operate the rear door windows
using the switches located on the door
control panel of the driver’s door.
X Deactivating: Press override switch :
again.
The switch disengages from its recessed
position back to its original position.
The rear door windows can be operated
again using the respective switch located
in the rear doors.
For more information on power windows, see
the “Controls in detail” section
(Y page 106). Panic alarm
Example illustration: SmartKey with KEYLESS-GO
X
Activating: Press and hold !
button : for at least 1 second.
An audible alarm and flashing exterior
lamps will operate briefly.
X Deactivating: Press ! button : again.
or
X Insert the SmartKey into the starter switch.
or
X Press the KEYLESS-GO start/stop button.
The SmartKey with KEYLESS-GO must be
inside the vehicle. 62
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i
USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1.
This device may not cause harmfulinterference, and
2. this device must accept any interference received, including
interference that may cause undesired
operation.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment.
i Canada only:
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause interference, and
2. this device must accept any interference received, including
interference that may cause undesired
operation of the device.
Any unauthorized modification to this
device could void the user’s authority to
operate the equipment. Driving safety systems
Introduction
This section contains information about the
following driving safety systems:
R ABS ( Antilock Brake System)
R BAS ( Brake Assist System)
R EBP ( Electronic Brake Proportioning)
R ESP ®
( Electronic Stability Program)
i In winter operation, the maximum
effectiveness of most of the driving
systems described in this section is only achieved with winter tires, or snow chains
as required.
Safety notes G
Warning!
The following factors increase the risk of
accidents:
R Excessive speed, especially in turns
R Wet and slippery road surfaces
R Following another vehicle too closely
The driving safety systems described in this
section cannot reduce these risks or prevent
the

natural laws of physics from acting on the
vehicle. They cannot increase braking or
steering efficiency beyond that afforded by
the condition of the vehicle brakes and tires
or the traction afforded.
Only a safe, attentive, and skillful driver can
prevent accidents.
The capabilities of a vehicle equipped with the
driving safety systems described in this
section must never be exploited in a reckless
or dangerous manner which could jeopardize
the user’s safety or the safety of others.
Always adjust your driving style to the
prevailing road and weather conditions and
keep a safe distance to other road users and
objects on the street.
If a driving system malfunctions, other driving
safety systems may also switch off. Observe
indicator and warning lamps that may come
on as well as messages in the multifunction
display that may appear. ABS
G
Observe Safety notes, see page 63. G
Warning!
Do not pump the brake pedal. Use firm, steady
brake pedal pressure instead. Pumping the
brake pedal defeats the purpose of the ABS Driving safety systems
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and significantly reduces braking
effectiveness.
The Antilock Brake System (ABS) regulates
the
brake pressure so that the wheels do not
lock during braking. This allows you to
maintain the ability to steer your vehicle.
The ABS is functional above a speed of
approximately 5 mph (8 km/h) independent
of road surface conditions.
On slippery road surfaces, the ABS will
respond even to light brake pressure.
The ABS indicator lamp ! indicator lamp
in the instrument cluster comes on when you
switch on the ignition. It goes out when the
engine is running.
Braking At the instant one of the wheels is about to
lock up, a slight pulsation can be felt in the
brake pedal. The pulsation indicates that the
ABS is in the regulating mode.
X
Keep firm and steady pressure on the brake
pedal while you feel the pulsation.
Continuous, steady brake pedal pressure
yields the advantages provided by the ABS,
namely

braking power and the ability to steer
the vehicle.
The pulsating brake pedal can be an
indication of hazardous road conditions and
functions as a reminder to take extra care
while driving.
Emergency brake maneuver X
Keep continuous full pressure on the brake
pedal. G
Warning!
If the ABS malfunctions, other driving safety
systems
such as the BAS or the ESP ®
are also
switched off. Observe indicator and warning
lamps that may come on as well as messages
in the multifunction display that may appear. If the ABS malfunctions, the wheels may lock
during hard braking, reducing steering
capability

and extending the braking distance. BAS
G
Observe Safety notes, see page 63.
The Brake Assist System (BAS) operates in
emergency
situations. If you apply the brakes
very quickly, the BAS provides full brake
boost automatically, thereby potentially
reducing the braking distance.
X Apply continuous full braking pressure until
the emergency braking situation is over.
The ABS will prevent the wheels from
locking.
When you release the brake pedal, the brakes
function again as normal. The BAS is then
deactivated. G
Warning!
If the BAS malfunctions, the brake system still
functions, but without the additional brake
boost available that the BAS would normally
provide in an emergency braking maneuver.
Therefore,

