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380 Practical hints
What to do if …
Left displayRight displayPossible cause/consequencePossible solution
2 Brake WearThe brake pads have reached their
wear limit.Have the brake pads replaced as soon as pos-
sible.
Warning!G
Have brake pad replacement and other work
on the electro-hydraulic brake system
carried out by qualified technicians only.
Contact an authorized Mercedes-Benz
Center for further information.
The electro-hydraulic brake system must be
deactivated prior to working on the system.
High pressure is intermittently built up in the
system as part of its automatic self-test.
In addition, the system is automatically
activated when the vehicle is unlocked by
remote control, when the driver or passen-
ger door is opened, when the SmartKey in
the starter switch is turned to position1 or
the KEYLESS-GO* start/stop button is
pressed once, when the brake pedal
is depressed or when the parking brake is
released. Failure to deactivate the system
prior to maintenance will cause brake pis-
tons to extend and brake fluid to leak, which
may result in injuries (contusions and acid
burns). Extended brake pistons may also
cause injury.!Brake pad thickness must be visually
checked by a qualified technician at the intervals
specified in the Maintenance Booklet.
Page 387 of 489
386 Practical hints
What to do if …
Left displayRight displayPossible cause/consequencePossible solution
2You are attempting to drive with
one or more doors open.Close the doors.
Vehicles with KEYLESS-GO*:
You are pressing the lock button on
the door handle and at least one
door is open.
±Service
RequiredCertain electronic systems are
unable to relay information to the
control system. The following
systems may have failed:
Coolant temperature gauge
Tachometer
Have the electronic systems checked by an
authorized Mercedes-Benz Center
(
page 346).
_ Entry Position
Do Not DriveThe steering wheel has not yet
moved into its stored driving posi-
tion.Wait until the steering wheel has moved to its
driving position.
The message disappears.
Page 391 of 489
390 Practical hints
What to do if …
Left displayRight displayPossible cause/consequencePossible solution
KRetractable Roof
Not Opened/Closed
CompletelyThe retractable hardtop is not
locked properly.Stop the vehicle in a safe location. Observe
the traffic situation around you.
Push or pull on the retractable hardtop switch
until the indicator lamp in the switch goes out
and the retractable hardtop is completely
open or closed (
page 204).
OYou are driving with the hood open.Risk of accident!
Stop the vehicle in a safe location or as soon
as it is safe to do so.
Close the hood (page 283).
IRemove
KeyYou have forgotten to remove the
SmartKey from the starter switch.Remove the SmartKey from the starter
switch.
Replace
KeyThe SmartKey is no longer
functional.Contact an authorized Mercedes-Benz
Center.
FChange
Key BatteriesThe batteries in the SmartKey with
KEYLESS-GO* are discharged.Replace the batteries (page 407).
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391 Practical hints
What to do if …
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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 vehi-
cle.
There is strong radio-frequency
interference.
Stop the vehicle in a safe location or as soon
as it is safe to do so.
Search for the SmartKey with KEYLESS-GO*.
Otherwise the vehicle cannot be centrally
locked nor can the engine be started again af-
ter the engine is stopped.
Operate the vehicle with the SmartKey with
KEYLESS-GO* in the starter switch.
Key
Not DetectedThe SmartKey with KEYLESS-GO* is
not recognized when attempting to
start the engine with the
KEYLESS-GO start/stop button* on
the gear selector lever because:
The SmartKey with
KEYLESS-GO* is not in the vehi-
cle.
The battery in the SmartKey
with KEYLESS-GO* is not insert-
ed properly or completely dis-
charged.
Change the position of the SmartKey with
KEYLESS-GO* in the vehicle.
Make sure the batteries in the SmartKey with
KEYLESS-GO* are properly inserted
(
page 407) and are not discharged
(
page 113).
Start the engine with the SmartKey with
KEYLESS-GO* in the starter switch if
necessary.
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392 Practical hints
What to do if …
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FKey Detected
In VehicleA SmartKey with KEYLESS-GO* left
in the vehicle was recognized while
locking the vehicle from the out-
side.Take the SmartKey with KEYLESS-GO* out of
the vehicle.
