2008 MERCEDES-BENZ R320 warning

441 Practical hints
What to do if …
Display messagePossible
cause/consequencePossible solution
Monitor the 59indicator lamp on the center console (page 81) and
the multifunction display in the instrument cluster (
page 29) for the following:
With the seat unoccupied and the ignition turned on,

the 59indicator lamp on the center console should illuminate and
remain illuminated, indicating that the OCS (
page 77) has deactivated the air
bag.

the message Front Passenger Airbag Enabled See Operator’s Manual or the
message
Front Passenger Airbag Disabled See Operator’s Manual should
not appear in the multifunction display at any time the seat is unoccupied. Wait
at least 60 seconds for the system to complete the necessary check cycles and
to make sure neither message appears in the multifunction display.
If above conditions are met, you can occupy the front passenger seat again.
Depending on the front passenger classification sensed by the OCS (
page 77),
the 59indicator lamp will remain illuminated or go out.
If above conditions are not met, the system is not working properly. Have the
system checked as soon as possible by an authorized Mercedes-Benz Light Truck
Center.
Warning!G
If the 59indicator lamp re-
mains out even after performing the above
corrective steps, do not have any children
12 years old and under and other small individuals use the front passenger seat
until the system has been repaired.

442 Practical hints
What to do if …
Display messagePossible cause/consequencePossible solution
Check tires,
then restart
Run Flat Indicator.
There was a warning message about
a loss in the tire inflation pressure
and the Run Flat Indicator has not
been reactivated yet.Make sure that the correct tire inflation pressure is set
for each tire.
Then restart the Run Flat Indicator (page 375).
Run Flat Indicator
InoperativeRun Flat Indicator is malfunctioning.Have the Run Flat Indicator checked by an authorized
Mercedes-Benz Light Truck Center.
Tire Pressure
Check TiresThe Run Flat Indicator indicates that
the pressure is too low in one or more
tires.Carefully bring the vehicle to a halt, avoiding abrupt
steering and braking maneuvers. Observe the traffic
situation around you.
Check and adjust tire inflation pressure as required
(
page 373).
If necessary, replace the wheel (page 492).
Restart the Run Flat Indicator after adjusting the tire
inflation pressure values (
page 375).
Tire pressure
displayed after
driving for
a few minutes
.
Vehicles with Advanced TPMS*:
The tire inflation pressure is being
checked.Drive the vehicle for a few minutes.

447 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
;(USA only)
3(Canada only)
Check
Brake Fluid LevelThere is insufficient brake fluid
in the reservoir.Risk of accident! Carefully stop the vehi-
cle 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 message Check Brake
Fluid Level
displayed can result in an ac-
cident. Have your brake system checked im-
mediately. Do not add brake fluid before
checking the brake system. Overfilling the
brake fluid reservoir can result in spilling
brake fluid on hot engine parts and the
brake fluid catching fire. You could 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.

449 Practical hints
What to do if …
During severe operation conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display symbolDisplay messagePossible cause/consequencePossible solution
Observe the coolant temperature in the
multifunction display (
page 164).
If the temperature rises again:
Contact an authorized
Mercedes-Benz Light Truck Center
immediately.
Warning!G

Driving when your engine is overheated
can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously
burned.

Steam from an overheated engine can
cause serious burns and can occur just
by opening the engine hood. Stay away
from the engine if you see or hear steam
coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.
!The engine should not be operated with the
coolant temperature above 248°F (120°C).
Doing so may cause serious damage which is
not covered by the Mercedes-Benz Limited
Warranty.

450 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
B Top Up Coolant
See Operator’s ManualThe coolant level is too low.Add coolant (page 360).
If you have to add coolant frequently,
have the cooling system checked by an
authorized Mercedes-Benz Light Truck
Center.
Warning!G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You could be seriously burned.
!Do not ignore the low engine coolant level
warning. Extended driving with the message and
symbol displayed may cause serious engine
damage not covered by the Mercedes-Benz
Limited Warranty.
Do not drive without sufficient amount of coolant
in the cooling system. The engine will overheat,
causing major engine damage.

451 Practical hints
What to do if …
When the message Check engine oil
level at next refueling.
appears while
the engine is running and at operating tem-
perature, the engine oil level has dropped
to approximately the minimum level.
When this occurs, the warning will first
come on intermittently and then stay on if
the oil level drops further.Visually check for oil leaks. If no obvious oil
leaks are noted, drive to the nearest
service station where the engine oil should
be topped to the required level with an
approved engine oil.
For information on approved engine oils,
refer to the Factory Approved Service
Products pamphlet (USA only) or contact
an authorized Mercedes-Benz Light Truck
Center.
Display symbolDisplay messagePossible cause/consequencePossible solution
NCheck engine oil level
at next refueling.The engine oil level is too low.Check the engine oil level (page 358).
!The engine oil level warning should not be
ignored. Extended driving with the symbol
displayed could result in serious engine damage
that is not covered by the Mercedes-Benz
Limited Warranty.

462 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
HTire Pressure(s)
Please CorrectVehicles with Advanced TPMS*:
The tire pressure is too low in one
or more tires.Check and correct tire inflation pressure as
required (
page 373).
Tire Pressure
Caution - Tire DefectOne or more tires are deflating.Carefully bring the vehicle to a halt, avoiding
abrupt steering and braking maneuvers.
If necessary, change the wheel (page 492).
Caution: Tire DefectOne or more tires are deflating.
Vehicles with Advanced TPMS*:
The respective tire is indicated in
the multifunction display.Carefully bring the vehicle to a halt, avoiding
abrupt steering and braking maneuvers.
If necessary, change the wheel (page 492).
Warning!G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
may lose control of the vehicle. Continued
driving with a flat tire will cause excessive
heat build-up and possibly a fire.

463 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
HTire Pressure
Check TiresThe tire pressure in one or more tires is
already below the minimum value.Carefully bring the vehicle to a halt, avoid-
ing abrupt steering and braking maneuvers.
Check and adjust tire pressure as required
(
page 373).
If necessary, change the wheel
(
page 492).
Check TiresThe tire pressure in one or more tires is
already below the minimum value.
Vehicles with Advanced TPMS*:
The respective tire is indicated in the
multifunction display.Carefully bring the vehicle to a halt, avoid-
ing abrupt steering and braking maneuvers.
Check and adjust tire pressure as required
(
page 373).
If necessary, change the wheel
(
page 492).
Warning!G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
may lose control of the vehicle. Continued
driving with a flat tire will cause excessive
heat build-up and possibly a fire.