2007 MERCEDES-BENZ GL450 Brake

203 Controls in detail
Transfer case
Transfer case
LOW RANGE mode*
The LOW RANGE mode is available on vehi-
cles with enhanced off-road package*.
In the following situations you should
switch to LOW RANGE mode:

during off-road driving (page 357)

when crossing water (page 362)

when towing up or down on steep
gradients
With the LOW RANGE selected, the
engine’s power delivery and the shifting
behavior of the automatic transmission are
adjusted. Furthermore, the ABS, ESP
® and
4-ETS functions especially adapted to
off-road travel are activated.
For information on driving safety systems
during LOW RANGE mode, see “Driving
safety systems” (
page 103).
For more information on Off-road driving,
see “Off-road driving” (
page 357).Gear Ranges
There are two possible settings.
!Operational or performance test must only
be conducted on a two-axle dynanometer. 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 vehicle is equipped with full-time
four-wheel drive. Both the front and rear axles
are powered at all times when the vehicle is
being operated.
HIGH
RANGERoad position for all normal
driving situations.
(LOW RANGE mode off)
LOW
RANGEOff-road position for traveling
on rough terrain.
(LOW RANGE mode on)
Also use the off-road position
when driving on-road on steep
gradients, especially when
towing a trailer.
LOW RANGE acts by raising
the engine’s gear ratio. The ve-
hicle travels at roughly third
the speed compared to when
in the HIGH RANGE position,
leading to an increase in the
engine’s drive power.

258 Controls in detail
Driving systems
1Setting current or higher speed
Adjustment in 1 mph increments (to
the resistance point) or 5 mph
increments (past the resistance point)
(Canada: 1 km/h or 10 km/h)
2Setting current or lower speed
Adjustment in 1 mph increments (to
the resistance point) or 5 mph
increments (past the resistance point)
(Canada: 1 km/h or 10 km/h)
3Canceling cruise control
4Resume to last set speed
Warning!G
The cruise control is a convenience system
designed to assist the driver during vehicle
operation. The driver is and must always
remain responsible for the vehicle’s speed
and for safe brake operation.
Only use the cruise control if the road, traffic
and weather conditions make it advisable to
travel at a constant speed.

The use of the cruise control can be
dangerous on winding roads or in heavy
traffic because conditions do not allow
safe driving at a constant speed.

The use of the cruise control can be
dangerous on slippery roads. Rapid
changes in tire traction can result in
wheel spin and loss of control.

Deactivate the cruise control when
driving in fog.
The “Resume” function should only be
operated if the driver is fully aware of the
previously set speed and wishes to resume
this particular preset speed.
Warning!G
The cruise control brakes automatically so
that the set speed is not exceeded. The
brake pedal depresses when the cruise con-
trol engages the brakes.
Keep driver’s foot area clear at all times,
including the area under the brake pedal.
Objects stored in this area may impair pedal
movement which could interfere with the
braking ability of the cruise control system.
Do not place your foot under the brake pedal
– your foot could become caught.
Keep in mind that the cruise control is a con-
venience system designed to assist the driv-
er during vehicle operation. The driver is and
must always remain responsible for the
vehicle’s speed and for safe brake
operation.

259 Controls in detail
Driving systems
Activating cruise control
You can activate the cruise control when
the vehicle speed is above
20 mph (30 km/h).
In the following cases you cannot activate
the cruise control:

when you brake

when you have set the parking brake

when the automatic transmission is set
to positionP, R, or N

if the ESP® is switched off

if the ESP® has switched off due to a
malfunctionSetting current speed
Accelerate or decelerate to the desired
speed.
Briefly lift the cruise control lever in
direction of arrow1 or depress in
direction of arrow2.
The current speed is set.
Remove your foot from the accelerator
pedal.
The cruise control is activated.
The current set speed appears in the
multifunction display for approximately
5 seconds.Canceling cruise control
There are several ways to cancel the cruise
control:
Step on the brake pedal.
The cruise control is canceled. The last
speed set is stored for later use.
or
Briefly push the cruise control lever in
direction of arrow3 (
page 258).
The cruise control is canceled. The last
speed set is stored for later use.
iThe vehicle speed displayed in the speedom-
eter can briefly vary from the speed setting for
the cruise control system.iOn uphill grades, the cruise control may not
be able to maintain the set speed. Once the
grade eases, the set speed will be resumed.
On downhill grades, the cruise control maintains
the set speed by braking with the vehicle’s
braking system. In addition, on longer downhill
grades the automatic transmission will down-
shift automatically.
iThe last stored set speed is deleted when
the engine is turned off.

