engine MERCEDES-BENZ R350 2008 W251 Owner's Guide

101 Safety and Security
Driving safety systems
BAS
The Brake Assist System (BAS) operates in
emergency situations. If you apply the
brakes very quickly, the BAS automatically
provides full brake boost, thereby poten-
tially reducing braking distance.
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.
ESP®
The Electronic Stability Program (ESP®) is
operational as soon as the engine is run-
ning and monitors the vehicle’s traction
(force of adhesive friction between the
tires and the road surface) and handling.
The ESP
® recognizes when a wheel is
spinning or if the vehicle starts to skid. By
applying brakes to the appropriate wheel
and by limiting engine output, the ESP
®
helps 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 lampv in the instru-
ment cluster (
page 26) flashes when the
ESP® is engaged.
The ESP
® warning lampv in the instru-
ment cluster comes on when you switch on
the ignition. It goes out when the engine is
running.
Warning!G
If the BAS is malfunctioning, the brake sys-
tem is still functioning, but without the addi-
tional brake boost available that BAS would
normally provide in an emergency braking
maneuver. Therefore, the braking distance
may increase.
Warning!G
The BAS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase braking efficiency beyond that
afforded by the condition of the vehicle
brakes and tires or the traction afforded.
The BAS cannot prevent accidents, includ-
ing 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 a BAS equipped vehicle must
never be exploited in a reckless or danger-
ous manner which could jeopardize the
user’s safety or the safety of others.

102 Safety and Security
Driving safety systems
Warning!G
Never switch off the ESP® when you see the
ESP® warning lampv flashing in the in-
strument cluster. In this case, proceed as
follows:

While driving off, apply as little throttle
as possible.

While driving, ease up on the accelera-
tor.

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 result-
ing from excessive speed.
Warning!G
The ESP® cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase the traction afforded. The ESP
®
cannot prevent accidents, including those
resulting from excessive speed in turns, fol-
lowing another vehicle too closely, or hydro-
planing. Only a safe, attentive, and skillful
driver can prevent accidents. The capabili-
t i e s o f a n E S P
® equipped vehicle must never
be exploited in a reckless or dangerous
manner which could jeopardize the user’s
safety or the safety of others.
!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 the vehicle is being towed
with one axle raised.
Active braking action through the ESP
® may
otherwise seriously damage the brake system
which is not covered by the Mercedes-Benz
Limited Warranty
!Vehicles with 4MATIC must not be towed
with one axle raised.
!Vehicles with 4MATIC:
Operational or performance test must only be
conducted on a two-axle dynamometer. If such
tests are necessary, contact an authorized
Mercedes-Benz Light Truck Center. You could
otherwise seriously damage the brake system or
the transfer case which is not covered by the
Mercedes-Benz Limited Warranty.

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.

104 Safety and Security
Driving safety systems
Switching off the ESP®
To improve the vehicle’s traction, switch
off the ESP® in driving situations where it
would be advantageous to have the drive
wheels spin and thus cut into surfaces for
better grip such as:

when driving with snow chains

in deep snow

in sand or gravelWhen you switch off the ESP
®

the ESP® does not stabilize the vehicle

the engine output is not limited, which
allows the drive wheels to spin and
thus cut into surfaces for better grip

the Electronic Traction System will still
apply the brake to a spinning wheel

the ESP® continues to operate when
you are braking

you cannot activate the cruise control
or the Distronic* system

the cruise control or the Distronic*
system switch off if currently activatedThe ESP
® switch is located on the upper
part of the center console.
1ESP
® switch
With the engine running, press ESP®
switch1.
The ESP
®warning lampv in the in-
strument cluster comes on.
The ESP
® is deactivated.
Warning!G
The ESP® should not be switched off during
normal driving other than in the circum-
stances described below. Disabling of the
system will reduce vehicle stability in stan-
dard driving maneuvers.
Do not switch off the ESP
® when a spare
wheel is mounted.
Warning!G
Switch on the ESP® immediately if the afore-
mentioned circumstances do not apply any-
more. Otherwise the ESP
® will not stabilize
the vehicle when it is starting to skid or a
wheel is spinning.
iWhen the ESP® is switched off and one or
more drive wheels are spinning, the ESP® warn-
ing lamp v in the instrument cluster flashes.
However, the ESP
® will then not stabilize the
vehicle.

