Page 36 of 506

34 Getting startedUnlockingSmartKeyStarter switch0For removing SmartKey
1Power supply to some electrical con-
sumers, such as seat adjustment
2Ignition (power supply for all electrical
consumers) and driving position.
All lamps (except low beam headlamp
indicator lamp, high beam headlamp in-
dicator lamp, and turn signal indicator
lamps unless activated) in the instru-
ment cluster come on. If a lamp in the
instrument cluster fails to come on
when the ignition is switched on, have
it checked and replaced if necessary. If
a lamp in the instrument cluster re-mains on after starting the engine or
comes on while driving, refer to “Lamps
in instrument cluster” (
page 356).
3Starting position
For information on starting the engine us-
ing the SmartKey, see “Starting with the
SmartKey” (
page 46).
iWhen you switch on the ignition, the in-
dicator and warning lamps (except low
beam headlamp indicator lamp, high
beam headlamp indicator lamp, and
turn signal indicator lamps unless acti-
vated) in the instrument cluster come
on. This indicates that the respective
systems are operational. The indicator
and warning lamps (except low beam
headlamp indicator lamp, high beam
headlamp indicator lamp, and turn sig-
nal indicator lamps if activated) should
go out when the engine is running.iThe SmartKey can only be removed
from the starter switch with the gear
selector lever in position P.
!If the SmartKey can still not be turned,
the battery may not be sufficiently
charged.
Check the battery and charge it if
necessary (
page 435).
Get a jump start (
page 436).
To prevent accelerated battery dis-
charge or a completely discharged bat-
tery, always remove the SmartKey from
the starter switch when the engine is
not in operation.
Page 37 of 506

35 Getting started
Unlocking
SmartKey with KEYLESS-GO*
Pressing the KEYLESS-GO start/stop but-
ton on the gear selector lever corresponds
to turning the SmartKey to the various
starter switch positions.
If you firmly depress the brake pedal dur-
ing pressing KEYLESS-GO start/stop but-
ton, the engine starts automatically.
KEYLESS-GO start/stop button1USA only
2Canada only
The SmartKey with KEYLESS-GO must be
located in the vehicle.
Make sure the gear selector lever is set
toP.
Do not depress the brake pedal.
Position 0
Before you press the KEYLESS-GO start/
stop button, the vehicle's on-board elec-
tronics have status 0 (as with SmartKey re-
moved).Position 1
Press KEYLESS-GO start/stop button
once.
This supplies power to some electrical
consumers, such as seat adjustment.
iThe function of the SmartKey overrules
the KEYLESS-GO function.
iIf you now press the KEYLESS-GO
start/stop button
once again, the ignition (position2)
is switched on.
twice, the power supply is again
switched off.
Page 38 of 506

36 Getting startedUnlockingIgnition (or position 2)
Press KEYLESS-GO start/stop button
twice.
This supplies power to all electrical
consumers. All lamps (except low
beam headlamp indicator lamp, high
beam headlamp indicator lamp, and
turn signal indicator lamps unless acti-
vated) in the instrument cluster come
on. If a lamp in the instrument cluster
fails to come on when the ignition is
switched on, have it checked and re-
placed if necessary. If a lamp in the in-
strument cluster remains on after
starting the engine or comes on while
driving, see “Lamps in instrument clus-
ter” (
page 356).For information on starting the engine us-
ing the KEYLESS-GO start/stop button,
see “Starting with KEYLESS-GO*”
(
page 47).
iIf you now press the KEYLESS-GO
start/stop button once, the power sup-
ply is again switched off.
iWhen you switch on the ignition, the in-
dicator and warning lamps (except low
beam headlamp indicator lamp, high
beam headlamp indicator lamp, and
turn signal indicator lamps unless acti-
vated) in the instrument cluster come
on. This indicates that the respective
systems are operational. The indicator
and warning lamps (except low beam
headlamp indicator lamp, high beam
headlamp indicator lamp, and turn sig-
nal indicator lamps if activated) should
go out when the engine is running.
Page 130 of 506

