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454 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 key.There 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.
Key
Does Not Belong to VehicleThe SmartKey or SmartKey with
KEYLESS-GO* in the starter
switch does not belong to the
vehicle.Find the SmartKey or SmartKey with
KEYLESS-GO* that belongs to the vehicle
to operate the vehicle.
Change
Key BatteriesThe batteries in the SmartKey
with KEYLESS-GO* are dis-
charged.Replace the batteries (page 479).
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.
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455 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 a critical
number of LEDs 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 switch on
automatically.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
To switch off the headlamps
(U.S. vehicles only):
In the control system, set lamp operation
to manual mode (
page 144).
Switch off the headlamps using the
exterior lamp switch (
page 143).
Brake Lamp
LeftThe left brake lamp is malfunc-
tioning. A substitute bulb is
being used.Replace the bulb as soon as possible
(
page 480).
Brake Lamp
RightThe right brake lamp is malfunc-
tioning. A substitute bulb is
being used.Replace the bulb as soon as possible
(
page 480).
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456 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
.Cornering Lamp
LeftThe left corner-illuminating front
fog lamp is malfunctioning.Replace the bulb as soon as possible
(
page 480).
Cornering Lamp
RightThe right corner-illuminating
front fog lamp is malfunctioning.Replace the bulb as soon as possible
(
page 480).
Front Foglamp
LeftThe left front fog lamp is
malfunctioning.Replace the bulb as soon as possible
(
page 480).
Front Foglamp
RightThe right front fog lamp is
malfunctioning.Replace the bulb as soon as possible
(
page 480).
High Beam
LeftThe left high beam lamp is
malfunctioning.Halogen headlamp:
Replace the bulb as soon as possible
(
page 480).
Bi-Xenon* headlamp:
Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
High Beam
RightThe right high beam lamp is
malfunctioning.Halogen headlamp:
Replace the bulb as soon as possible
(
page 480).
Bi-Xenon* headlamp:
Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
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457 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
.License Plate Lamp
LeftThe left license plate lamp is
malfunctioning.Replace the bulb as soon as possible
(
page 480).
License Plate Lamp
RightThe right license plate lamp is
malfunctioning.Replace the bulb as soon as possible
(
page 480).
Low Beam
LeftThe left low beam lamp is
malfunctioning.Halogen headlamp:
Replace the bulb as soon as possible
(
page 480).
Bi-Xenon* headlamp:
Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
Low Beam
RightThe right low beam lamp is
malfunctioning.Halogen headlamp:
Replace the bulb as soon as possible
(
page 480).
Bi-Xenon* headlamp:
Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
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458 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
.Marker Lamp
Front LeftThe left front side marker lamp is
malfunctioning.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
Marker Lamp
Front RightThe right front side marker lamp
is malfunctioning.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
Parking Lamp
Front LeftThe front left parking lamp is
malfunctioning. A substitute
bulb is being used.Replace the bulb as soon as possible
(
page 480).
Parking Lamp
Front RightThe front right parking lamp is
malfunctioning. A substitute
bulb is being used.Replace the bulb as soon as possible
(
page 480).
Foglamp
Rear LeftThe left rear fog lamp is malfunc-
tioning.Replace the bulb as soon as possible
(
page 480).
Reverse Lamp
LeftThe left backup lamp is
malfunctioning.Replace the bulb as soon as possible
(
page 480).
Reverse Lamp
RightThe right backup lamp is
malfunctioning.Replace the bulb as soon as possible
(
page 480).
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459 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
. Switch Off LightsYou have removed the SmartKey
from the starter switch and
opened the driver’s door or
removed the SmartKey with
KEYLESS-GO* from the vehicle
and left the parking lamps or the
rear fog lamp on.Turn the exterior lamp switch toM
(
page 143).
Tail Lamp
LeftThe left tail lamp is malfunction-
ing. A substitute bulb is being
used.Replace the bulb as soon as possible
(
page 480).
Tail Lamp
RightThe right tail lamp is malfunc-
tioning. A substitute bulb is
being used.Replace the bulb as soon as possible
(
page 480).
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460 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
. Turn Signal
Rear LeftThe left rear turn signal lamp is
malfunctioning. A substitute
bulb is being used.Replace the bulb as soon as possible
(
page 480).
Turn Signal
Rear RightThe right rear turn signal lamp is
malfunctioning. A substitute
bulb is being used.Replace the bulb as soon as possible
(
page 480).
Turn Signal
Front LeftThe left front turn signal lamp is
malfunctioning. A substitute
bulb is being used.Replace the bulb as soon as possible
(
page 480).
Turn Signal
Front RightThe right front turn signal lamp is
malfunctioning. A substitute
bulb is being used.Replace the bulb as soon as possible
(
page 480).
Turn Signal
Left MirrorThe turn signal in the left exte-
rior rear view mirror is malfunc-
tioning. This message will only
appear if a critical number of
LEDs have stopped working.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
Turn Signal
Right MirrorThe turn signal in the right exte-
rior rear view mirror is malfunc-
tioning. This message will only
appear if a critical number of
LEDs have stopped working.Contact an authorized Mercedes-Benz
Light Truck Center as soon as possible.
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461 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
4Reserve FuelThe fuel level has gone below the reserve
mark.Refuel at the next gas station
(
page 352).
Ultra Low-sulfur
Diesel Fuel OnlyVehicles with diesel engine only:
The fuel level has gone below the reserve
mark.Refuel at the next gas station
(
page 352).
Only use commercially available
vehicular ULTRA-LOW SULFUR
HIGHWAY DIESEL FUEL
(15 ppm SULFUR MAXIMUM).
L Tele Aid
InoperativeOne or more main functions of the
Tele Aid* system are malfunctioning.Have the Tele Aid* system checked
by an authorized Mercedes-Benz Light
Truck Center.
Tele Aid
BatteryThe emergency power battery for the
Tele Aid* system is malfunctioning. If the
vehicle battery is also malfunctioning or
drained, Tele Aid* will not be operational.Have the Tele Aid* system checked
by an authorized Mercedes-Benz Light
Truck Center.
tFunction
unavailableThis display appears if
buttontorson the multifunc-
tion steering wheel is pressed and the
vehicle is not equipped with a telephone.
WTop Up
Washer FluidThe fluid level has dropped to
about1/3of total reservoir capacity.
Add washer fluid (page 362).