2007 MERCEDES-BENZ GL450 Owner's Manual

104 Safety and Security
Driving safety systems
Braking
At the instant one of the wheels is about to
lock up, a slight pulsation can be felt in the
brake pedal, indicating that the ABS is in
the regulating mode.
Keep firm and steady pressure on the
brake pedal while experiencing the pul-
sation.
Continuous, steady brake pedal pressure
yields the advantages provided by the ABS,
namely braking power and 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
Keep continuous full pressure on the
brake pedal.
Off-road – ABS
With the off-road driving program switched
on (
page 279), or with the transmission
in LOW RANGE* mode (
page 203), the
ABS designed for off-road use is automati-
cally activated.
When applying the brakes at speeds below
approximately 18 mph (30 km/h), the
front wheels are locked cyclically to short-
en the braking distance (dig-in effect). This
affects steering the vehicle.
For more information, see “Practical hints”
(
page 435).
Warning!G
When the ABS is malfunctioning, the BAS,
the ESP®, and the 4-ETS are also switched
off. The basic driving and braking functions
are still available.
When the ABS is malfunctioning, the wheels
may lock during hard braking, reducing
steering capability and extending the brak-
ing distance.
Warning!G
The ABS cannot prevent the natural laws of
physics from acting on the vehicle, nor can
it increase braking or steering efficiency be-
yond that afforded by the condition of the
vehicle brakes and tires or the traction
afforded. The ABS cannot prevent acci-
dents, including those resulting from
excessive speed in turns, following another
vehicle too closely, or hydroplaning. Only a
safe, attentive, and skillful driver can pre-
vent accidents. The capabilities of an ABS
equipped vehicle must never be exploited in
a reckless or dangerous manner which
could jeopardize the user’s safety or the
safety of others.

105 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. It 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
®
works to stabilize the vehicle. The ESP® is
especially useful while driving off and on
wet or slippery road surfaces. The ESP
®
also helps stabilize 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.

106 Safety and Security
Driving safety systems
For more information, see the “Practical
hints” section (
page 441) and
(
page 459).
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-
ties of an ESP
® equipped vehicle must never
be exploited in a reckless or dangerous
manner which could jeopardize the user’s
safety or the safety of others.
!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.
iThe ESP® will only function properly if you
use wheels of the recommended tire size
(
page 554).

107 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.

108 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 279), or with the transmission
in LOW RANGE* mode (
page 203), 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.

109 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 471).
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 279) or LOW RANGE*
mode (
page 203).
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.

110 Safety and Security
Driving safety systems
For more information, see the “Practical
hints” section (
page 436) and
(
page 451).
Off-road - 4-ETS
With the off-road driving program switched
on (
page 279), or with the transmission
in LOW RANGE* mode (
page 203), 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 inoperative See Operator’s
Manual
appears in the multifunction display.

111 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 500)

a door is opened from the inside, see
“Opening the doors from the inside”
(
page 122)
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 332) provided that the Tele Aid service
was subscribed to and properly activated, and
that necessary cellular service and GPS cover-
age are available.