2008 MERCEDES-BENZ R320 warning light

311 Controls in detail
Useful features
Cupholders in third-row side trim
Cupholders are located in the side trims of
the third-row seats.
1Cup holderAshtrays
Your vehicle is equipped with an ashtray
and a cigarette lighter (
page 313)
located in the front center console and an
ashtray located in front of the second-row
seats (
page 312).
Ashtray in the front center console
Opening the ashtray
1Cover
2Chrome label
Tab lightly on chrome label 2 of
cover1.
Cover 1 swings open.
Removing ashtray insert
Warning!G
Remove ashtray insert only with vehicle
standing still. Set the parking brake to
secure vehicle from movement. Set auto-
matic transmission toP. With the automatic
transmission set toP, turn off the engine.

313 Controls in detail
Useful features
1Ashtray cover
2Ashtray insert
Push on ashtray insert 2 and pull it
out upwards.
Reinstalling ashtray insert
Insert ashtray insert 2 into opening.
Push down ashtray insert 2 until it
engages.
Close ashtray cover 1.
Cigarette lighter
Switch on the ignition (page 39).1Cover
2Cigarette lighter
Open cover1 (page 311).
Push in cigarette lighter2.
The cigarette lighter will pop out auto-
matically when hot.
Take out cigarette lighter2.
Warning!G
Never touch the heating element or sides of
the cigarette lighter; they are extremely hot.
Hold the knob only.
Make sure that any children traveling with
you do injure themselves or start a fire with
the hot cigarette lighter.
When leaving the vehicle always remove the
SmartKey or SmartKey with KEYLESS-GO*
from the starter switch, take it with you, and
lock the vehicle. Do not leave children
unattended in the vehicle, or with access to
an unlocked vehicle. A child’s unsupervised
access to a vehicle could result in an
accident and/or serious personal injury.

319 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
approved external antenna. Refer to the
radio transmitter operation instructions
regarding use of an external antenna.When the mobile phone is inserted in the
cradle, you can operate the telephone
using the following devices:

mobile phone keypad

COMAND system (see separate operat-
ing instructions)

buttonss andt on the multi-
function steering wheel (
page 158)

Voice Control System* (see separate
operating instructions)
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,
possibly resulting in an accident and/or
serious personal injury.
Warning!G
Please do not forget that your primary
responsibility 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
recommend that you pull over to a safe loca-
tion and stop before placing or taking a
telephone 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
mobile 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
(approximately 14 m) every second.
1Observe all legal requirements.
iVarious mobile phone cradles can be
installed in the front center armrest, see
separate installation instructions for the mobile
phone cradle. These mobile phone cradles can
be obtained 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
instructions on how to use the mobile phone.

323 Controls in detail
Useful features
System self-check
Initially, after switching on the ignition,
malfunctions are detected and indicated
(the indicator lamps in the SOS button, the
Roadside Assistance button• and the
Information button¡ stay on longer
than 10 seconds or do not come on). The
message
Tele Aid Inoperative appears
in the multifunction display.Emergency calls
An emergency call is initiated auto-
matically following an accident in which
the emergency 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 324) 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 information relevant to the emergency,
such as the location of the vehicle (deter-
mined by the GPS satellite location sys-
tem), vehicle model, identification number
and color are generated.
iWhen a Tele Aid call has been initiated,
the COMAND system audio is muted and the
selected mode (radio, CD etc.) pauses.
The optional cellular phone (if installed) inserted
in cradle switches off. If you must use this
phone, we recommend that you use it only with
the vehicle at a standstill in a safe location.
Remove the phone from the cradle and place the
call. The navigation* system (if engaged) will
continue to run. The display in the instrument
cluster is available for use, and spoken com-
mands are only available by pressing the
RPT button on the COMAND system. A pop-up
window will appear in the COMAND system dis-
play to indicate that a Tele Aid call is in progress.
After the Tele Aid call has ended, the optional
cellular phone inserted in the cradle switches on
again. A PIN entry might be necessary.
Warning!G
If the indicator lamps on the SOS button, on
the Roadside Assistance button, and/or on
the Information button remain illuminated
continuously in red and/or the message
Tele Aid Inoperative is displayed in the
multifunction display after the system
self-check, a malfunction in the system has
been detected.
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.

