MERCEDES-BENZ R320 2008 W251 Owner's Manual

410 Operation
Vehicle care
Cleaning the panorama roof with
tilt/sliding panel*
The rear part of the panorama roof has a
protective layer on the inside.
Use a soft, clean cloth and a mild
window cleaning solution.
An automotive glass cleaner is recom-
mended.Light alloy wheels
If possible, clean wheels once a week.
Use Mercedes-Benz approved Wheel
Care, a soft bristle brush and a strong
spray of water for cleaning the light al-
loy wheels.Plastic and rubber parts
Use a gentle dishwashing detergent or
mild detergent for delicate fabrics as a
washing solution.
Wipe with a cloth moistened in a luke-
warm solution.
The surface may temporarily change
color. If this is the case, wait for it to
dry.
!Do not use a dry cloth, abrasives, solvents
or cleaners containing solvents. Do not touch
the protective layer with hard objects such as an
ice scraper or ring. Never apply strong force and
only use a soft, non-scratching cloth when clean-
ing the rear part of the tilt/sliding panel*.
Otherwise you may scratch or damage the
protective layer.
!Only use acid-free cleaning materials. Acid
may cause corrosion or damage the clear coat.
!The vehicle should not be parked for an
extended period of time immediately after it has
been cleaned, especially not after the wheel rims
have been cleaned with wheel rim cleaner.
Wheel rim cleaners can lead to increased
corrosion of the brake disks and brake pads.
Non-approved wheel cleaners may also damage
the wheel paint if the car is not driven after
cleaning. Therefore, the vehicle’s brake system
should always be warmed-up before it is parked
after cleaning. To do so, please drive your vehicle
for several minutes to allow the brakes to dry.
When applying Mercedes-Benz approved Tire
Care and Mercedes-Benz approved Wheel Care
products, take care not to spray them on the
brake disks.
Warning!G
Do not use cleaners containing solvents or
cockpit care sprays to clean the cockpit or
the steering wheel. Cleaners containing sol-
vents will make the surface porous and vehi-
cle occupants could suffer serious injuries
from plastic parts coming loose in the event
of air bag deployment.

411 Operation
Vehicle care
Hard plastic trim items
Use Mercedes-Benz approved Interior
Care, a soft, lint-free cloth and apply
with light pressure.
Steering wheel
Wipe with a damp cloth and dry thor-
oughly or clean with Mercedes-Benz
approved Leather Care.Carpets
Use Mercedes-Benz approved Carpet
and Fabric Care for cleaning the
carpets.
Headliner
Use a soft bristle brush or a
dry-shampoo cleaner in case of
excessive dirt.
Seat belts
Only use clear, lukewarm water and
soap.Upholstery
Using aftermarket seat covers or wearing
clothing that have the tendency to give off
coloring (e.g. when wet, etc.) may cause
the upholstery to become permanently dis-
colored. By lining the seats with a proper
intermediate cover, contact-discoloration
will be prevented.
!Never apply strong force and only use a soft,
non-scratching cloth when cleaning the surface.
Do not attempt to wipe the surface with a dry
cloth or sponge.
Otherwise you may scratch or damage the
surface.
!The seat belts must not be treated with
chemical cleaning agents. Do not dry the seat
belts at temperatures above 176°F (80°C) or in
direct sunlight.
Warning!G
Do not bleach or dye seat belts as this may
severely weaken them. In a crash they may
not be able to provide adequate protection.
Warning!G
Only use seat or head restraint covers which
have been tested and approved by
Mercedes-Benz for your vehicle model.
Using other seat or head restraint covers
may interfere with or prevent

deployment of the front side impact air
bags

deployment of the rear side impact air
bags*

activation of the active head restraints
Contact an authorized Mercedes-Benz Light
Truck Center for availability.

412 Operation
Vehicle care
Leather upholstery
Please note that leather upholstery is a
natural product and is therefore subject
to a natural aging process. Leather up-
holstery may also react to certain ambient
influences such as high humidity or high
temperature by showing wrinkles for
example.
Wipe leather upholstery with a damp
cloth and dry thoroughly or clean with
Mercedes-Benz approved Leather
Care.Wood trims
Dampen cloth using water and use
damp cloth to clean wood trims in your
vehicle.
!To avoid damage to leather upholstery:

Wipe with light pressure only.

Do not clean with abrasive cleaning agents
such as scouring milk or powder.

Do not soak the leather upholstery.
As leather is a natural product, it could
otherwise harden or become porous.

Exercise particular care when cleaning
perforated leather as its underside should
not become wet.
!Do not use solvents like tar remover or
wheel cleaner nor polishes or waxes as these
may be abrasive.

413 Practical hints
What to do if …
Where will I find ...?
Unlocking / locking in an
emergency
Resetting activated head restraints
Replacing SmartKey batteries
Replacing bulbs
Replacing wiper blades
Flat tire
Bleeding the fuel system
(diesel engine only)
Battery
Jump starting
Towing the vehicle
Fuses

414 Practical hints
What to do if …
Lamps in instrument clusterGeneral information:
If any of the following lamps in the instru-
ment cluster fails to come on during the bulb self-check when switching on the
ignition, have the respective bulb checked
and replaced if necessary.
ProblemPossible cause/consequenceSuggested solution
-The yellow ABS indicator lamp
comes on while the engine is
running.ABS has detected a malfunction and has
switched off. The BAS and the ESP® are also
switched off (see messages in multifunction
display).
The brake system is still functioning normally
but without the ABS available.
If the ABS control unit is malfunctioning,
other systems such as the navigation
system* or the automatic transmission may
also be malfunctioning.
Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability.
Read and observe messages in the
multifunction display (
page 427).
Have the system checked at an
authorized Mercedes-Benz Light
Truck Center as soon as possible.
Failure to follow these instructions
increases the risk of an accident.
The charging voltage has fallen below
10 volts. The ABS has switched off.
The battery might not be charged sufficiently.When the voltage is above this value
again, the ABS is operational again and
the ABS indicator lamp should go out.
If the ABS indicator lamp does not go out:
Have the generator (alternator) and
the battery checked.