the braking distance may increase. EBP
G
Observe Safety notes, see page 63.
The Electronic Brake Proportioning (EBP)
enhances braking effectiveness by allowing
the

rear brakes to supply a greater proportion
of the braking effort in straight-line braking
without a loss of vehicle stability. G
Warning!
If the EBP malfunctions, the brake system will
still function with full brake boost. However,
the rear wheels could lock up during
emergency braking situations, for example.
You could lose control of the vehicle and
cause an accident.
Adapt your driving style to the changed
driving characteristics. 64
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ESP
® G
Observe Safety notes, see page 63.
The Electronic Stability Program (ESP ®
) is
operational as soon as the engine is running.
It monitors the vehicle’s traction (force of
adhesive friction between the tires and the
road surface) and handling.
The ESP ®
recognizes that the vehicle deviates
from the direction of travel as intended by the
driver. By applying brakes to individual
wheels and by limiting the engine output, the
ESP ®
works to stabilize the vehicle. The
ESP ®
is especially useful while driving off and
on wet or slippery road surfaces. The ESP ®
also stabilizes the vehicle during braking and
steering maneuvers.
The ESP ®
warning lamp d in the
instrument cluster comes on when you switch
on the ignition. It goes out when the engine
is running.
The ESP ®
warning lamp d in the
instrument cluster flashes when the ESP ®
is
engaged. G
Warning!
Never switch off the ESP ®
when you see the
ESP ®
warning lamp d flashing in the
instrument cluster. In this case proceed as
follows:
R When driving off, apply as little throttle as
possible.
R While driving, ease up on the accelerator
pedal.
R Adapt your speed and driving style to the
prevailing road conditions.
Failure to observe these guidelines could
cause the vehicle to skid. The ESP ®
cannot
prevent accidents resulting from excessive
speed.
! Only

conduct operational or performance
tests on a two-axle dynamometer. If such
tests are necessary, contact an authorized Mercedes-Benz Center. You could
otherwise seriously damage the brake
system or the transfer case which is not
covered by the Mercedes-Benz Limited
Warranty.
! Because the ESP ®
operates
automatically,

the engine and ignition must
be shut off (SmartKey in starter switch
position 0 or 1 or KEYLESS-GO start/stop
button in position 0 or 1) when the parking
brake is being tested on a brake test
dynamometer. 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.
! The ESP ®
will only function properly if you
use wheels of the recommended tire size
as specified in the “Technical data” section
of this Operator’s Manual.
i The Distronic system and cruise control
switch off automatically when the ESP ®
engages.
Electronic Traction System (4-ETS) G
Observe Safety notes, see page 63.
The 4-ETS (four-wheel Electronic Traction
System) is a component of the ESP ®
. The
4-ETS

