2010 MERCEDES-BENZ R320 ECU

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
Driving safety systems
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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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Opening the doors from the inside
You can open a door from the inside even
when it is locked unless it is secured with the
child safety lock ( Y page 61).
Open door only when conditions are safe to
do so. Example illustration driver’s door
If the vehicle has previously been locked with
the SmartKey or with KEYLESS-GO, opening
a door from the inside will trigger the anti-
theft alarm system.
To cancel the alarm, see (
Y page 68).
X Front doors: Pull on inside door
handle ; on the respective front door.
If the door was locked, locking knob : will
move up.
X Rear doors: Pull up locking knob on the
respective rear door to unlock door.
X Pull on the inside door handle on the
respective rear door. Automatic central locking
The doors and the tailgate lock automatically
when the vehicle is set into motion.
You can open a locked front door from the
inside. Open door only when conditions are
safe to do so.
The doors are designed to unlock
automatically after an accident if the force of
the impact exceeds a preset threshold.
The vehicle locks automatically when the
ignition is switched on and the wheels are turning at vehicle speeds of above 9 mph
(15 km/h). You could therefore lock yourself
out when the vehicle is pushed or towed or is
on a test stand.
i
You can also activate or deactivate the
automatic central locking using the control
system (Y page 137). Locking and unlocking from the inside
G
Observe Safety notes, see page 55.
You can lock or unlock the vehicle from the
inside using the central locking switches. This
can be useful, for example, if you want to lock
the vehicle before starting to drive.
The central locking switches do not lock or
unlock the fuel filler flap.
The switches are located in each front door. X
Locking: Press central locking switch ;.
When all doors and the tailgate are closed,
the vehicle locks.
X Unlocking: Press central unlocking
switch :.
You can open a locked front door from the
inside at any time. Open door only when
conditions are safe to do so. 74
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the door-mounted remote tailgate switch.
Monitor the closing procedure carefully to
make sure no one is in danger of being
injured.
To interrupt the closing procedure, press or
pull the door-mounted remote tailgate switch.
If the tailgate comes into contact with an
object while closing, the closing procedure is
stopped and the tailgate reopens. This may
happen if luggage has been piled too high, for
example.
X Turn the SmartKey in the starter switch to
position 1 or 2.
X Press remote tailgate opening/closing
switch : until the tailgate begins to close.
While the tailgate is closing an acoustic
warning sounds.
X Interrupting the closing procedure:
Press or pull remote tailgate opening/
closing switch :.
Limiting opening height of tailgate You can limit the opening height of the
tailgate in the upper opening range. This can
be useful, for example, when the space above
the tailgate is not sufficient.
Activating
X
Open the tailgate: Pull on handle
(Y page 75) or press and hold button
F on the SmartKey until the tailgate
opens.
X Stop opening procedure: When the
tailgate is in the desired position, press
tailgate closing switch ( Y page 77) or pull
on handle once more.
X You can also press or pull the remote
tailgate opening/closing switch
(Y page 78) to stop the opening procedure. X
Press and hold the tailgate closing switch
in the tailgate ( Y page 77) until you hear a
short acoustic signal.
The opening height of the tailgate is limited.
The tailgate will now stop at the stored
position when opened.
Deactivating
X Press and hold the tailgate closing switch
in the tailgate ( Y page 77) until you hear
two short, consecutive acoustic signals. Starter switch positions
SmartKey
G
Observe Safety notes, see page 55. Starter switch
g
For removing SmartKey
1 Power supply for some electrical
consumers, e.g. radio
2 Ignition (power supply for all electrical
consumers) and driving position
3 Starting position
When you switch on the ignition, all lamps
(except low-beam headlamp indicator lamp,
high-beam headlamp indicator lamp, and turn
signal indicator lamps unless activated) in the
instrument cluster come on. If a lamp in the
instrument cluster fails to come on when the
ignition is switched on, have it checked and
replaced if necessary. If a lamp in the
instrument cluster remains on after starting
the engine or comes on while driving, refer to
“Lamps in instrument cluster” (Y page 299). Starter switch positions
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R
Adjust the head restraint so that it is as
close
to the head as possible. The center of
the head restraint must support the back of
the head at eye level.
R Never place hands under the seat or near
any moving parts while a seat is being
adjusted.
Failure to do so could result in an accident
and/or serious personal injury. G
Warning!
The power seats can be operated at any time.
Therefore, do not leave children unattended
in the vehicle, or with access to an unlocked
vehicle. A child’s unsupervised access to a
vehicle could result in an accident and/or
serious personal injury. G
Warning!
According to accident statistics, children are
safer when properly restrained in the rear
seating positions than in the front seating
position. Thus, we strongly recommend that
children

be placed in the rear seats whenever
possible. Regardless of seating position,
children 12 years old and under must be
seated and properly secured in an
appropriately sized infant restraint, toddler
restraint, or booster seat recommended for
the size and weight of the child. For additional
information, see “Children in the vehicle”.
A child’s risk of serious or fatal injuries is
significantly increased if the child restraints
are not properly secured in the vehicle and/
or the child is not properly secured in the child
restraint. G
Warning!
For your protection, drive only with properly
positioned head restraints.
Adjust

the head restraint so that it is as close
to the head as possible and the center of the
head restraint supports the back of the head
at eye level. This will reduce the potential for
injury to the head and neck in the event of an
accident or similar situation. Do not drive the vehicle without the seat head
restraints. Head restraints are intended to
help reduce injuries during an accident.
Seat adjustment
! When moving the seats, make sure there
are no items in the footwell or behind the
seats. Otherwise, you could damage the
seats and/or the items.
Power seats !
When the second-row seats are folded
forward, e.g. for cargo volume expansion,
the front seats may not be moved to the
rearmost position. Otherwise you could
damage the front and second-row seats.
! When

adjusting the seat backrest tilt and
head restraint height, make sure the sun
visor is folded up. If the head restraint is in
the uppermost position, it could hit and
damage the sun visor.
i Vehicles without memory function:
The seats can be adjusted within 5 minutes
after either front door has been opened.
The counter resets each time
R you open or close a front door
R you insert the SmartKey into the starter
switch
R you remove the SmartKey from the
starter switch
R you switch the ignition on or off
Just like in vehicles with memory function,
the power seats can be operated at any
time when the ignition is switched on.
i The memory function (Y page 96) lets
you store the settings for the seat position
together with the settings for the steering
wheel (electrical) and exterior rear view
mirrors. 82
Seats
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