2008 MERCEDES-BENZ GL320 brake sensor

260 Controls in detail
Driving systems
Setting to last stored speed
(“Resume” function)
Briefly pull the cruise control lever in di-
rection of arrow4 (
page 256).
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* (Canada only)
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 255).
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.
164.boo Seite 260 Freitag, 30. März 2007 12:54 12

271 Controls in detail
Driving systems
The most likely cause for a malfunctioning
system is a dirty sensor (located behind
the hood grille), especially at times of snow
and ice or heavy rain. In such a case,
Distronic will switch off, and the message
DISTRONIC Currently Unavailable – See
Operator’s Manual
appears in the multi-
function display.
For cleaning and care of the Distronic sen-
sor, see “Cleaning the Distronic* system
sensor cover” (
page 430).Turns and bends
In turns or bends, Distronic may not detect
a moving vehicle in front, or it may detect
one too soon. This may cause your vehicle
to brake late or unexpectedly.Offset driving
A vehicle traveling in your lane but offset
from your direct line of travel may not be
detected by Distronic. There will be insuffi-
cient distance to the vehicle ahead.
iIf the message DISTRONIC Available
Again
appears during driving the dirt (e.g.
slush) has dissolved; Distronic works again, if
you reactivate it (
page 266).
164.boo Seite 271 Freitag, 30. März 2007 12:54 12

288 Controls in detail
Driving systems
When the highway level is reached, the in-
dicator lamps3 (
page 281) goes out.
The following message appears in the mul-
tifunction display for 5 seconds:
Parktronic system*
The Parktronic system is an electronic
parking aid and designed to assist the
driver during parking maneuvers. It visually
and audibly indicates the relative distance
between the vehicle and an obstacle.
The Parktronic system is automatically
activated when you

switch on the ignition or start the
engine
and

release the parking brake
and

set the automatic transmission to
positionD,R, orN
iThe vehicle is lowered automatically to the
highway level if the vehicle speed is above
60 mph (96 km/h).
Warning!G
Parktronic is a supplemental system. It is
not intended to, nor does it replace, the
need for extreme care. The responsibility
during parking and other critical maneuvers
always remains with the driver.
Special attention must be paid to objects
with smooth surfaces or low silhouettes
(e.g. trailer couplings, painted posts, or road
curbs). Such objects may not be detected by
the system and can damage the vehicle.
The operational function of the Parktronic
system can be affected by dirty sensors,
especially at times of snow and ice. See
“Cleaning the Parktronic system sensors”
(
page 430).
Interference caused by other ultrasonic
signals (e.g. working jackhammers, car
wash, or the air brakes of trucks) can cause
the system to send erratic indications, and
should be taken into consideration.
Warning!G
Make sure no persons or animals are in the
area in which you are maneuvering. You
could otherwise injure them.
164.boo Seite 288 Freitag, 30. März 2007 12:54 12

289 Controls in detail
Driving systems
The Parktronic system deactivates at
vehicle speeds exceeding approximately
11 mph (18 km/h). At lower vehicle
speeds the Parktronic system turns on
again.
The Parktronic system also deactivates
when you set the automatic transmission
to positionP or depress the parking brake
pedal.
The Parktronic system monitors the sur-
roundings of your vehicle with six sensors
in the front bumper and four sensors in the
rear bumper.
1Sensors in the front bumperRange of the sensors
To function properly, the sensors must be
free of dirt, ice, snow and slush. Clean the
sensors regularly, being careful not to
scratch or damaging the sensors, see
“Cleaning the Parktronic* system sensors”
(
page 430).
!During parking maneuvers, pay special
attention to objects located above or below the
height of the sensors (e.g. planters or trailer
hitches). The Parktronic system will not detect
such objects at close range and damage to your
vehicle or the object may result.
Ultrasonic signals from outside sources (e.g.
working jackhammers, car wash or the air brakes
of trucks) may impair the operation of the
Parktronic system.
164.boo Seite 289 Freitag, 30. März 2007 12:54 12

292 Controls in detail
Driving systems
Switching off
Press Parktronic switch1.
Indicator lamp2 comes on.
Switching on
Press Parktronic switch1 once more.
Indicator lamp2 goes out.Parktronic system* malfunction
If only the red distance segments illumi-
nate and an acoustic warning sounds,
there is a malfunction in the Parktronic
system. The Parktronic system will auto-
matically switch off after 20 seconds and
the indicator lamp in the Parktronic switch
comes on.
Have the Parktronic system checked
by an authorized Mercedes-Benz Light
Truck Center as soon as possible.
If only the red distance segments illumi-
nate and no acoustic warning sounds, the
Parktronic system sensors are dirty (e.g.
slush, snow or ice) or there is an interfer-
ence from other radio or ultrasonic signals
(e.g. working jackhammers, car wash or
the air brakes of trucks). The Parktronic
system will automatically switch off after
20 seconds and the indicator lamp in the
Parktronic switch comes on.
Switch off the ignition (page 42).
Clean the Parktronic system sensors
(
page 430).
Switch on the ignition (page 42).
or
Check the Parktronic system operation
at another location to rule out interfer-
ence from outside radio or ultrasonic
signals.
iThe Parktronic system switches on
automatically when you switch on the ignition
(
page 42).
Vehicles with original equipment Mercedes-Benz
Trailer Hitch Kit:
The rear Parktronic sensor will automatically
disengage when towing a trailer.
164.boo Seite 292 Freitag, 30. März 2007 12:54 12

