Page 392 of 473

391 Practical hints
Replacing SmartKey batteries
Replacing SmartKey batteries
If the batteries in the SmartKey are
discharged, the vehicle can no longer be
locked or unlocked. It is recommended
to have the batteries replaced at an autho-
rized Mercedes-Benz Center.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.SmartKey
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove the mechanical key from the
SmartKey (
page 387).
1Mechanical key
2Battery compartment
Insert mechanical key1 into opening.
Press mechanical key1 in direction of
arrow.
Battery compartment2 is unlatched.
Pull battery compartment2 out of the
housing.
Warning!G
Batteries contain poisonous and corrosive
substances. Therefore keep the batteries
out of reach of children.
If a battery is swallowed, seek medical help
immediately.
iWhen inserting the batteries, make sure
they are clean and free of lint.
iWhen replacing batteries, always replace
both batteries.
The required replacement batteries are available
at any Mercedes-Benz Center.
Page 393 of 473
392 Practical hints
Replacing SmartKey batteries
3Batteries
4Contact springs
Pull out batteries 3.
Using a lint-free cloth, insert new
batteries3 under contact springs4
with the positive terminal (+) side
facing up.
Return battery compartment2
(
page 391) into the housing until it
locks into place.
Slide the mechanical key back into the
SmartKey.
Check the operation of the SmartKey.
Page 416 of 473

415 Practical hints
Battery
Battery
The battery is located in the engine com-
partment on the right-hand side below the
water tray (
page 416).
1Battery
2Positive terminal
3Negative terminal
Warning!G
Failure to follow these instructions can re-
sult in severe injury or death.
Observe all safety instructions and precau-
tions when handling automotive batteries
(
page 303).
Never lean over batteries while connecting
them, as you could otherwise be injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come into contact with
eyes, skin or clothing. In case it does, imme-
diately flush affected area with water and
seek medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
Warning!G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof batteries only to avoid the
risk of acid burns in the event of an
accident.
!Never loosen or detach battery terminal
clamps while the engine is running or the
SmartKey is in the starter switch. Otherwise the
alternator and other electronic components
could be severely damaged.
Have the battery checked regularly by an
authorized Mercedes-Benz Center.
Refer to Maintenance Booklet for maintenance
intervals or contact an authorized
Mercedes-Benz Center for further information.
Page 417 of 473

416 Practical hints
Battery
Disconnecting the battery
1Water tray
2Lock
Apply the parking brake (page 59).
Make sure the gear selector lever* is
set to positionP (manual transmission
to Neutral).
Turn off all electrical consumers.
Remove the SmartKey from the starter
switch.
Open the hood (page 294).
Turn locks2 one quarter turn.
Remove water tray1.
Read and observe safety instructions
and precautions (
page 303) and
(
page 415).
Use a 10 mm open-end wrench to dis-
connect the negative lead from battery
negative terminal3 (
page 415).
Remove the cover from battery positive
terminal 2 (
page 415).
Use a 10 mm open-end wrench to dis-
connect the positive lead from battery
positive terminal2 (
page 415).
Warning!G
With a disconnected battery
you will no longer be able to turn the
SmartKey in the starter switch
automatic transmission*: the gear se-
lector lever will remain locked in
positionP
!Always disconnect the battery in the order
described below. Otherwise the vehicle’s
electronics can be damaged.
Page 423 of 473

422 Practical hints
Towing the vehicle
Installing towing eye bolt
The towing eye bolt is supplied with the ve-
hicle tool kit, located in the compartment
underneath the trunk floor (
page 382).
The towing eyes are located on the passen-
ger side in the front and rear bumper.
Take vehicle tool kit out of trunk
(
page 382).
Front cover
1Cover in front bumper
!Towing of the vehicle should only be done
using the properly installed towing eye bolt.
Never attach a tow cable, tow rope or tow rod to
the vehicle chassis, frame or suspension parts.
iWhen towing the vehicle with all wheels on
the ground, please note the following:
With the automatic central locking activated and
the SmartKey in starter switch position2, the
vehicle doors lock if the left front wheel as well
as the right rear wheel are turning at vehicle
speeds of approximately 9 mph (15 km/h) or
more.
To prevent the vehicle door locks from locking,
deactivate the automatic central locking
(
page 102).
iTo signal turns while being towed with the
hazard warning flasher in use, switch on ignition
and activate the combination switch for the left
or right turn signal in the usual manner – only the
selected turn signal will operate.
Upon canceling the turn signal, the hazard warn-
ing flasher will operate again.
iThe gear selector lever* will remain locked
in positionP (vehicles with automatic transmis-
sion*) and the SmartKey will not turn in the
starter switch if the battery is disconnected or
discharged. For more information, see “Battery”
(
page 415) or “Jump starting” (page 419).
Vehicles with automatic transmission*:
For information on manual unlocking of gear
selector lever, see (
page 389).
Page 453 of 473