128 Controls in detailSeats1Seat heating switch
Switch on the ignition (
page 33).
Switching seat heating on
Press button1 repeatedly until the
desired heating level is set.
One or more red indicator lamps on the
switch show the selected heater level.Switching seat heating off
Press button1 repeatedly until all in-
dicator lamps go out.
Seat ventilation*
The switch is located on the center con-
sole. Seat ventilation can be activated
manually with the ignition on, or by the
summer opening feature (
page 220).
The blue indicator lamps on the switch
show the ventilation level selected:
iThe seat heating will be automatically
switched off after approximately
20 minutes.!If one or more of the lamps on the seat
heater switch are flashing, there is in-
sufficient voltage available since too
many electrical consumers are turned
on. The seat heater switches off auto-
matically.
The seat heater will switch back on
again automatically as soon as suffi-
cient voltage is available.
Level3
Three indicator lamps on
2
Two indicator lamps on
1
One indicator lamp on
off
No indicator lamp on
Page 131 of 506
129 Controls in detailSeats
1Seat ventilation switch
Switch on the ignition (
page 33).Switching seat ventilation on
Press button1 repeatedly until the
desired ventilation level is set.
Switching seat ventilation off
Press button1 repeatedly until all in-
dicator lamps go out.iThe seat ventilation is automatically set
to the highest level if activated via sum-
mer opening feature (
page 220).
!If one or all of the lamps flash on the
seat ventilation switch, there is insuffi-
cient voltage due to too many electrical
consumers being switched on. The seat
ventilation switches off automatically.
The seat ventilation will switch back on
again automatically as soon as suffi-
cient voltage is available.
Page 193 of 506

191 Controls in detail
Good visibility
Rear window defroster
The rear window defroster uses a large
amount of power. To keep the battery
drain to a minimum, switch off the defrost-
er as soon as the rear window is clear. The
defroster is automatically deactivated af-
ter approximately 6 to 17 minutes of oper-
ation depending on the outside
temperature.
Activating
Press buttonF (
page 194) or
(
page 195) or button1
(page 206) or (
page 207) on the
respective climate control panel.
The indicator lamp on the button
comes on.Deactivating
Press buttonF or button1
again.
The indicator lamp on the button goes
out.Warning!
G
Any accumulation of snow and ice should be
removed from the rear window before driv-
ing. Visibility could otherwise be impaired,
endangering you and others.
!If the rear window defroster switches
off too soon and the indicator lamp
starts flashing, this means that too
many electrical consumers are operat-
ing simultaneously and there is insuffi-
cient voltage in the battery. The system
responds automatically by deactivating
the rear window defroster.
As soon as the battery has sufficient
voltage, the rear window defroster au-
tomatically turns itself back on.
Page 311 of 506

309 Operation
Engine compartment
Replace and tighten cap.
For more information on coolant, see the
“Technical data” section (
page 466).
Battery
Your vehicle is equipped with two batter-
ies:
Auxiliary battery (located in the engine
compartment).
Main battery (starter and electrical
consumers; located in the trunk).
These batteries should always be suffi-
ciently charged in order to achieve their
rated service life. Refer to Maintenance
Booklet for battery maintenance intervals.
If you use your vehicle mostly for short-dis-
tance trips, you will need to have the bat-
tery charge checked more frequently.When replacing batteries, always use bat-
teries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Center about
steps you need to observe.
Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
G
Observe all safety instructions
and precautions when handling
automotive batteries.
A
Risk of explosion.
D
Keep flames or sparks away
from battery. Do not smoke.
B
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
In case it does, immediately
flush affected area with clear
water and seek medical help if
necessary.
E
Wear eye protection.
C
Keep children away.
F
Follow the instructions in this
Operator's Manual.
Page 358 of 506

356 Practical hintsWhat to do if …Lamps in instrument clusterGeneral information:
If any of the following lamps in the instru-
ment cluster fails to come on during thebulb self-check when switching on the igni-
tion, have the respective bulb checked and
replaced if necessary.Problem
Possible cause
Suggested solution
-
The yellow ABS malfunction indi-
cator lamp comes on while driv-
ing.
The ABS has detected a malfunction and has
switched off. The BAS and the ESP are also
switched off (see messages in display).
The SBC brake system is still functioning nor-
mally but without the ABS available.
If the ABS control unit is malfunctioning, oth-
er systems such as the Parktronic system*,
Distronic*, or the automatic transmission
may also be malfunctioning.
Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability.
Read and observe messages in the
display (
page 367).
Have the system checked at an autho-
rized Mercedes-Benz Center as soon
as possible.
Failure to follow these instructions in-
creases the risk of an accident.
The charging voltage has fallen below
10 volts. The ABS has switched off.
The battery may not be sufficiently charged.
Switch off electrical consumers that
are currently not needed, e.g. seat
heating.
If necessary, have the generator and
battery checked.
When the voltage is above this value
again, the ABS is operational again.