improves the vehicle’s ability to utilize
available traction, especially under slippery
road conditions by applying the brakes to a
spinning wheel. In addition, more power is
transferred to the wheel(s) with traction.
When you switch off the ESP ®
, the 4-ETS is
still enabled.
Switching off the ESP ® G
Warning!
The ESP ®
should not be switched off during
normal driving other than in the Driving safety systems
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circumstances described below. Disabling
the system will reduce vehicle stability in
driving maneuvers.
Do not switch off the ESP
®
when a spare
wheel is mounted.
To improve the vehicle’s traction, switch off
the ESP ®
. This allows the drive wheels to spin
and thus cut into surfaces for better grip, for
example
R when driving with snow chains
R in deep snow
R in sand or gravel G
Warning!
Switch on the ESP ®
immediately if the
aforementioned circumstances do not apply
anymore. Otherwise the ESP ®
will not
stabilize the vehicle when it is starting to skid
or a wheel is spinning.
When you switch off the ESP ®
,
R the ESP ®
does not stabilize the vehicle
R the engine output is not limited, which
allows the drive wheels to spin and thus cut
into surfaces for better grip
R the 4-ETS will still apply the brakes to a
spinning wheel
R the ESP ®
continues to operate when you
are braking
R the cruise control or the Distronic system
cannot be activated
R the cruise control or the Distronic system
switch off if activated
i When the ESP ®
is switched off and one or
more drive wheels are spinning, the ESP ®
warning lamp d in the instrument
cluster flashes. However, the ESP ®
will
then not stabilize the vehicle. X
With the engine running, press ESP ®
switch : until the ESP ®
warning lamp
d in the instrument cluster comes on.
The ESP ®
is switched off. G
Warning!
When the ESP ®
warning lamp d is
illuminated continuously, the ESP ®
is
switched off or is not operational due to a
malfunction. Vehicle stability in standard
driving maneuvers is reduced.
Adapt your speed and driving to the prevailing
road conditions and to the non-operating
status of the ESP ®
.
! Avoid spinning of a drive wheel for an
extended period with the ESP ®
switched
off. This may cause serious damage to the
drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
Switching on the ESP ® X
Press ESP ®
switch : until the ESP ®
warning lamp d in the instrument
cluster goes out.
You are now again in normal driving mode
with the ESP ®
switched on.
ESP ®
trailer stabilization If the trailer you are towing should begin to
sway, the rig can only be stabilized by
immediately applying the brakes hard.
Steering during this maneuver will not help to
stabilize the rig.66
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The ESP
®
will assist you in such situations.
The ESP ®
recognizes when the trailer starts
swaying and will apply the brakes to reduce
the
vehicle speed to a non-critical speed that
allows the vehicle-trailer combination to
stabilize.
The ESP ®
trailer stabilization is functional at
vehicle speeds above approximately 40 mph
(65 km/h) when the ESP ®
is switched on. G
Warning!
The system will not be able to assist when the
trailer jackknifes
R if the ESP ®
has switched off due to a
malfunction
R on wet or icy roads
R on roads with slippery surface
R in sand or gravel
Trailers with a high center of gravity may tip
over

before the system recognizes swaying of
the trailer. Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
SmartKey that is left inside the vehicle.
Activating X
With SmartKey: Remove the SmartKey
from the starter switch.
X With KEYLESS-GO:
Turn off the engine and
open the driver’s door.
Deactivating X
Switch on the ignition.
i Starting the engine will also deactivate
the immobilizer. In the event that the engine cannot be
started (yet the vehicle’s battery is
charged), the system is not operational.
Contact an authorized Mercedes-Benz
Center

or call 1-800-FOR-MERCedes (in the
USA) or 1-800-387-0100 (in Canada). Anti-theft alarm system
Once the alarm system has been armed, a
visual and audible alarm is triggered when
someone opens
R a door
R the tailgate
R the hood
The alarm will stay on even if the activating
element, a door, for example, is closed
immediately.
The

alarm system will also be triggered when
R the vehicle is opened with the mechanical
key
R a door is opened from the inside
To cancel the alarm after it has been
triggered, see “Canceling the alarm”
(Y page 68).
i If the alarm stays on for more than
30 seconds, the Tele Aid system initiates a
call to the Response Center automatically.
The Tele Aid system will initiate the call
provided that
R you have subscribed to the Tele Aid
service
R the Tele Aid service has been activated
properly
R the necessary mobile phone, power
supply and GPS coverage are available Anti-theft systems
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X
Arming: Lock the vehicle with the
SmartKey or with KEYLESS-GO.
The turn signal lamps flash three times to
indicate that the vehicle is locked. Indicator
lamp : flashes to indicate that the alarm
system is armed.
i If the turn signal lamps do not flash three
times, a door or the tailgate may not be
properly closed.
Close the respective element.
X Disarming: Unlock the vehicle with the
SmartKey or with KEYLESS-GO.
The turn signal lamps flash once to indicate
that the alarm system is disarmed.
i Unless you open a door or the tailgate
within approximately 40 seconds after
unlocking the vehicle:
R The vehicle will be locked again.
R The anti-theft alarm system will be
rearmed. Canceling the alarm
To cancel the alarm, do one of the following:
X Insert the SmartKey into the starter switch.
X Press button % or & on the
SmartKey.
In vehicles with KEYLESS-GO:
X Grasp an outside door handle. The SmartKey must be within 3 ft (1 m) of
the vehicle.
X Press the KEYLESS-GO start/stop button.
The SmartKey must be inside the vehicle. 68
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