452 Index
Deactivating 185
Defrosting 170, 188
Residual heat utilization 192
Sun sensor 25
Temperature 186
Automatic shift program 161
Automatic transmission*
Accelerator position 159
Automatic shift program 161
Automatic transmission fluid
(ATF) 300
Driving 53
Emergency operation (limp-home
mode) 167
Fluid level 300
Gear ranges 160
Gear selector lever 155
Gear selector lever
(Unlocking manually) 389Gear selector lever control one-touch
gearshifting 162
Gear selector lever positions 157
Gear shifting malfunctions 167
Gearshift pattern 52
Kickdown 159
Kickdown, manual shift
program* 167
Manual shift program* 165
Program mode selector switch 161
Shifting procedure 156
Steering wheel gearshift control
one-touch gearshifting* 163
B
Backup lamp
Messages in the multifunction
display 377
Replacing bulbs 395Bar 328
BAS 86
Batteries (SmartKey)
Replacing 391
Battery (Vehicle) 303, 415
Charging 417
Jump starting 419
Messages in the multifunction
display 366
Bead 328
Bi-Xenon headlamps* 394
Brake Assist System see BAS
Brakes 280
Brake fluid 292, 446
Messages in the multifunction
display 367
SLK 55 AMG 281
Warning lamp 348
Break-in period 278
Bulbs
Messages in the multifunction
display 375–380
Replacing 393
Page 459 of 473

458 Index
H
Hard plastic trim items, cleaning 342
Hazard warning flasher 115, 116
Head restraint height (Seats) 42
Headlamps
Bi-Xenon* 394
Cleaning system* 168, 302, 450
Night security illumination (Control
system) 144
Switching off 61
Switching on 55
Headliner, cleaning 342
Head-thorax air bag 70
Heating
Seats* 104
Steering wheel* 276
High beam
Flasher 113
Headlamps 55, 113
Headlamps, bulbs 394
High beam headlamps 109
High mounted brake lamp 395
High-performance brake system 281
Hood 294
Horn 25
Hydroplaning 284I
Identification labels see Labels
Ignition (Position in starter switch) 37
Immobilizer see Anti-theft systems
Infant and child restraint systems see
Children in the vehicle
Instrument cluster 27, 118
Clock 120
Lamps, indicator and warning 346
Overview 26
Instruments and controls see Cockpit
Interior rear view mirror see Mirrors
Intermittent/interval wiping see
Windshield wipers
J
Jack (Vehicle tool kit) 382
Lifting vehicle 407
Lowering vehicle 413
Jump starting 419K
Kickdown 159
Kilopascal 328
Knee bag see Air bags
L
Labels 430
Lamp in center console 354
Lamps in instrument cluster 346
Lamps, indicator and warning
ABS 346, 347
Battery (SmartKey) 97
Brakes 348
CHECK ENGINE 349
ESP
®87, 350
Passenger front air bag off 74, 354
Fuel reserve 353
Passenger front air bag off 354
Seat belts 351–352
SRS 65, 353
Page 461 of 473

460 Index
Manual transmission 153
Driving 53
Gearshift pattern 51
Starting with SmartKey 51
Maximum inflation pressure 329
Maximum load rating 328
Maximum loaded vehicle weight 328
Mechanical key see SmartKey
Memory function* 107
Menus see Control system menus
Messages in the multifunction display see
Multifunction display messages
Mirror lamp* see Sun visors
Mirrors 168
Additional turn signals 394
Adjusting 46
Antiglare position 168
Auto-dimming* 169
Exterior rear view mirrors 46
Interior rear view mirror 46Mobile phone see Telephone*
MOE tires* see MOExtended system*
MOExtended system* 317, 414
MON 292, 447
Motor Octane Number see MON
MP3 210
Multifunction display 121
Multifunction display messages 356
ABS 358
Air bags 361–364
Battery, Vehicle 366
Brake fluid 367
Brakes 367
Bulbs 375–380
Coolant 368–370
Cruise control 358
Doors 371
Engine oil 372–373
ESP
®358, 359Passenger front air bag 363
Fuel 374
Hood 375
Maintenance service indicator 334
Parking brake 366
Retractable hardtop 374, 381
Run Flat Indicator* 365
Seat belt 381
SmartKey 375
SRS 360
Symbol messages 366
Telephone* 381
Text messages 358
Transmission 360
Trunk lid 381
Vehicle status message memory 135
Washer fluid 381
Multifunction steering wheel 28, 122
Heating* 276