106 Safety and Security
Anti-theft systems
Immobilizer
The immobilizer prevents unauthorized
persons from starting your vehicle.
Activating
With the SmartKey
Remove the SmartKey from the starter
switch.
With KEYLESS-GO*
Press the KEYLESS-GO start/stop
button (
page 41) once.
The engine is turned off.
Open the driver’s door.Deactivating
With the SmartKey
Turn the SmartKey in the starter switch
to position2 (
page 39).
With KEYLESS-GO*
Switch on the ignition (page 39).
Anti-theft alarm system
Once the alarm system has been armed, a
visual and audible alarm is triggered when
someone opens

a door

the tailgate

the hood
The alarm will stay on, even if the activat-
ing element (a door, for example) is imme-
diately closed.
The alarm system will also be triggered
when

the vehicle is opened with the mechan-
ical key, see “Unlocking the vehicle”
(
page 474)

a door is opened from the inside, see
“Opening the doors from the inside”
(
page 118)
iStarting the engine will also deactivate the
immobilizer.
In case the engine cannot be started (yet the
vehicle’s battery is charged), the system is not
operational. Contact an authorized
Mercedes-Benz Light Truck Center or call
1-800-FOR-MERCedes (in the USA), or
1-800-387-0100 (in Canada).

115 Controls in detail
Locking and unlocking
Important notes on using KEYLESS-GO*

You can also use the SmartKey with
KEYLESS-GO like a normal SmartKey
(
page 110).

You can combine KEYLESS-GO func-
tions with normal SmartKey functions
(e.g. unlocking with KEYLESS-GO and
locking with the ‹button).

Always carry the SmartKey with
KEYLESS-GO with you.

Never store the SmartKey with
KEYLESS-GO together with

electronic items such as a cellular
phone or another SmartKey with
KEYLESS-GO

metallic objects such as coins or
metal foil
Doing so could impair the function of
the KEYLESS-GO system.

To lock or unlock the vehicle, the
SmartKey with KEYLESS-GO must be
located outside the vehicle within
approximately 3 ft (1 m) of the respec-
tive door or the tailgate.

If the vehicle has been parked for more
than 72 hours, you must pull an outside
door handle in order to activate the
KEYLESS-GO function

In order to start the engine with the
SmartKey with KEYLESS-GO:

The SmartKey with KEYLESS-GO
must be located in the vehicle.

The KEYLESS-GO start/stop button
must be inserted in the starter
switch (
page 41).

The brake pedal must be firmly
depressed. Do not depress the
accelerator.

If the SmartKey with KEYLESS-GO is
positioned farther away from the vehi-
cle, the system may no longer recog-
nize the SmartKey with KEYLESS-GO.
The vehicle then cannot be locked or
the engine started via the KEYLESS-GO
system.

If you have started the engine with the
KEYLESS-GO start/stop button
(
page 54), you can turn it off again by

pressing the KEYLESS-GO
start/stop button (
page 66)

inserting the SmartKey into the
starter switch when the vehicle is at
a standstill and the automatic
transmission is in position P
(
page 66)

116 Controls in detail
Locking and unlocking

If the SmartKey with KEYLESS-GO is
removed from the vehicle (e.g. if a
passenger exits the vehicle with the
SmartKey with KEYLESS-GO)

when pressing the KEYLESS-GO
start/stop button or trying to lock
the vehicle with the lock button on
an outside door handle, the mes-
sage
Key Not Detected appears in
the multifunction display

with the engine running, the mes-
sage
Key Not Detected appears in
the multifunction display while
driving off
Find the SmartKey with KEYLESS-GO
or change its present location immedi-
ately (e.g. place it on the front passen-
ger seat or insert it in shirt pocket).

Remember that the engine can be
started by anyone with a SmartKey
with KEYLESS-GO that is left inside the
vehicle.
Possibility 1: (One SmartKey with
KEYLESS-GO in the vehicle, one
SmartKey with KEYLESS-GO outside
the vehicle):
If you leave the SmartKey with
KEYLESS-GO behind when exiting and
locking the vehicle, no message
appears in the multifunction display.
Possibility 2: (One SmartKey with
KEYLESS-GO in the vehicle, no
SmartKey with KEYLESS-GO outside
the vehicle):
When exiting and trying to lock the
vehicle, the message
Key Detected In
Vehicle
will appear in the multifunction
display. The vehicle will not be locked.Factory setting
Global unlocking
Grasp an outside door handle.
All turn signal lamps flash once. The
locking knobs in the doors move up.
The anti-theft alarm system is dis-
armed.
The vehicle will lock again automatically
and rearm the anti-theft alarm system
within approximately 40 seconds of
unlocking if

neither door nor tailgate is opened

the central locking switch is not
activated
iThe vehicle could be inadvertently unlocked
if the SmartKey with KEYLESS-GO is within
3ft(1m) of the vehicle and

an outside door handle is splashed
with water
or

you attempt to clean an outside door handle

119 Controls in detail
Locking and unlocking
Front doors
Pull on inside door handle2 on the
respective front door to open door.
If the door was locked, locking knob1
will move up.
Rear doors
Pull up locking knob1 on the respec-
tive rear door to unlock door.
Pull on inside door handle2 on the re-
spective rear door to open door.
Tailgate/Power tailgate*
A minimum height clearance of
7.2 ft (2.20 m) is required to open the
tailgate.iIf the vehicle has previously been locked
from the outside with the SmartKey or with
KEYLESS-GO*, opening a door from the inside
will trigger the anti-theft alarm system.
To cancel the alarm, do one of the following:
With the SmartKey