.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 Center
as soon as possible.
AUTO Light
InoperativeThe light sensor is malfunctioning.
The headlamps switch on automati-
cally.Contact an authorized Mercedes-Benz 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 163).
Switch on headlamps using the exterior lamp
switch (
page 131).
Brake Lamp
Left
Auxiliary Bulb OnThe left brake lamp is malfunction-
ing. An auxiliary bulb has been
brought into use.Contact an authorized Mercedes-Benz Center
as soon as possible.
Brake Lamp
Right
Auxiliary Bulb OnThe right brake lamp is malfunction-
ing. An auxiliary bulb has been
brought into use.Contact an authorized Mercedes-Benz Center
as soon as possible.
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395 Practical hints
What to do if …
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.Tail Lamp
Right
Auxiliary Bulb OnThe right tail lamp is malfunction-
ing. An auxiliary bulb has been
brought into use.Contact an authorized Mercedes-Benz Center
as soon as possible.
Turn Signal
Left MirrorThe turn signal in the driver’s side
exterior rear view mirror is malfunc-
tioning. This message will only ap-
pear if all light emitting diodes have
stopped working.Contact an authorized Mercedes-Benz Center
as soon as possible.
Turn Signal
Right MirrorThe turn signal in the passenger
side exterior rear view mirror is mal-
functioning. This message will only
appear if all light emitting diodes
have stopped working.Contact an authorized Mercedes-Benz Center
as soon as possible.
Lights Are
still OnYou have removed the SmartKey
from the starter switch and opened
the driver’s door and left the head-
lamps on or removed the SmartKey
with KEYLESS-GO* from the vehicle
and left the headlamps on.Turn the exterior lamp switch toM
orU.
Turn Signal
Front Left
Auxiliary Bulb OnThe left front turn signal lamp is
malfunctioning. An auxiliary bulb
has been brought into use.Replace the bulb as soon as possible
(
page 409).
Page 404 of 489
403 Practical hints
Locking/unlocking in an emergency
Locking/unlocking in an emergency
Unlocking the vehicle
If you cannot unlock the vehicle using the
SmartKey or KEYLESS-GO*, unlock the
driver’s door and the trunk using the
mechanical key.
1Mechanical key locking tab
2Mechanical key
Move locking tab 1 direction of arrow
and slide the mechanical key 2 out of
the housing.Unlocking the driver’s door
Insert mechanical key 2 into the
driver’s door lock until it stops.
Turn mechanical key 2 counterclock-
wise to position 1.
The driver’s door is unlocked. You can
now open the driver’s door.
iUnlocking the vehicle with the mechanical
key and opening the driver’s door or the trunk
will trigger the anti-theft alarm system
(
page 98).
To cancel the alarm, insert the SmartKey or the
SmartKey with KEYLESS-GO* in the starter
switch.
1Unlocking
2Mechanical key
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404 Practical hints
Locking/unlocking in an emergency
Unlocking the trunk
A minimum height clearance of 6.2 ft
(1.89 m) is required to open the trunk lid.
Insert mechanical key 3 into the trunk
lid lock until it stops.
Turn mechanical key 3 counterclock-
wise to position 1.
The trunk is unlocked
Pull handle 2 and lift lid.
Turn mechanical key 3 back and
remove it from the trunk lid lock.
Unlocking the glove box
Lockable storage areas in the passenger
compartment include:
the glove box
the storage compartment under the
armrest
the rear storage compartments
If these cannot be unlocked by means of
the SmartKey or the SmartKey with
KEYLESS-GO*, use the mechanical key to
unlock the glove box.
Slide mechanical key 2 out of
SmartKey housing (
page 403).
Insert mechanical key 2 into the glove
box lock and turn it counterclockwise
to position1.
You can now open the glove box.
1Unlocking
2Handle
3Mechanical key
iTo unlock the remaining storage compart-
ments, the cause for the malfunction of the
SmartKey or the SmartKey with KEYLESS-GO*
must be determined and corrected, see
(
page 105) and (page 109).
1Separately unlocking the glove box
2Mechanical key