2007 MERCEDES-BENZ R350 Owner's Manual

456 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 166).
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.

457 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
B Top up coolant
See Oper. ManualThe coolant level is too low.Add coolant (page 370).
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.

458 Practical hints
What to do if …
When the message Add 1 qt. engine oil
when next refueling
(Canada: 1 liter)
appears while the engine is running and at
operating temperature, the engine oil level
has dropped to approximately the mini-
mum 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 oil specified in the Factory
Approved Service Products pamphlet.
Display symbolDisplay messagePossible cause/consequencePossible solution
NCheck eng. oil level
at next refuelingThe engine oil level is too low.Check the engine oil level (page 366).
USA only:
Add 1 qt. engine oil
at next refueling
Canada only:
Add 1 liter engine oil
at next refueling
The engine oil level is too low.Add engine oil (page 369) and check
the engine oil level (
page 366).
Engine oil level
cannot be measuredThe measuring system is
malfunctioning.Have the measuring system checked by
an authorized Mercedes-Benz Light Truck
Center.

459 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
NEngine oil level
Stop car, turn engine offThere is no oil in the engine.
There is a danger of engine
damage.Carefully bring the vehicle to a halt as
soon as it is safe to do so in a safe
location.
Turn off the engine.
Add engine oil (page 369) and check
the engine oil level (
page 366).
Engine oil level
Reduce oil levelYou have added too much
engine oil. There is a risk of
damaging the engine and/or the
catalytic converter (gasoline en-
gine) or the oxidation catalyst
(diesel engine).Have oil siphoned or drained off.
Observe all legal requirements with
respect to its disposal.
Engine oil level
Visit workshopThe engine oil has dropped to a
critical level.Check the engine oil level (page 366)
and add oil as required (
page 369).
If you must add engine oil frequently, have
the engine checked for possible leaks.
!The engine oil level warnings should not be
ignored. Extended driving with the symbol dis-
played could result inserious engine damage that is not covered by the
Mercedes-Benz Limited Warranty.

460 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
c You are driving with one or more
doors open.Stop the vehicle in a safe location or as
soon as it is safe to do so.
Close the doors.
A Gas cap is openA 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 360).
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.
aYou are driving with the hood or
the tailgate open.Carefully bring the vehicle to a halt as
soon as it is safe to do so in a safe
location.
Close the hood (page 364) or the
tailgate (
page 125).
You are trying to lock the vehicle
with the KEYLESS-GO* function
with a door or the tailgate open.Close all doors and/or the tailgate
(
page 125).

461 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
FKey
not detectedThe SmartKey with
KEYLESS-GO* is not detected
while the engine is running
because

the SmartKey with
KEYLESS-GO* is not in the
vehicle

there is strong
radio-frequency interference
Stop the vehicle as soon as it is safe to do
so.
Apply the parking brake (page 66).
Search for the SmartKey with
KEYLESS-GO*.
Otherwise the vehicle cannot be centrally
locked nor can the engine be started
again after the engine is stopped.
The SmartKey with
KEYLESS-GO* is momentarily
not detected.Change the position of the SmartKey with
KEYLESS-GO* in the vehicle.
Operate the vehicle with the SmartKey in
the starter switch if necessary.
Key
not detectedThe SmartKey with
KEYLESS-GO* is not detected
while the ignition is switched on
(
page 39) and a door is
opened or closed and the
SmartKey with KEYLESS-GO* is
not in the vehicle.
Search for the SmartKey with
KEYLESS-GO*.
Otherwise the vehicle cannot be locked
nor can the engine be started.
Change the position of the SmartKey with
KEYLESS-GO* in the vehicle.

462 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
FKey detected
in vehicleA SmartKey with KEYLESS-GO*
left in the vehicle was detected
while trying to lock the vehicle
from the outside.Take the SmartKey with KEYLESS-GO*
out of the vehicle.
Remove keyYou have forgotten to remove
the SmartKey.Remove the SmartKey from the starter
switch.
You need a new keyThere is no additional code avail-
able for SmartKey or SmartKey
with KEYLESS-GO*.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
Change
key batteriesThe batteries in the SmartKey
with KEYLESS-GO* are dis-
charged.Replace the batteries (page 483).
Don’t forget
your keyThis message appears for a
maximum of 60 seconds if the
driver’s door is opened with the
engine shut off and no SmartKey
in the starter switch.
This message is only a reminder.Insert SmartKey in the starter switch.
or
Take the SmartKey with KEYLESS-GO*
with you when leaving the vehicle.

463 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
. 3rd brake lampThe high mounted brake lamp is
malfunctioning. This message
will only appear if all light
emitting diodes have stopped
working.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
Active headlamps
inoperativeThe active Bi-Xenon* headlamp
system is malfunctioning.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
AUTO Light
inoperativeThe light sensor is malfunction-
ing. The headlamps do not
switch on automatically.In the control system, set lamp operation
to manual mode (
page 147).
Switch on headlamps using the exterior
lamp switch (
page 146).
Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
Brake lamp leftThe left brake lamp is malfunc-
tioning. A substitute bulb is
being used.Replace the bulb as soon as possible
(
page 484).
Brake lamp rightThe right brake lamp is malfunc-
tioning. A substitute bulb is
being used.Replace the bulb as soon as possible
(
page 484).