Insert the SmartKey in the starter switch.

Press theŒ or ‹button on the
SmartKey.
With KEYLESS-GO*

Grasp an outside door handle.

Press the KEYLESS-GO start/stop button
(
page 41).
The SmartKey with KEYLESS-GO must be
inside the vehicle.
Warning!G
Make sure the tailgate is closed when the
engine is running and while driving.
Among other dangers, deadly carbon
monoxide (CO) gases may enter vehicle
interior resulting in unconsciousness and
death.
!The tailgate swings open upwards automat-
ically. Always make sure there is sufficient over-
head clearance.

129 Controls in detail
Seats
With the easy-entry/exit feature activated,
the steering wheel tilts upwards when you

remove the SmartKey from the starter
switch
or

open the driver’s door with the
SmartKey in starter switch position
0or1(
page 39) or the
KEYLESS-GO* start/stop button in
position1 (
page 41)
Easy-entry/exit feature for third-row
seats
This feature allows for easier access to and
exit from the vehicle’s third-row seats.Easy-entry feature for third-row seats
The releases for the easy-entry feature are
located on the entry side and the back of
each outboard second-row seat.
1Easy-entry lever
iIf the current position for the steering wheel
is in the uppermost tilt position, the steering
wheel will no longer be able to move upward
when the easy-entry/exit feature is activated.
The adjustment procedure is briefly interrupted,
when the engine is started.
Warning!G
Let the system complete the adjustment
procedure before setting the vehicle in mo-
tion. All steering wheel adjustments must be
completed before setting the vehicle in mo-
tion. Driving off with the steering wheel still
adjusting could cause the driver to lose con-
trol of the vehicle.
Warning!G
To help avoid personal injury, the sec-
ond-row seat backrests must be properly
locked either in the upright position or,
when using the expanded cargo compart-
ment, in the fully folded position while the
vehicle is in motion.
!7-seat vehicles*:
Do not use the driver’s side easy-entry/exit fea-
ture for third-row seats when the second-row
middle seat is in armrest position. Otherwise, the
seat belt outlet of the second-row middle seat
could damage the seat backrest of the outboard
seat.


145 Controls in detail
Lighting
Turn the exterior lamp switch to
positionU.
With the SmartKey in starter switch
position1 or the KEYLESS-GO*
start/stop button pressed once, only
the parking lamps and the side marker
lamps will switch on and off depending
on the brightness of the ambient light.
When the engine is running, the low
beam headlamps, the tail and parking
lamps, the license plate lamps, and the
side marker lamps will switch on and
off depending on the brightness of the
ambient light.Daytime running lamp mode
In Canada the daytime running lamp mode
is mandatory and therefore in a constant
mode.
In the USA the daytime running lamp mode
is deactivated by default. Activate the day-
time running lamp mode using the control
system, see “Setting daytime running lamp
mode (USA only)” (
page 177).
Turn the exterior lamp switch to
positionM orU.
When the engine is running, the low
beam headlamps are switched on.
In low ambient light conditions, the
following lamps will switch on addition-
ally:

Tail and parking lamps

License plate lamps

Side marker lampsCanada only:
When the engine is running and you shift
from a driving position to positionN orP
with the vehicle at a standstill, the low
beam headlamps will switch off with a
three-minute delay.
When the engine is running and you

turn the exterior lamp switch to
positionC, the low beam head-
lamps, the tail and parking lamps, the
side marker lamps and the license
plate lamps switch on

turn the exterior lamp switch to
positionB, the manual headlamp
mode has priority over the daytime
running lamp mode
iCanada only:
High beam headlamps are only available with the
exterior lamp switch in position B.
iWith the daytime running lamp mode activat-
ed and the engine running, you cannot switch off
the low beam headlamps manually.
iWith the exterior lamp switch in
positionM orU, you cannot switch on the
high beam headlamps.
The high beam flasher is available at all times.
For nighttime driving, turn the exterior lamp
switch in positionB to permit activation of
the high beam headlamps.