363 Electronic main key
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index Changing batteries in the electronic main key
1Transmit buttons
2Lamp for battery check and function control
Checking batteries
If one of the transmit buttons (1) is pressed, the battery
check lamp (2) lights up briefly – indicating that the
batteries are in order.
Change batteries if the battery check lamp (2) does not
light up briefly.Changing batteries
Move locking tab (3) in direction of right arrow and
remove mechanical key (4, left arrow).
P80.20-2201-26
1
2
P80.35-2029-26
4
3
364 Electronic main key
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Insert mechanical key (4) in side opening (5) to open
latch. Press briefly (do not use mechanical key as lever)
to release battery compartment.
Remove mechanical key from side opening.
Carefully remove battery compartment in direction of
arrow (6).Change batteries (7), inserting new ones under contact
spring (8) with plus (+) side facing up.
Return battery compartment into housing until locked
in place and slide mechanical key back into electronic
main key.
P80.35-2025-26
5
4
6
P80.35-2027-26
78
365 Electronic main key
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index Important!
Batteries contain materials that can harm the
environment if disposed of improperly. Recycling of
batteries is the preferred method of disposal. For
disposal, please follow manufacturer’s recommendation
on battery package.
Replacement Battery:
Lithium, type CR 2025 or equivalent.Synchronizing remote control
The remote control may have to be resynchronized, if
the vehicle cannot be locked or unlocked.
To synchronize insert electronic key in starter switch.
The remote control should once again be operational.
367 KEYLESS-GO-card
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index Changing batteries
Pry open cover (1) (e.g. by using a narrow blade screw
driver) and remove batteries.
Install new batteries as indicated by the “+” and “-”
markings in the KEYLESS-GO-card.Important!
Batteries contain materials that can harm the
environment if disposed of improperly. Recycling of
batteries is the preferred method of disposal. For
disposal, please follow manufacturer’s recommendation
on battery package.
Replacement batteries:
Lithium, type CR 2025 or equivalent.
368 Emergency engine shut-down
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Emergency engine shut-down
If the engine can no longer be stopped using the
electronic key or the start-/stop button (vehicles with
KEYLESS-GO), the engine can be turned off by
withdrawing two fuses.
For easy removal of fuses use the fuse extractor
(supplied with vehicle tool kit) to pull out the fuses
marked on the fuse chart as “ENGINE EMERGENCY
OFF”.
The fuse chart is also located in the vehicle tool kit,
see page 335.
For fuses see page 325.Fuel filler flap, manual release
Remove the battery cover (see page 346) and the trim
inside the trunk on the right-hand side. Pull the release
knob (arrow) and open the fuel filler f lap.
402 Index
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car careIndex
Residual engine heat utilization ............................ 174
Special settings ......................................................... 169
Switching on and off ................................................ 175
Windows fogged on the inside ................................ 170
Windows fogged on the outside .............................. 171
Automatic transmission ...............................................229
Emergency operation ...............................................237
Fluid level ...................................................................332
Program mode selector switch ...............................236
Selector lever position ..............................................232
BBabySmart
TM airbag deactivation system ..................... 88
Self-test ......................................................................... 89
Backrest ............................................................................. 72
BAS (Brake assist system) ............................................268
Battery .............................................................................346
Battery recycling .......................................................348
BATTERY/ALTERNATOR -
malfunction and warning messages ......................299
Block heater ....................................................................249
BRAKE ASSIST - malfunction
and warning messages ............................................300
Brake assist system (BAS) ............................................268Brake fluid ...........................................240, 292, 393, 395
BRAKE FLUID -
malfunction and warning messages ......................301
BRAKE LINING WEAR -
malfunction and warning messages ......................301
Brake pad wear ...............................................................301
Brake warning lamp ..................................................... 292
Brake fluid low ......................................................... 292
Brakes ...................................................238, 240, 268, 272
CCapacities
Fuels, coolants, lubricants etc. .............................. 393
Card, KEYLESS-GO ..........................................................28
Cargo tie-down hooks ................................................... 200
Catalytic converter ........................................................ 220
Center console .................................................................. 24
Center console lighting ................................................. 185
Central locking switch .................................................... 50
Central locking system .................................................... 34
Automatic central locking .........................................52
Central locking switch ............................................... 50
Choosing global or selective mode .....................37, 43
Electronic main key .................................................... 29
408 Index
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car careIndex
Locking and unlocking ............................................ 36, 40