260 Controls in detail
Driving systems
Setting a higher speed
You can increase the speed in two ways.Adjustment in 1 mph (Canada: 1 km/h)
increments
Briefly lift the cruise control lever up to
the resistance point in direction of
arrow1 (
page 258).
Release the cruise control lever.
The vehicle speed increases in incre-
ments of 1 mph (Canada: 1km/h).
Adjustment in 5 mph
(Canada: 10 km/h) increments
iThe cruise control switches off
automatically when

you step on the brake pedal

you depress the parking brake pedal
The cruise control switches off automatically and
an acoustic warning will sound when

the vehicle speed is below 20 mph
(30 km/h)

the ESP® is in operation

the ESP® is switched off with the ESP®
switch (
page 107)

the ESP® has switched off due to a
malfunction (
page 441)

you set the automatic transmission toN
while driving
Observe additional messages in the
multifunction display that may appear.
!Setting the automatic transmission toN
while driving cancels the cruise control.
However, the automatic transmission should not
be set toN while driving except to coast when
the vehicle is in danger of skidding (e.g. on icy
roads).
iDepressing the accelerator pedal does not
deactivate the cruise control. After a brief accel-
eration (e.g. for passing), the cruise control will
resume the last set speed.
Warning!G
If you increase the set vehicle speed, keep in
mind that it may take a brief moment until
the vehicle has reached the set speed.
Increase the set vehicle speed to a value
that the prevailing road conditions and legal
speed limits permit. Otherwise, sudden and
unexpected acceleration of the vehicle
could cause an accident and/or serious in-
jury to you and others.
iThe set value is increased in 1 mph
(Canada: 1 km/h) increments each time you lift
the cruise control lever up to the resistance
point.
iThe set value is increased in
5 mph (Canada: 10 km/h) increments each time
you lift the cruise control lever past the
resistance point.

261 Controls in detail
Driving systems
Briefly lift the cruise control lever up
past the resistance point in direction of
arrow1 (
page 258).
Release the cruise control lever.
The vehicle speed increases in incre-
ments of 5 mph (Canada: 10 km/h).
Setting a lower speedYou can reduce the speed in two ways.
Adjustment in 1 mph (Canada: 1 km/h)
increments
Briefly press the cruise control lever
down to the resistance point in direc-
tion of arrow2 (
page 258).
Release the cruise control lever.
The vehicle speed decreases in incre-
ments of 1 mph (Canada: 1 km/h).Adjustment in 5 mph
(Canada: 10 km/h) increments
Briefly press the cruise control lever
down past the resistance point in direc-
tion of arrow2 (
page 258).
Release the cruise control lever.
The vehicle speed decreases in incre-
ments of 5 mph (Canada: 10 km/h).
iThe new speed is set and the vehicle will
accelerate. Keep in mind that it may take a brief
moment until the vehicle has reached the set
speed.
Warning!G
If you decrease the set vehicle speed, keep
in mind that it may take a brief moment until
the vehicle has reached the set speed.
Decelerate the set vehicle speed to a value
that the prevailing road conditions and legal
speed limits permit. Otherwise, sudden and
unexpected deceleration of the vehicle
could cause an accident and/or serious in-
jury to you and others.
iWhen you use the cruise control lever to
decelerate, the brake system will automatically
brake the vehicle if the engine’s braking power
does not brake the vehicle sufficiently.
iThe set value is decreased in 1 mph
(Canada: 1 km/h) increments each time you
press the cruise control lever down to the resis-
tance point.
iThe set value is decreased in 5 mph
(Canada: 10 km/h) increments each time you
press the cruise control lever down past the
resistance point.
iThe new speed is set and the vehicle will
decelerate. Keep in mind that it may take a brief
moment until the vehicle has reached the set
speed.

