2008 MERCEDES-BENZ GL550 ECU

105 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 4-ETS 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
instrument 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®
warning lampv in the instrument cluster
flashes. However, the ESP
® will then not
stabilize the vehicle.
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106 Safety and Security
Driving safety systems
Switching on the ESP®
Press ESP® switch1.
The ESP
® warning lampv in the
instrument cluster goes out.
You are now again in normal driving
mode.For more information, see “Practical hints”
(
page 435).
Off-road – ESP
®
With the off-road driving program switched
on (
page 277), or with the transmission
in LOW RANGE* mode (
page 201), the
ESP® designed for off-road use is automat-
ically activated. At speeds below 27 mph
(45 km/h), the ESP
® assists in over-/un-
dersteering, thus improving vehicle trac-
tion.
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.
ESP
® will assist you in such situations.
ESP® recognizes when the trailer starts
swaying and will apply the brakes to re-
duce the vehicle speed to a non-critical
speed that allows the vehicle-trailer combi-
nation to stabilize.The ESP
® Trailer Stabilization is functional
at vehicle speeds above approximately
40 mph (65 km/h) when the ESP
® is
switched on.
Warning!G
When the ESP® warning lampv is
illuminated continuously, the ESP® is
switched off or is not operational due to a
malfunction.
Adapt your speed and driving to the prevail-
ing road conditions and to the non-operating
status of the ESP
®.
!Avoid spinning of a drive wheel for an ex-
tended period of time with the ESP® switched
off. This may cause serious damage to the
drivetrain which is not covered by the
Mercedes-Benz Limited Warranty.
WarningG
The system will not be able to assist when
the trailer jackknifes

on wet or icy roads

on roads with slippery surface

in sand or gravel
Trailers with a high center of gravity may tip
over before the system recognizes swaying
of the trailer.
iIf the ESP® has switched off due to a mal-
function, ESP® cannot stabilize the rig.
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107 Safety and Security
Driving safety systems
EBP
The EBP enhances braking effectiveness
by allowing the rear brakes to supply a
greater proportion of the braking effort
without a loss of vehicle stability.
For more information, see the “Practical
hints” section (
page 438) and
(
page 468).
4-ETS
The 4-Electronic Traction System (4-ETS)
improves the vehicle’s ability to utilize
available traction, especially under
slippery road conditions. The brakes are
applied to the spinning wheel and power is
transferred to the wheel(s) with traction.
The ESP
® warning lampv in the instru-
ment cluster, starts to flash at any vehicle
speed, as soon as a tire loses traction and
the wheel begins to spin.
Warning!G
If the EBP is malfunctioning, the brake sys-
tem is still functioning. However, the rear
wheels may lock during hard braking, caus-
ing you to lose control over the vehicle and
possibly causing an accident. Adjust your
driving style to the non-operating status of
the EBP.
iIf conditions require, switch on off-road
driving program (
page 277) or LOW RANGE*
mode (
page 201).
Warning!G
When you see ESP® warning lampv
flashing in the instrument cluster, then pro-
ceed 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 4-ETS cannot prevent accidents resul-
ting from excessive speed.
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108 Safety and Security
Driving safety systems
For more information, see the “Practical
hints” section (
page 436) and
(
page 449).
Off-road - 4-ETS
With the off-road driving program switched
on (
page 277), or with the transmission
in LOW RANGE* mode (
page 201), the
4-ETS designed for off-road use is auto-
matically activated.
!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.
!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 testing the parking brake
on a brake test dynamometer 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.
iIf the yellow ESP® warning lampv
comes on while driving, the 4-ETS 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.
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109 Safety and Security
Anti-theft systems
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 43) on the starter
switch 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 41).With KEYLESS-GO*
Switch on the ignition (page 42).
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 496)

