330 Controls in detail
Useful features
Tele Aid*
Shortly after the completion of your Tele 
Aid acquaintance call, you will receive a 
user ID and password. By visiting 
www.mbusa.com and selecting “Tele Aid” 
(USA only), you will have access to account 
information, remote door unlock and 
more.The Tele Aid system
(Tele
matic Alarm Identification on 
D
emand)
The Tele Aid system consists of three 
types of response:
automatic and manual emergency
roadside assistance
information
The Tele Aid system is operational provid-
ing that the vehicle’s battery is charged, 
properly connected, not damaged and cel-
lular and GPS coverage are available.
The speaker volume of a Tele Aid call can 
be adjusted by using the volume control on 
the COMAND system headunit or on the 
multifunction steering wheel. To raise, turn 
the rotary volume control on the COMAND 
system headunit clockwise or press 
buttonæ on the multifunction steering 
wheel. To lower, turn the rotary volume 
control on the COMAND system headunit 
counterclockwise or press buttonç on 
the multifunction steering wheel.
To activate, press the SOS button, the 
Roadside Assistance button• or 
the Information button¡, depend-
ing on the type of response required.
!The initial activation of the Tele Aid system 
may only be performed by completing the sub-
scriber agreement and placing an acquaintance 
call using the ¡button. Failure to complete 
either of these steps will result in a system that 
is not activated.
If you have any questions regarding activation, 
please call the Response Center at 
1-800-756-9018 (in the USA) or 
1-888-923-8367 (in Canada).
iThe SOS button is located in the overhead 
control panel (
page 332).
The Roadside Assistance button• 
(
page 333) and the Information 
button¡(
page 334) are located below 
the center armrest cover.
!The Tele Aid system utilizes the cellular 
network for communication and the GPS (G
lobal 
P
ositioning System) satellites for vehicle 
location. If either of these signals are unavail-
able, the Tele Aid system may not function and if 
this occurs, assistance must be summoned by 
other means. 
332 Controls in detail
Useful features
A voice connection between the Response 
Center and the occupants of the vehicle 
will be established automatically soon 
after the emergency call has been initiat-
ed. 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 
CenterInitiating an emergency call manually
1Cover
2SOS button
Briefly press on cover1.
The cover opens.
Press SOS button2 briefly.
The indicator lamp in SOS button2 
will flash until the emergency call is 
concluded.
Wait for a voice connection to the 
Response Center.
Close cover1 after the emergency 
call is concluded.
iLocation of the vehicle on a map is only 
possible if the vehicle is able to receive signals 
from the GPS satellite network and pass the 
information on to the Response Center.
Warning!G
If the indicator lamp in the SOS button is 
flashing continuously and there was no 
voice connection to the Response Center 
established, then the Tele Aid system could 
not initiate an emergency call (e.g. the rele-
vant cellular phone network is not available). 
The message 
Call failed appears in the 
multifunction display for approximately 
10 seconds.
Should this occur, assistance must be 
summoned by other means. 
451 Practical hints
What to do if …
Symbol messages
Display symbolDisplay messagePossible cause/consequencePossible solution
#The battery is no longer charg-
ing.
Possible causes:
alternator malfunctioning
broken poly-V-belt
Do not forget that the brake 
system requires electrical 
energy and may be operating 
with restricted capability. 
Considerably greater brake 
pedal force is required and the 
stopping distance is increased.
Stop in a safe location or as soon as it is 
safe to do so and check the poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise 
the engine will overheat due to an 
inoperative water pump which may 
result in damage to the engine. 
Contact an authorized 
Mercedes-Benz Light Truck Center.
If it is intact:
Contact an authorized 
Mercedes-Benz Light Truck Center 
immediately. Adjust driving to be 
consistent with reduced braking 
responsiveness. 
452 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
#Battery/Alternator
Stop vehicleThe battery is defective.Stop the vehicle in a safe location or as 
soon as it is safe to do so.
Apply the parking brake (page 66).
Do not continue to drive.
Contact an authorized Mercedes-Benz 
Light Truck Center.
2Brake wearThe brake pads have reached 
their wear limit.Have the brake pads replaced as soon as 
possible.
!Brake pad thickness must be visually in-
spected by a qualified technician at the intervals 
specified in the Maintenance Booklet.