2008 MERCEDES-BENZ GL550 service

316 Controls in detail
Useful features
Closing CD changer
1CD changer
Gently push CD changer1 up in
direction of arrow until it engages.
For information on CD changer operation,
see separate COMAND system operating
instructions.Locking and unlocking the glove box
separately
You can lock the glove box separately, e.g.
when the vehicle is in the shop for service.
Take the mechanical key out of the
SmartKey or SmartKey with
KEYLESS-GO* (
page 496).
1Unlocking glove box
2Locking glove box
Insert mechanical key into glove box
lock.
Turn mechanical key to position2 to
lock the glove box.
Turn mechanical key to position1 to
unlock the glove box.
iThe glove box can only be locked or
unlocked with the mechanical key (
page 496).
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328 Controls in detail
Useful features
Telephone*
Radio transmitters, such as a portable tele-
phone or a citizens band unit, should only
be used inside the vehicle if they are con-
nected to an antenna that is installed on
the outside of the vehicle.
The external antenna must be approved by
Mercedes-Benz. Please contact an autho-
rized Mercedes-Benz Light Truck Center
for information on the installation of an ap-
proved external antenna. Refer to the radio
transmitter operation instructions regard-
ing use of an external antenna.When the mobile phone is inserted in the
cradle, you can operate the telephone us-
ing the following devices:

mobile phone keypad

COMAND system (see separate operat-
ing instructions)

buttonss andt on the multi-
function steering wheel (
page 156)

Voice Control System* (see separate
operating instructions)
Please note that these functions are only
available with Mercedes-Benz approved
mobile phones.
Warning!G
Never operate radio transmitters equipped
with a built-in or attached antenna (i.e. with-
out being connected to an external antenna)
from inside the vehicle while the engine is
running. Doing so could lead to a malfunc-
tion of the vehicle’s electronic system, pos-
sibly resulting in an accident and/or serious
personal injury.
Warning!G
Please do not forget that your primary re-
sponsibility is to drive the vehicle. A driver’s
attention to the road must always be
his /her primary focus when driving. For
your safety and the safety of others, we rec-
ommend that you pull over to a safe location
and stop before placing or taking a tele-
phone call.
If you choose to use the telephone
1 while
driving, please use the hands-free device
and only use the telephone when road,
weather and traffic conditions permit. Some
jurisdictions prohibit the driver from using a
cellular telephone while driving a vehicle.
Only operate the COMAND system
1 if road,
weather and traffic conditions permit.
Bear in mind that at a speed of just 30 mph
(approximately 50 km/h), your vehicle is
covering a distance of 44 feet (approximate-
ly 14 m) every second.
1Observe all legal requirements.
iVarious mobile phone cradles can be in-
stalled in the front center armrest, see separate
installation instructions for the mobile phone
cradle. These mobile phone cradles can be ob-
tained from an authorized Mercedes-Benz Light
Truck Center.
The functions and services available to you while
using the mobile phone depend on your service
provider and the type of mobile phone you are
using. See also separate operating manual for in-
structions on how to use your mobile phone.
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333 Controls in detail
Useful features
Emergency calls
An emergency call is initiated automatical-
ly following an accident in which the emer-
gency tensioning devices (ETDs) or
air bags deploy.
An emergency call can also be initiated
manually by opening the cover next to the
interior rear view mirror labeled SOS, then
briefly pressing the button located under
the cover. See (
page 334) for
instructions on initiating an emergency call
manually.Once the emergency call is in progress, the
indicator lamp on the SOS button will
begin to flash. The message
Connecting Call appears in the multifunc-
tion display. When the connection is estab-
lished, the message
Call Connected
appears in the multifunction display. All in-
formation relevant to the emergency, such
as the location of the vehicle (determined
by the GPS satellite location system), vehi-
cle model, identification number and color
are generated.
A voice connection between the Response
Center and the occupants of the vehicle
will be established automatically soon af-
ter the emergency call has been initiated.
The Response Center will attempt to
determine more precisely the nature of the
accident provided they can speak to an
occupant of the vehicle.The Tele Aid system is available if

it has been activated and is operation-
al. Activation requires a subscription
for monitoring services, connection
and cellular air time

