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474 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 messagesPossible cause/consequencePossible solution
Observe the coolant temperature in the
multifunction display (
page 164).
If the temperature raises 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 which can occur just by open-
ing the engine hood. Stay away from the en-
gine 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.
Page 476 of 595
475 Practical hints
What to do if …
Display symbolDisplay messagesPossible cause/consequencePossible solution
B Top up Coolant
See Oper. ManualThe coolant level is too low.Add coolant (page 382).
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.
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476 Practical hints
What to do if …
When the message Add 1 qt. engine oil
at 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.
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 messagesPossible cause/consequencePossible solution
NCheck eng. oil level
at next refuelingThe engine oil level is too low.Check the engine oil level (page 381).
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 382) and check
the engine oil level (
page 381).
Engine oil level
cannot be measuredThe measuring system is
malfunctioning.Have the measuring system checked by
an authorized Mercedes-Benz Light Truck
Center.
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477 Practical hints
What to do if …
Display symbolDisplay messagesPossible cause/conse-
quencePossible 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 382) and check the en-
gine oil level (
page 381).
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 (gaso-
line engine) 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 381) and add
oil as required (
page 382).
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 in serious engine damagethat is not covered by the Mercedes-Benz
Limited Warranty.
Page 479 of 595
478 Practical hints
What to do if …
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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 door(s).
AGas 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 375).
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 380) 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).
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479 Practical hints
What to do if …
Display symbolDisplay messagesPossible cause/consequencePossible solution
FKey
not detectedThe SmartKey with
KEYLESS-GO* is not recognized
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 in a safe location or as
soon as it is safe to do so.
Apply the parking brake (page 68).
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 recognized.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 recognized
while the ignition is switched on
(
page 41) 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.
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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*.Visit 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 506).
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 the SmartKey in the starter switch
(
page 42).
or
Take the SmartKey with KEYLESS-GO*
with you when leaving the vehicle.
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481 Practical hints
What to do if …
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. 3rd brake lampThe high mounted brake lamp is
malfunctioning. This message
will only appear if a critical num-
ber of LEDs have stopped work-
ing.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
Active headlamps
inoperativeThe active Bi-Xenon* headlamps
system is malfunctioning.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 515).
Brake lamp
RightThe right brake lamp is malfunc-
tioning. A substitute bulb is
being used.Replace the bulb as soon as possible
(
page 515).
Display malfunction
Visit workshopThe display for the lamps or the
system is malfunctioning.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
Front foglamp
LeftThe left front fog lamp is
malfunctioning.Replace the bulb as soon as possible
(
page 514).
Front foglamp
RightThe right front fog lamp is
malfunctioning.Replace the bulb as soon as possible
(
page 514).