service MERCEDES-BENZ CLS COUPE 2012 Owners Manual

Disclaimer
Das folgen de PDF -Doku ment für die ses Fahrze ugmodell be zieht sich in allen
Sprachver sionen nur auf die Fahrz euge, d ie fü r den deutsche n Markt best immt
sind und die den deutschen Vorschriften entsprechen. Bitte wenden Sie sich an
Ihr en autorisierten Mer cedes-Benz Services tützpunkt, um ein gedruckt es Exem plar
für andere Fahrzeugmodelle und Fahrzeugmodelljahre zu erhalten.
Dieses PDF -Dokume nt stellt die aktuelle Version dar . Mögliche Abweic hungen zu
Ihrem konkreten Fahrzeug könnten nicht berücksichtigt sein, da Mercedes-Benz
seine Fahrzeuge st ändig dem neuest en Stand d er Technik anp asst, so wie
Änderungen in Form und Ausstattung vornimmt. Bitte beachten Sie daher, dass
dieses PDF-Dokument in keinem Fall das gedruckte Exemplar ersetzt, das mit
dem Fahrzeug ausgeliefert wurde.
Internal use only
Disclaimer
All language versions of the following PD\f document for this vehicle model
relate solel\b to vehicles intended for sale on the German market and which
correspond to German regulations.
Please contact \bour authorised Mercedes-Benz Service Centre to obtain
a printed version for other vehicle models and vehicle model \bears. This PD\f
document is the latest version. Possible variations to \bour vehicle ma\b not
be taken into account as Mercedes-Benz constantl\b updates their vehicles to
the state of the art and introduces changes in design and e\Dquipment. Please
therefore note that this PD\f document in no wa\b replaces the printed version
which was delivered with \bour vehicle.
Internal use only
Disclaimer
The following version of the Owner‘s Manual describes all models, series and
special equipment of your vehicle. Country-specific language variations are
possible. Please note that your vehicle might not be equipped with all the
described functions. This also affects safety-relevant systems and functions.
Please contact your authorised Mercedes-Benz dealership if you would like
to receive a printed Owner‘s Manual for other vehicle models and vehicle
model years.
The online Owner‘s Manual is the current and valid version. It is possible that
deviations affecting your specific vehicle could not be taken into account
as Mercedes-Benz constantly adapts its vehicles according to the latest
technology and makes changes to the form and the equipment.
Please also read the printed Owner‘s Manual, supplementary documents and
the digital Owner‘s Manual in the vehicle.
Copyright
All rights reserved. All texts, images and graphics are subject to copyright
and other laws for the protection of intellectual property. They may not be
copied or changed for any commercial use or for the purpose of being passed
on nor used on other webistes.

Welcome to the world of Mercedes-Benz
Before you first drive off, read this Owner's
Manual carefully and familiarise yourself with
yourv ehicle. For your own safety and alonger
vehicle life, follow the instructions and warn-
ing notices in this manual. Disregarding them
may lead to damage to the vehicle or personal
injury.
The equipment or model designation of your
vehicle may vary according to:
R model
R order
R country variant
R availability
The illustration sinthis manual show aleft-
hand-drive vehicle. On right-hand-drive vehi-
cles, the layout of componentsa nd controls
differs accordingly.
Mercedes-Benz is constantly updating its
vehicles to the state of the art.
Mercedes-Benz therefor ereserves the right
to introduce changes in the following areas:
R design
R equipment
R technical features
Therefore, descriptions may vary from those
of your own vehicle.
The following are integral componentsoft he
vehicle:
R Owner's Manual
R Service Booklet
R equipment-dependent supplements
Keep printed copies of the documents in the
vehicle at all times. If you sell the vehicle,
always pass the documents on to the new
owner.
i You can get to know the important fea-
tures of your vehicle in the interactive Own-
er's Manual on the Internet at:
http://www.mercedes-benz.de/
betriebsanleitung The technical documentation team at
Daimler AG wishes you safe and pleasant
motoring.
2185841181Z102 É2185841181Z1027ËÍ