402 Operation
Tires and wheels
Switch on the ignition (page 42).
Press buttonj or k on the
multifunction steering wheel until the
current inflation pressures for each tire
appear in the multifunction display.
iPossible differences between the readings
of a tire pressure gauge of an air hose, e.g. gas
station equipment, and the vehicle’s control
system can occur. Usually the readings issued by
the control system are more precise.
iWhen the vehicle has been parked for longer
than 20 minutes, the message
Tire pressure
displayed after driving for a few
minutes.
appears in the multifunction display.
Warning!G
It is the driver’s responsibility to calibrate
the TPMS on the recommended cold infla-
tion pressure. Underinflated tires affect the
ability to steer or brake the vehicle. You
might lose control over the vehicle.
iWith a spare wheel without wheel sensor
mounted, the system may still indicate the tire
inflation pressure of the removed wheel for some
minutes. If this happens, keep in mind that the
indicated value where the spare wheel is mount-
ed does not reflect the actual spare tire inflation
pressure.
Warning!G
The TPMS does not indicate a warning for
wrongly selected inflation pressures. Always
adjust tire inflation pressure according to
the Tire and Loading Information placard on
the driver’s door B-pillar or, if available, the
supplemental tire inflation pressure infor-
mation on the inside of the fuel filler flap.
The TPMS is not able to issue a warning due
to a sudden dramatic loss of pressure (e.g.
tire blowout caused by a foreign object). In
this case bring the vehicle to a halt by care-
fully applying the brakes and avoiding
abrupt steering maneuvers.
164.boo Seite 402 Freitag, 30. März 2007 12:54 12

428 Operation
Vehicle care
Automatic car wash
You can have your car washed in an auto-
matic car wash from the start. Automatic
car washes without brushes are prefera-
ble.
To protect the filter system, switch the
climate control system (
page 216) or
the automatic climate control system*
(
page 230) to air recirculation mode.
If the vehicle is very dirty, prewash it
before running it through the automatic
car wash.When taking the vehicle through an auto-
matic conveyor type car wash, observe the
following instructions.Vehicles with SmartKey:
With the vehicle at a standstill and the
ignition switched on shift the automatic
transmission to neutral positionN.
If engaged, release the parking brake
(
page 59).
Switch off the ignition and leave the
SmartKey in the starter switch.
Vehicles with KEYLESS-GO*:
With the vehicle at a standstill, depress
the brake pedal and keep it pressed.
With the ignition switched on shift the
automatic transmission to park
positionP.
Release the brake pedal.
Remove the KEYLESS-GO* start/stop
button from the starter switch
(
page 43).
Insert the SmartKey with
KEYLESS-GO* into the starter switch.
Switch on the ignition.
!Do not clean your vehicle in an automatic
touchless car wash which use caustic spray.
Otherwise the caustic spray will damage the
paint or ornamental moldings.
!Make sure that the windshield wiper switch
is set to0 (
page 63). Otherwise, e.g. the rain
sensor could activate and cause the wipers to
move unintentionally. This may lead to vehicle
damage.
Due to the width of the vehicle, fold in exterior
rear view mirrors prior to running the vehicle
through an automatic car wash to prevent
damage to the mirrors.
Warning!G
When leaving the SmartKey or SmartKey
with KEYLESS-GO* in the starter switch, do
not leave children unattended in the vehicle.
It is possible for children to switch on the
ignition which could result in unsupervised
use of vehicle equipment.
A child’s unsupervised access to a vehicle
could result in an accident and/or serious
personal injury.
164.boo Seite 428 Freitag, 30. März 2007 12:54 12

477 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
. 3rd Brake LampThe high mounted brake lamp is
malfunctioning. This message
will only appear if a critical num-
ber of LEDs have stopped work-
ing.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
Active Headlamps
InoperativeThe active Bi-Xenon* headlamp
system is malfunctioning.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
AUTO Light
InoperativeThe light sensor is malfunction-
ing. The headlamps switch on
automatically.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
To switch off the headlamps
(U. S. vehicles only):
In the control system, set lamp operation
to manual mode (
page 144).
Switch off the headlamps using the
exterior lamp switch (
page 143).
Brake Lamp
LeftThe left brake lamp is malfunc-
tioning. A substitute bulb is
being used.Replace the bulb as soon as possible
(
page 511).
Brake Lamp
RightThe right brake lamp is malfunc-
tioning. A substitute bulb is
being used.Replace the bulb as soon as possible
(
page 511).
164.boo Seite 477 Freitag, 30. März 2007 12:54 12