Low engine coolant level warning ..............................304
Lumbar support ............................................................... 74
MMaintenance ...................................................................209
Malfunction and indicator lamps
in the instrument cluster .........................................290
Malfunction and warning messages ...........................297
ACTIVE BODY CONTROL ......................................... 310
BATTERY/ALTERNATOR ..........................................299
BRAKE ASSIST ..........................................................300
BRAKE FLUID ............................................................ 301
BRAKE LINING WEAR ............................................. 301
COOLANT (coolant level) .........................................304
COOLANT (coolant temperature) ...........................305
CRUISE CONTROL ....................................................309
DISPLAY DEFECTIVE (engine control unit) .........298
DISPLAY DEFECTIVE (several systems) ...............298
DISTRONIC (DTR) ..................................................... 321
DOOR .......................................................................... 316
ELEC. STABIL. PROG. ...............................................303
ENGINE OIL LEVEL .......................................... 314, 318
ENTRANCE POSITION .............................................300HOOD .......................................................................... 317
KEY .............................................................................. 316
LIGHT SENSOR .................................................308, 320
LIGHTING SYSTEM .................................................. 306
PARKING BRAKE ..................................................... 302
SEAT BACKREST ....................................................... 315
SEAT BELT SYSTEM ................................................. 308
TELE AID .................................................................... 317
TELEPHONE - FUNCTION ....................................... 309
TIRE PRESSURE ........................................................ 312
TRUNK OPEN ........................................................... 302
WASHER FLUID ......................................................... 319
Malfunction/warning message memory .................... 136
Manual operation of sliding/pop-up roof .................. 369
Mechanical keys ............................................................... 47
Memory function ............................................................111
Mirror, exterior
Parking position ........................................................108
Mirror, exterior, adjusting ............................................107
Mirror, exteri or, p arki n g p o si tio n ,
front passenger side .................................................108
Mirror, exterior, rear view ............................................107
Mirror, inside, rear view ............................................... 106
Multicontour backrest ..................................................... 74
Multifunction display .................................................... 120
Audio systems ............................................................125
410 Index
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car careIndex
Express opening and closing .................................. 179
Opening and closing .................................................. 45
Synchronizing ........................................................... 180
Problems with your vehicle ........................................... 14
Product information .......................................................... 7
RRadio transmitters .........................................................208
Rain sensor
See intermittent wiping ........................................... 161
Rear passenger compartment
adjustable air outlets ................................................ 177
Rear view mirror
Inside, automatic antiglare ..................................... 106
Rear view mirrors .......................................................... 106
Exterior ....................................................................... 107
Interior ........................................................................ 106
Storing mirror positions .......................................... 106
Rear window defroster ...................................................176
Rear window sunshade ................................................. 186
Remote control ................................................................. 28
Battery replacement .................................................363
Removal and installation of
front seat head restraints .......................................... 71Replacement keys
Obtaining ...................................................................... 31
Replacing bulbs ............................................................. 354
Replacing wiper blades ................................................ 370
Reporting Safety Defects ................................................. 15
Reserve key ....................................................................... 30
Reserve warning lamp
Fuel reserve warning ............................................... 293
Residual engine heat utilization (REST) .................... 174
Roadside assistance ......................................................... 10
Roadside assistance call
See Tele Aid ............................................................... 210
Roof rack ......................................................................... 372
SSEAT BACKREST -
malfunction and warning messages ...................... 315
SEAT BELT SYSTEM -
malfunction and warning messages ..................... 308
Seat belts ........................................................................... 82
Fastening ......................................................................85
Operation ......................................................................86
Seat belt nonusage warning system .........................83
Unfastening .................................................................. 86