1, 2,
3...
12 Vsocket
see Socket
4ETS
see ETS/4ETS (Electronic Trac-
tionS ystem)
4MATIC (permanent four-wheel
drive) .................................................. 184
4MATIC off-road system ...................184 A
ABS (Anti-lock Braking System) Display message ............................ 232
Function/notes ................................ 63
Important safety notes ....................63
Warning lamp ................................. 261
Activating/deactivating air-recir-
culation mode .................................... 131
Activating/deactivating cooling
with air dehumidification .................127
Active Blin dSpot Assist
Activating/deactivating (on-
board computer) ............................ 220
Display message ............................ 246
Function/notes ............................. 201
Active Driving Assistanc epackage .201
Active Lane Keepin gAssist
Activating/deactivating (on-
board computer) ............................ 220
Display message ............................ 246
Function/notes ............................. 204
Active light function .........................115
Active multicontour seat ..................100
Active Park Assist Display message ............................ 247
Active Parking Assist
Important safety notes ..................187
Active Service System
see ASSYST PLUS
ADAPTIVE BRAKE ................................. 68
Adaptive brake lamps .........................65
Adaptive Highbeam Assist Display message ............................ 240
Function/notes ............................. 116Adaptive Main-beam Assist
Switching on/off (on-board com-
puter) ............................................. 223
Additives (engine oil) ........................364
Airbags Front airba g(driver, front
passenger )....................................... 44
Important safety guidelines .............42
Kneeba g.......................................... .44
Pelvis airbag .................................... 45
Sidebag ............................................ 45
Triggering ......................................... 41
Windowba g...................................... 46
Air-conditionin gsystem
see Climate control
Airf ilter (white display message) ....243
AIRF LOW ........................................... 128
AIRMATIC Display message ............................ 243
Function/notes ............................. 181
Airp ressure
see Tyr epressure
Airv ents
Glove compartmen t....................... 137
Important safety notes ..................136
Rea r............................................... 137
Setting ........................................... 136
Setting the centre airv ents........... 137
Setting the sid eairvents ............... 137
Alarm system
see ATA (Anti-Theft Alarm system)
Ambient lighting
Setting the brightness (on-board
computer) ...................................... 223
Setting the colou r(on-board com-
puter) ............................................ .223
AMG RID ECONTROL sports sus-
pension ............................................... 183
Anti-glare film .................................... 293
Anti-loc kBraking System
se eA BS (Anti-lock Braking System)
Anti-Thef tAlarm system
se eA TA (Anti-Theft Alarm system)
Aquaplaning ....................................... 164
Ashtray ............................................... 282
Assistanc emenu (on-board com-
puter) ................................................. .218 4
Index

ASSYS
TPLUS
Displaying aservice message ........300
Hiding aservice message ..............300
Notes ............................................. 300
Resetting the service interva ldis-
pla y................................................ 300
Service message ............................ 300
Specia lservice requirements ......... 301
ATA (Anti-Theft Alarm system)
Activating/deactivating ...................71
Function .......................................... .71
Interior motion sensor .....................72
Switching off the alarm ....................71
Tow-awa yprotectio n........................ 71
ATTENTIO NASSIST
Activating/deactivating .................220
Display message ............................ 243
Function/notes ............................. 192
Authorised workshop
see Qualified specialist workshop
AUTO lights
Display message ............................ 239
see Lights
Automatic engine start (ECO start/
stop function) .................................... 146
Automatic engine switch-off (ECO
start/stop function) ..........................145
Automatic headlamp mode ..............111
Automatic transmission Accelerator pedal position .............151
Automatic drive program ...............152
Changing gea r............................... 151
DIRECT SELECT leve r..................... 149
Display message ............................ 254
Drive position (ECO start/stop
function) ........................................ 150
Drive program displa y.................... 149
Driving tips .................................... 151
Emergency running mode ..............156
Engaging drive position .................. 150
Engaging neutra l............................ 150
Engaging revers egear ................... 150
Engaging the par kposition ............ 149
Kickdow n....................................... 151
Manual drive program ....................154
Neutral (ECO start/stop function) .150
Overview ........................................ 148
Problem (fault) ............................... 156Progra
mselector button ................151
Pulling away ................................... 143
Selector leve r................................ 148
Shift range s................................... 153
Starting the engine ........................143
Steering wheel gearshift paddle s... 152
Transmission position displa y........ 149
Transmission position display
(DIREC TSELECT lever) ................... 149
Transmission positions ..................150
Automatic transmission emer-
gency runnin gmode ......................... 156
Auxiliary heating Activating/deactivating .................133
Activating/deactivating (on the
centre console ).............................. 133
Display message ............................ 255
Important safety notes ..................132
Problem (display message) ............136
Remote control .............................. 133
Setting ........................................... 225
Setting the departur etime ............ .135
Auxiliary ventilation
Activating/deactivating .................133
Activating/deactivating (on the
centre console ).............................. 133
Problem (display message) ............136
Remote control .............................. 133 B
Bag hook ............................................ 277
BAS (Brake Assist System) .................63
BAS PLU S(Brake Assist System
PLUS) .................................................... 64
Battery (key) Checking .......................................... 79
Important safety notes ....................79
Replacing ......................................... 79
Battery (vehicle)
Charging ........................................ 318
Display message ............................ 242
Important safety notes ..................316
Jump starting ................................. 319
Belt
see Seat belt
Belt force limiters (activation) ...........41 Index
5