339 Operation
Driving instructions
Driving instructions
Drive sensibly – save fuel
Fuel consumption, to a great extent,
depends on driving habits and operating
conditions.
To save fuel you should:

Keep tires at the recommended
inflation pressures.

Remove unnecessary loads.

Remove carriers when not in use.

Allow engine to warm up under low
load use.

Avoid frequent acceleration and
deceleration.

Have all maintenance work performed
at the intervals specified in the
Maintenance Booklet and as required
by the Maintenance System. Contact
an authorized Mercedes-Benz Light
Truck Center.
Fuel consumption is also increased by
driving in cold weather, in stop-and-go
traffic, on short trips and in hilly area.
Drinking and drivingPedals
Warning!G
Drinking and driving and/or taking drugs
and driving are a very dangerous combina-
tion. Even a small amount of alcohol or
drugs can affect your reflexes, perceptions
and judgment.
The possibility of a serious or even fatal
accident are greatly increased when you
drink or take drugs and drive.
Do not drink or take drugs and drive or allow
anyone to drive who has been drinking or
taking drugs.
Warning!G
Make sure that absolutely no objects are ob-
structing the pedal’s range of movement.
Keep the driver’s footwell clear of all obsta-
cles. If there are any floormats or carpets in
the footwell, make sure the pedals still have
sufficient clearance.
During sudden driving or braking maneu-
vers, the objects could get caught between
the pedals. You could then no longer brake
or accelerate. This could lead to accidents
and injury.

340 Operation
Driving instructions
Power assistanceBrakes
Warning!G
With the engine not running, there is no
power assistance for the brake and steering
systems. In this case, it is important to keep
in mind that a considerably higher degree of
effort is necessary to brake and steer the ve-
hicle.
Warning!G
After driving in heavy rain for some time
without applying the brakes or through wa-
ter deep enough to wet brake components,
the first braking action may be somewhat
reduced and increased pedal pressure may
be necessary to obtain expected braking
effect. Maintain a safe distance from
vehicles in front.
Resting your foot on the brake pedal will
cause excessive and premature wear of the
brake pads.
It can also result in the brakes overheating,
thereby significantly reducing their effec-
tiveness. It may not be possible to stop the
vehicle in sufficient time to avoid an
accident.
!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 the vehicle is being towed
with one axle raised.
Active braking action through the ESP
® may
otherwise seriously damage the brake system
which is not covered by the Mercedes-Benz
Limited Warranty
!Vehicles with 4MATIC must not be towed
with one axle raised.
!Vehicles with 4MATIC:
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.

341 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
subjected to moderate loads, you should
occasionally 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 101).
Brake pad wear or a leak in the system may
be the reason for low brake fluid level 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 415).
Observe additional messages in the multi-
function display that may appear
(
page 447).
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.
!Vehicles with 4MATIC:
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 test-
ing the parking brake on a brake test dynamom-
eter 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.
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.

342 Operation
Driving instructions
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.Parking brake
When driving on wet roads or dirt covered
surfaces, road salt and/or dirt can get into
the parking brake. To prevent corrosion
and a reduction in the braking power of the
parking brake, observe the following:
From time to time, lightly engage the
parking brake before driving off.
Drive a distance of approximately
110 yds (100 m) at a maximum speed
of 12 mph (20 km/h)
Driving off
Apply the brakes to test them briefly after
driving off. Perform this procedure only
when the road is clear of other traffic.
Warm up the engine smoothly. Do not
place full load on the engine until the oper-
ating temperature has been reached.!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.
Warning!G
While performing this procedure, please as-
sure that the vehicle is stopped before ap-
plying the parking brake. Otherwise the rear
wheels could lock up. You could lose control
of the vehicle and cause an accident. In ad-
dition, the vehicle’s brake lights do not light
up when the parking brake is engaged.
Make sure not to endanger any other road
users when you engage the parking brake.
!When driving off on a slippery surface, do
not allow a drive wheel to spin for an extended
period with the ESP
® switched off. Doing so may
cause serious damage to the drivetrain which is
not covered by the Mercedes-Benz Limited
Warranty.
!Simultaneously depressing the accelerator
pedal and applying the brakes reduces engine
performance and causes premature brake and
drivetrain wear.