a door is opened from the inside, see
“Opening the doors from the inside”
(
page 120)
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).
iIf the alarm stays on for more than
30 seconds, a call to the Response Center is
initiated automatically by the Tele Aid system
(
page 331) provided that the Tele Aid service
was subscribed to and properly activated, and
that necessary cellular service and GPS cover-
age are available.
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110 Safety and Security
Anti-theft systems
Arming the alarm system
The alarm system indicator lamp is located
to the lower left of the hazard warning
flasher.
1Alarm system indicator lamp
Lock the vehicle with the SmartKey or
with KEYLESS-GO* (
page 70).
The turn signal lamps flash three times
to indicate that the vehicle is locked.
The alarm system is armed within ap-
proximately 10 seconds. Alarm system
indicator lamp1 flashes.Disarming the alarm system
Unlock the vehicle with the SmartKey
or with KEYLESS-GO* (
page 40).
The turn signal lamps flash once to
indicate that the alarm system is
disarmed. Indicator lamp1 goes out.Canceling the alarm
To cancel the alarm:
With the SmartKey
Insert the SmartKey in the starter
switch.
or
Press theŒ or ‹button on the
SmartKey.
With KEYLESS-GO*
Grasp an outside door handle.
The SmartKey with KEYLESS-GO must
be within 3 ft (1 m) of the vehicle.
or
Press the KEYLESS-GO start/stop
button (
page 43).
The SmartKey with KEYLESS-GO must
be inside the vehicle.
iIf the turn signal lamps do not flash three
times, one of the following elements may not be
properly closed:

a door

the tailgate
Close the respective element and lock the
vehicle again.
iThe alarm system will rearm automatically
again after approximately 40 seconds if neither a
door nor the tailgate is opened.
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133 Controls in detail
Seats
Pull emergency release1 in the
direction of arrow.
Push seat backrest2 forwards.
Open the left door.
Exit the vehicle.
Front seat active head restraints
You cannot remove the active head
restraints on the driver’s and front
passenger’s seat.
For removal of the active head restraints
we recommend that you contact an
authorized Mercedes-Benz Light Truck
Center.
For information on head restraint adjust-
ment, see “Seats” (
page 45).
For information on active head restraints,
see “Active head restraint” (
page 90).
Rear seats
Warning!G
To help avoid personal injury when folding
the seat backrest forward, make sure that
you move both feet and legs all the way back
and out of the way to avoid them contacting
the seat as it pivots forward.
In order to prevent an accident or any other
potentially dangerous situations when open-
ing the rear door and exiting the vehicle,
make sure that you are aware of the traffic
situation at all times.
Warning!G
For your protection, drive only with properly
positioned head restraints.
Adjust the head restraint so that it is 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.
Warning!G
According to accident statistics, children
are safer when properly restrained in the
rear seating positions than in the front seat-
ing position. Thus, we strongly recommend
that children be placed in the rear seats.
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” (
page 91).
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.
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134 Controls in detail
Seats
Rear seat adjustment
Seat backrest tilt (second-row seats)The seat backrest tilt can be set to five
different positions.
The handles for adjusting the seats are
located on the rear of each seat base.
1Adjustment handle
While seated, pull handle1 in direc-
tion of arrow to resistance point and
hold it there.
To move seat backrest back, lean light-
ly against backrest.
Warning!G
Never ride in a moving vehicle with the seat
backrest in an excessively reclined position
as this can be dangerous. You could slide
under the seat belt in a collision. If you slide
under it, the belt would apply force at the ab-
domen or neck. That could cause serious or
fatal injuries. The seat backrest and seat
belts provide the best restraint when the
wearer is in a nearly upright position and
belts are properly positioned on the body.
Your seat must be adjusted so that you can
correctly fasten your seat belt (
page 53).
Never place hands under the seat or near
any moving parts while a seat is being
adjusted.
After adjusting rear seats, make sure

the seats are properly locked

the seat backrests are in an upright po-
sition and are properly locked
Check for secure locking by pushing and
pulling on the seat backrests. If a seat and
seat backrest are not properly locked, the
seat could move forward and the seat back-
rest could fold. The child seat would no long-
er be properly supported or positioned to
provide its intended benefit.
Warning!G
The seat belt only offers its intended protec-
tion when the seat backrest is in a nearly
vertical position and the occupant is sitting
upright. Avoid sitting in positions that pre-
vent the seat belt from being properly posi-
tioned against the body (
page 53). You
should therefore adjust the backrest to a po-
sition as upright as possible.
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