Driver's door
see Door
Drive system
Active Blind Spot Assis t................. 201
Driving abroad
Service24h .................................... 301
Symmetrical dipped bea m............. 110
Driving on flooded roads ..................164
Driving safety system BAS PLUS (Brake Assist System
PLUS) .............................................. .64
Electroni cBrake-force Distribu-
tio n.................................................. 68
ESP ®
(Electroni cStability Pro-
gram) ............................................... 65
ETS/4ETS (Electroni cTraction
System) ........................................... 66
Important safety guidelines .............62
Driving safety systems
ABS (Anti-lock Braking System) .......63
ADAPTIVE BRAKE ............................. 68
Adaptive brake lamps ......................65
BAS (Brake Assist System) ..............63
Overview .......................................... 62
PRE-SAFE ®
Brake ............................ .68
Driving system
Active Lan eKeepin gAssist. ........... 204
Active Parking Assist .....................187
Driving systems
Active Driving Assistance pack-
age ................................................. 201
AIRMATIC ...................................... 181
AMG RIDE CONTROL sports sus-
pension .......................................... 183
ATTENTION ASSIST ........................192
Blind Spot Assist ............................ 197
Cruise control ................................ 165
Display message ............................ 243
Distronic Plu s................................ 170
HOLD function ............................... 179
Lane Keeping Assist ......................199
Lane package ................................ 197
Nigh tView Assist Plus ...................194
PARKTRONI C................................. 185
RAC ESTART (AMG vehicles) ..........180
Reversing camera ..........................190Speed Limi
tAssist ......................... 193
SPEEDTRONIC ............................... 168
Driving tips
AMG cerami cbrakes ..................... 163
Aquaplaning ................................... 164
Automatic transmission .................151
Brakes ........................................... 162
Downhill gradient ........................... 162
Driving abroad ............................... 110
Driving in winter ............................ .164
Driving on flooded road s................ 164
Driving on wet road s...................... 164
General .......................................... 161
Icy road surfaces ........................... 165
Limited braking efficiency on sal-
ted road s....................................... 163
New brake pads/linings ................163
Running-in tips ............................... 140
Snow chains .................................. 331
Symmetrical dipped bea m............. 110
Wet road surface ........................... 163
DVD audio
Operating (on-board computer) .....216
DVD video
Operating (on-board computer) .....216 E
EASY-ENTRY feature Activating/deactivating .................226
Function/notes ............................. 104
EASY-EXIT feature
Crash-responsive ........................... 104
Function/notes ............................. 104
Switching on/off ........................... 226
EASY-PACKc onvenience box ...........277
EBD (electronic brake force distri-
bution) Display message ............................ 234
Function/notes ................................ 68
ECOd isplay
Function/notes ............................. 161
On-board computer .......................213
ECOs tart/stop function
Deactivating/activating .................145
General information .......................144
Electrical fuses
see Fuses Index
9

L
Lamps see Warning and indicator lamps
Lane detection (automatic)
see Lan eKeeping Assist
Lane Keeping Assist
Activating/deactivating .................220
Display message ............................ 246
Function/informatio n.................... 199
Lane package ..................................... 197
Lap time (RACETIMER) ......................228
Lashing eyelets ................................. 276
Lighting see Lights
Lights
Activating/deactivating the Intel-
ligent Ligh tSystem ........................ 222
Activating/deactivating the inte-
rior lighting delayed switch-off .......224
Active light function .......................115
Automatic headlamp mode ............111
Cornering light function .................115
Dipped-bea mheadlamps ............... 111
Driving abroad ............................... 110
Foglamps (extende drange )........... 116
Hazard warning lamps ...................114
Headlamp flasher ........................... 114
Ligh tswitc h................................... 110
Main-beam headlamps ................... 113
Motorway mode ............................. 115
Parking lamps ................................ 113
Rea rfoglamp ................................. 112
Setting brightness for display/
switches (on-board computer) .......222
Setting the ambient lighting
brightness (on-board computer) ....223
Setting the ambient lighting col-
our (on-board computer) ................ 223
Side lamps ..................................... 112
Switching Adaptive Highbeam
Assist on/off ................................. 223
Switching the daytime driving
lights on/off (on-board computer) .222
Switching the exterio rlighting
delayed switch-off on/off (on-
board computer )............................ 223Switching the surround lighting
on/off (on-board computer)
..........223
Turn signals ................................... 113
see Changing bulbs
see Interior lighting
Light sensor (display message) .......239
LIMi ndicator lamp
Cruise control ................................ 165
DISTRONI CPLUS ........................... 172
Variabl eSPEEDTRONIC .................168
Limiting the speed
see SPEEDTRONIC
Loading guidelines ............................272
Locking see Centra llocking
Locking (doors)
Automatic ........................................ 84
Emergency locking ........................... 84
From insid e(central locking but-
ton) .................................................. 83
Locking centrally
see Centra llocking
Locking verification signal (on-
board computer) ............................... 225
Lumbar support Adjusting ....................................... 101
Adjusting the 4-way lumba rsup-
por t................................................ 101
Luxu ry head restraint .........................99 M
M+S tyres ........................................... 330
Main-beam headlamps Display message ............................ 238
Switching Adaptive Highbeam
Assist on/off ................................. 117
Switching on/off ........................... 113
Massag efunction (PULSE) ...............101
Matt finish (cleaning instructions) ..303
Memory card (audio) .........................216
Memory function ............................... 107
Mercedes-Benz Service Centre see Qualified specialist workshop
Message memory (on-board com-
puter) ................................................. .231
Messages see Display messages Index
13