vehicle battery power is available

the relevant cellular phone network
and GPS signals are available and pass
the information on to the Response
Center
If a malfunction is indicated as outlined
above, the system may not operate as
expected. Have the system checked at the
nearest Mercedes-Benz Light Truck Center
as soon as possible.
iLocation of the vehicle on a map is only pos-
sible if the vehicle is able to receive signals from
the GPS satellite network and pass the informa-
tion on to the Response Center.
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335 Controls in detail
Useful features
Roadside Assistance button•
The Roadside Assistance button• is
located below the center armrest cover.
1Roadside Assistance button•
Open the storage compartment
(
page 318).
Press and hold button1 (for longer
than 2 seconds).
A call to a Mercedes-Benz Roadside
Assistance dispatcher will be initiated.
The button will flash while the call is in
progress. The message
Connecting Call will appear in the
multifunction display.When the connection is established, the
message
Call Connected appears in the
multifunction display. The Tele Aid system
will transmit data generating the vehicle
identification number, model, color and
location (subject to availability of cellular
and GPS signals).
A voice connection between the Roadside
Assistance dispatcher and the occupants
of the vehicle will be established.
Describe the nature of the need for as-
sistance.The Mercedes-Benz Roadside Assistance
dispatcher will either dispatch a qualified
Mercedes-Benz technician or arrange to
tow your vehicle to the nearest
Mercedes-Benz Light Truck Center. For
services such as labor and/or towing,
charges may apply. Refer to the Roadside
Assistance Manual for more information.
The following is only available in the USA:

Sign and Drive services: Services such
as jump start, a few gallons of fuel or
the replacement of a flat tire with the
vehicle spare tire are obtainable.
iWhile the call is connected you can change
to the navigation menu by pressing the NAV
button on the COMAND system unit.
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337 Controls in detail
Useful features
Call priority
If other service calls such as a Roadside
Assistance call or Information call are
active, an Emergency call is still possible.
In this case, the Emergency call will take
priority and override all other active calls.Remote door unlock
In case you have locked your vehicle unin-
tentionally (e.g. SmartKey inside vehicle),
and the reserve SmartKey is not handy:
Contact the Mercedes-Benz Response
Center at 1-800-756-9018 (in the USA)
or 1-888-923-8367 (in Canada).
You will be asked to provide your pass-
word which you provided when you
completed the subscriber agreement.
Then return to your vehicle and pull the
tailgate recessed handle for minimum
of 20 seconds until the SOS button is
flashing.
The message
Connecting Call ap-
pears in the multifunction display.
iThe indicator lamp in the Information
button¡ remains illuminated in red for
approximately 10 seconds during the system
self-check after switching on the ignition (togeth-
er with the SOS button and the Roadside
Assistance button•).
See system self-check (
page 332) if the indi-
cator lamp does not come on in red or stays on
longer than approximately 10 seconds.
If the indicator lamp in the Information
button¡ is flashing continuously and there
was no voice connection to the Response Center
established, then the Tele Aid system could not
initiate an Information call (e.g. the relevant cel-
lular phone network is not available). The mes-
sage
Call Failed appears in the multifunction
display.
Information calls can be terminated using
thet button on the multifunction steering
wheel or the END button on the COMAND sys-
tem.
!If the indicator lamps do not start flashing
after pressing one of the buttons or remain illu-
minated (in red) at any time, the Tele Aid system
has detected a malfunction or the service is not
currently active, and may not initiate a call. Visit
your authorized Mercedes-Benz Light Truck
Center and have the system checked or contact
the Response Center at 1-800-756-9018 (in the
USA) or 1-888-923-8367 (in Canada) as soon as
possible.
iThe indicator lamp in the respective button
flashes until the call is concluded. Emergency
calls can only be terminated by a Response
Center or Customer Assistance Center repre-
sentative, whereas Roadside Assistance and
Information calls can also be terminated by
pressing buttont on the multifunction
steering wheel or using the END button on the
COMAND system.
!If the indicator lamp continues to flash or
the system does not reset, contact the Response
Center at 1-800-756-9018 (in the USA) or
1-888-923-8367 (in Canada), or Mercedes-Benz
Customer Assistance at 1-800-FOR-MERCedes
(1-800-367-6372) in the USA or Customer
Service at 1-800-387-0100 in Canada.
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338 Controls in detail
Useful features
As an alternative, you may unlock the vehi-
cle via Internet using the ID and password
sent to you shortly after the completion of
your acquaintance call.
The Response Center will then unlock your
vehicle with the remote door unlocking
feature.Stolen Vehicle Recovery services
In the event your vehicle was stolen:
Report the incident to the police.
The police will issue a numbered
incident report.
Pass this number on to the
Mercedes-Benz Response Center along
with your password issued to you when
you subscribed to the service.
The Response Center will then attempt
to covertly contact the vehicle’s
Tele Aid system. Once the vehicle is
located, the Response Center will
contact the local law enforcement and
you. The vehicle’s location will only be
provided to law enforcement.
If you have any questions, please call the
Response Center at 1-800-756-9018 (in
the USA) or 1-888-923-8367 (in Canada).
Garage door opener
The integrated remote control is capable of
operating up to three separately controlled
devices. It provides a convenient way to re-
place up to three hand-held remote con-
trols used to operate devices such as
garage door openers, gate openers, or oth-
er devices compatible with HomeLink
® or
some other systems.
Before the integrated remote control can
be used, it must be programmed to the ga-
rage door opener, gate operator or other
device you wish to operate. See the follow-
ing instructions for programming informa-
tion.iThe remote door unlock feature is available
if the relevant cellular phone network is avail-
able.
The SOS button will flash and the message
Connecting Call will appear in the multifunc-
tion display to indicate receipt of the door unlock
command.
Once the vehicle is unlocked, a Response Center
specialist may attempt to establish voice contact
with the vehicle occupants.
If the tailgate recessed handle was pulled for
m o r e t h a n 2 0 s e c o n d s b e f o r e d o o r u n l o c k a u t h o -
rization was received by the Response Center,
you must wait 15 minutes before pulling the tail-
gate recessed handle again.
iWhen the anti-theft alarm stays on for more
than 30 seconds, a call is initiated automatically
to the Response Center. See anti-theft alarm
system (
page 109).
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343 Controls in detail
Useful features
Programming tips
If you are having difficulty programming
the integrated remote control, here are
some helpful tips:

Check the frequency of hand-held
remote control5 (typically located on
the reverse side of the remote). The in-
tegrated remote control is compatible
with radio-frequency devices operating
between 280-390 MHz.

Put a new battery in hand-held remote
control5. This will increase the likeli-
hood of the hand-held remote control
sending a faster and more accurate sig-
nal to the integrated remote control.

While performing step 3, hold
hand-held remote control5 at differ-
ent lengths and angles from the signal
transmitter button (2, 3 or4) you
are programming. Attempt varying
angles at the distance of 2 to 5 in
(5 to 12 cm) away or the same angle at
varying distances.

If another hand-held remote control is
available for the same device, try the
programming steps again using that
other hand-held remote control. Make
sure new batteries are in the hand-held
remote control before beginning the
procedure.

Straighten the antenna wire from the
garage door opener assembly. This
may help improve transmitting and/or
receiving signals.
iCertain types of garage door openers are in-
compatible with the integrated remote control. If
you should experience further difficulties with
programming the integrated remote control,
contact an authorized Mercedes-Benz Light
Truck Center, or call Mercedes-Benz Customer
Assistance Center (in the USA only) at
1-800-FOR-MERCedes, or Customer Service (in
Canada) at 1-800-387-0100.
iUSA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the following
two conditions:
(1) This device may not cause harmful interfer-
ence, and
(2) this device must accept any interference
received, including interference that may
cause undesired operation.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.
iCanada only:
This device complies with RSS-210 of Industry
Canada. Operation is subject to the following
two conditions:
(1) This device may not cause interference, and
(2) this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Any unauthorized modification to this device
could void the user’s authority to operate the
equipment.
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349 Operation
Driving instructions
To help prevent brake disk corrosion after
driving on wet road surfaces (particularly
salted roads), it is advisable to brake the
vehicle with considerable force prior to
parking. The heat generated serves to dry
the brakes.
If your brake system is normally only sub-
jected to moderate loads, you should occa-
sionally test the effectiveness of the
brakes by applying above-normal braking
pressure at higher speeds. This will also
enhance the grip of the brake pads.
Refer to the description of the Brake Assist
System (BAS) (
page 103).Brake pad wear or a leak in the system may
be the reason for low brake fluid in the
reservoir.
The brake fluid level in the reservoir may
be too low if the brake warning lamp in the
instrument cluster comes on and an
acoustic warning sounds although the
parking brake is released (
page 437).
Observe additional messages in the multi-
function display that may appear
(
page 469).
Have the brake system inspected
immediately. Contact an authorized
Mercedes-Benz Light Truck Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact an authorized
Mercedes-Benz Light Truck Center.
Only install brake pads and brake fluid
recommended by Mercedes-Benz.
After hard braking, it is advisable to drive
on for some time, rather than immediately
park, so that the air stream will cool down
the brakes faster.
Warning!G
Make sure not to endanger any other road
users when carrying out these braking
maneuvers.
Warning!G
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that
safe braking is substantially impaired. This
could result in an accident.
!When driving down long and steep grades,
relieve the load on the brakes by shifting into a
lower gear to use the engine’s braking power.
This helps prevent overheating of the brakes and
reduces brake pad wear.
When using the engine’s braking power, a drive
wheel may not spin for an extended period of
time, e.g. on slippery road surfaces. This may
cause serious damage to the drivetrain which is
not covered by the Mercedes-Benz Limited
Warranty.
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