415 Practical hints
What to do if …
ProblemPossible cause/conse-
quenceSuggested solution
-The yellow ABS indicator lamp comes on while
the engine is running.The self-diagnosis has not yet
been completed yet.The indicator lamp will go out after driving
a short distance at a vehicle speed of
above 12 mph (20 km/h).
;(USA only)
3(Canada only)
The red brake warning lamp
comes on while driving and an
acoustic warning sounds.You are driving with the
parking brake set.Release the parking brake
(
page 56).
There is insufficient brake fluid
in the reservoir.Risk of accident! Carefully stop the
vehicle in a safe location or as soon as
it is safe to do so.
Apply the parking brake (page 65).
Contact an authorized
Mercedes-Benz Light Truck Center.
Do not add brake fluid! This will not
solve the problem.
Warning!G
Driving with the brake warning lamp illumi-
nated can result in an accident. Have your
brake system checked immediately if the
brake warning lamp stays on.
Do not add brake fluid before checking the
brake system.Overfilling the brake fluid res-
ervoir can result in spilling brake fluid on hot
engine parts and the brake fluid catching
fire. You can be seriously burned.!If you find that the brake fluid in the brake
fluid reservoir has fallen to the minimum mark or
below, have the brake system checked for brake
pad thickness and leaks.

416 Practical hints
What to do if …
ProblemPossible cause/conse-
quenceSuggested solution
;(USA only)
3(Canada only)
-
v
The red brake warning lamp
comes on while driving. In
addition, the yellow ABS mal-
function indicator lamp, and
the yellow ESP
® warning lamp
come on and an acoustic warn-
ing sounds.
The Electronic Brake Propor-
tioning (EBP) has switched off
due to a malfunction.
The ABS, the BAS, and the
ESP
® are also switched off.
Have the system checked at an autho-
rized Mercedes-Benz Light Truck
Center as soon as possible.
Failure to follow these instructions
increases the risk of an accident.

417 Practical hints
What to do if …
ProblemPossible cause/conse-
quenceSuggested solution
?(USA only)
±(Canada only)
The yellow engine malfunction
indicator lamp comes on while
driving.There is a malfunction in:

The fuel management
system

The ignition system

The emission control
system

Systems which affect
emissions
Such malfunctions may result
in excessive emissions values
and may switch the engine to
its limp-home (emergency
operation) mode.
Have the vehicle checked as soon as
possible by an authorized
Mercedes-Benz Light Truck Center.
An on-board diagnostic connector is
used by the service station to link the
vehicle to the shop diagnostics
system. It allows the accurate identifi-
cation of system malfunctions through
the readout of diagnostic trouble
codes. It is located in the front left area
of the footwell next to the parking
brake pedal.
iSome states may by law require you to visit
a workshop as soon as the engine malfunction
indicator lamp comes on. Check local
requirements.

418 Practical hints
What to do if …
ProblemPossible cause/conse-
quenceSuggested solution
?(USA only)
±(Canada only)
The yellow engine malfunction
indicator lamp comes on while
driving.A loss of pressure has been
detected in the fuel system.
The fuel cap may not be closed
properly or the fuel system
may be leaky.Check the fuel cap (page 352).
If it is not closed properly:
Close the fuel cap.
If it is closed properly:
Have the fuel system checked by an
authorized Mercedes-Benz Light Truck
Center.
Vehicles with diesel engine
only:
Your fuel tank is empty.After refueling start, turn off and
restart the engine three or four times in
succession.
The limp-home mode is canceled. You do
not need to have your vehicle checked.
lThe red distance warning lamp comes on
while driving and you hear a warning sound.You are gaining too rapidly on
the vehicle ahead of you.Apply the brakes immediately.
Carefully observe the traffic situation.
You may need to brake or maneuver to
avoid hitting an obstacle.
The Distronic* has recognized
a stationary obstacle on your
probable line of travel.

419 Practical hints
What to do if …
ProblemPossible cause/consequenceSuggested solution
vThe yellow ESP® warning lamp
comes on while the engine is
running.The ESP® has been switched off with the
ESP® switch or has switched off due to a
malfunction.
Risk of accident!
Adapt your speed and driving to the prevail-
ing road, weather, and traffic conditions.
Switch the ESP® back on (page 105).
Exceptions: (
page 104)
If the ESP
® cannot be switched back on:
Continue driving with added caution.
Observe additional messages in the
multifunction display that may appear.
Have the system checked at an autho-
rized Mercedes-Benz Light Truck
Center as soon as possible.
vThe yellow ESP® warning lamp
flashes while driving.The ESP® or the Electronic Traction System
has come into operation because of de-
tected traction loss of at least one tire.When driving off, apply as little throttle
as possible.
While driving, ease up on the accelera-
tor.
Adapt your speed and driving to the
prevailing road and weather condi-
tions.
Do not deactivate the ESP®.
Exceptions: (
page 104)
Failure to follow these instructions
increases the risk of an accident.