262 Controls in detail
Driving systems
Setting to last stored speed
(“Resume” function)
Briefly pull the cruise control lever in di-
rection of arrow4 (
page 258).
The cruise control resumes to the last
set speed, or if no speed is stored, it
will set and store the current speed.
Remove your foot from the accelerator
pedal.
The last set speed appears in the multi-
function display for approximately
5 seconds.
Distronic*
When activated, the Distronic adaptive
cruise control system increases the driving
convenience afforded by the cruise control
while traveling on expressways and other
major roadways.

If the Distronic distance sensor detects
a slower moving vehicle directly ahead,
your vehicle speed will be reduced so
that you follow that vehicle at your
preset following distance.

If there is no vehicle directly ahead of
you, Distronic will function in the same
way as standard cruise control
(
page 257).
Warning!G
The set speed stored in memory should only
be set again if prevailing road conditions
permit. Possible acceleration or decelera-
tion differences arising from returning to the
preset speed could cause an accident
and/or serious injury to you and others.
Warning!G
Distronic is a convenience system. Its speed
adjustment reduction capability is intended
to make cruise control more effective and
usable when traffic speeds vary. It is not
however, intended to, nor does it, replace
the need for extreme care. The responsibili-
ty for the vehicle’s speed, distance to the
preceding vehicle and, most importantly,
brake operation to ensure a safe stopping
distance, always remains with the driver.
Distronic cannot take road and traffic condi-
tions into account.
Complex driving situations are not always
fully recognized by Distronic. This could
result in wrong or missing distance
warnings.

265 Controls in detail
Driving systems
Distronic displays in the speedometer
dial
1Set speed
If Distronic is activated, one or two cruise
control speed segments come on around
the set speed.1Set speed
2Cruise control speed segments
3Speed of the vehicle ahead
If Distronic detects a vehicle directly
ahead, the cruise control speed
segments2, which represents the differ-
ence from the speed of the preceding
vehicle3 to the driver’s selected set
speed1, appear in the speedometer.If Distronic calculates that there is a dan-
ger of collision:

The distance warning lampl in the
instrument cluster comes on
(
page 27).

An intermittent warning sounds.
Immediately apply the brake to avoid a
collision.
Under no circumstances should the
driver await the intermittent warning
sound before braking. See the follow-
ing warning note.
The intermittent warning sound ceases
and the distance warning lampl
goes out when the necessary distance
to the vehicle ahead is again estab-
lished.
iThe vehicle speed displayed on the speed-
ometer can briefly vary from the speed setting
on the Distronic system.

266 Controls in detail
Driving systems
DISTRONIC menu in the control system
Use the
DISTRONIC menu to display the
current settings for your Distronic system.
The information shown in the multifunction
display depends on whether the Distronic
system is activated or deactivated.
Press buttonè orÿ repeatedly
until one of the following two displays
appears in the multifunction display.
Warning!G
An intermittent warning sounds and the
distance warning lampl in the instru-
ment cluster is illuminated if the Distronic
system calculates that the distance to the
vehicle ahead and your vehicle’s current
speed indicate that Distronic will not be ca-
pable of slowing the vehicle sufficiently to
maintain the preset following distance,
which creates a danger of a collision.
Immediately brake the vehicle to increase
your distance to the preceding vehicle. The
warning sound is intended as a final caution
in which you should intercede with your own
braking inputs to avoid a potentially danger-
ous situation. Do not wait for the operation
of the warning signal to intercede with your
own braking. This will result in potentially
dangerous emergency braking which will
not always result in an impact being avoid-
ed.
Tailgating increases the risk of an accident.
Warning!G
Distronic brakes your vehicle with a maxi-
mum deceleration of 6.5 ft/s2 (2 m/s2). This
corresponds to about 20% of the maximum
deceleration of your vehicle.
Distronic brakes the vehicle in an effort to
restore the preset distance or to maintain
the set speed.
Keep driver’s foot area clear at all times, in-
cluding the area under the brake pedal. Ob-
jects stored in this area may impair pedal
movement which could interfere with the
braking ability of the Distronic system.
Do not place your foot under the brake pedal
– your foot could become caught.
iFor activating or deactivating the Distronic
system, see “Activating Distronic” (
page 268)
or, see “Deactivating Distronic” (
page 270).
For activating or deactivating the Distance warn-
ing function, see “Distance warning function*”
(
page 186).