Mirror
see Vanity mirror (in sun visor)
Mirrors
see Exterior mirrors
see Rear-view mirror
Mobile phone
Frequencies ................................... 357
Installatio n..................................... 357
Menu (on-board computer) ............217
Notes/placing in the bracket ......... 284
Sliding adapter ............................... 286
Transmission output (maximum ).... 357
Modifying the programming (key) .....78
MOExtende dtyres ............................ .313
Motorway mode ................................ 115
MP3 Operating ...................................... .216
see Separate operating instructions
Multifunctio ndisplay
Function/notes ............................. 211
Permanent displa y......................... 221
Multifunctio nsteering wheel
Operating the on-board computer .210
Overview .......................................... 33N
Navigation Menu (on-board computer) ............214
NECK-PRO head restraints
Operation ........................................ .46
Resettin gafter bein gtriggered ........47
NECK-PRO luxury head restraints
Operation ........................................ .46
Resettin gafter bein gtriggered ........47
Night View Assist Plus
Activating/deactivating .................195
Cleaning ......................................... 305
Function/notes ............................. 194
Problem (fault) ............................... 197
Notes on runnin ginanew vehicle ..140 O
Occupant safety Childre ninthe vehicle ..................... 52
Important safety notes ....................40
Odometer
see Total distance recorder
see Trip meter
Oil
see Engine oil
On-board computer
AMG menu ..................................... 228
Assistance menu ........................... 218
Audi omenu ................................... 215
Convenience submenu ..................226
Displaying aservice message ........300
Display messages ..........................231
DISTRONI CPLUS ........................... 176
Factory setting submenu ...............227
Heating submenu ........................... 225
Important safety notes ..................208
Instrument cluster submenu ..........221
Ligh tsubmenu ............................... 222
Menu overview .............................. 212
Message memory .......................... 231
Navigation menu ............................ 214
Operating the TV ............................ 216
Operating vide oDVD ..................... 216
Operation ....................................... 210
RACETIMER ................................... 228
Service menu ................................. 220
Settings menu ............................... 221
Standard displa y............................ 212
Telephone menu ............................ 217
Trip menu ...................................... 212
Vehicle submenu ........................... 224
Operatin gsystem
see On-board computer
Outside temperature display ...........210
Overhead control panel ......................37
Override feature Rea rside windows ........................... 62 P
Pain tcode .......................................... 359
Paintwork (cleaning instructions) ...303
Pani calarm .......................................... 4014
Index

Remote control
Auxiliary heating/ventilation .......... 133
Changing the batterie s(au xiliary
heating) ......................................... 135
Garage door opene r....................... 287
Programming (garage door
opener) .......................................... 287
Replacing the battery (auxiliary
heatin gremote control) .................... 135
Reserve (fue ltank)
see Fuel
Reserve fuel
Display message ............................ 242
Warning lamp ................................. 267
Residual heat (climate control) ........132
Restrain tsystem
see SRS (Supplemental Restraint
System)
Rev counter ........................................ 210
Reverse gear (selector lever) ...........148
Reversing camera Cleaning instructions .....................305
Function/notes ............................. 190
Switching on/off ........................... 191
Reversing lamp
Changing bulbs .............................. 120
Reversing lamp (display message) ..239
Roller sunblind Rea rwindow .................................. 282
Roof carrier ........................................ 278
Roof lining and carpets (cleaning
instructions) ...................................... 307
Roof load (maximum) ........................366 S
Safety Childre ninthe vehicle ..................... 52
Child restraint systems ....................52
Safety system
see Driving safety system
Seat
Seat backres tdisplay message .....255
Seat belt
Adjusting the driver's and front-
passenger sea tbelt ......................... 50
Adjusting the height ......................... 50
Belt force limiter .............................. 51Belt tensioner
.................................. 51
Cleaning ......................................... 307
Display message ............................ 235
Fastening ......................................... 49
Important safety guidelines .............48
Rea rseat belt status indicator .........51
Releasing ......................................... 50
Switching bel tadjustment on/off
(on-board computer) ......................227
Warning lamp ................................. 259
Warning lamp (function) ................... 51
Seats
Adjusting (electrically). ....................98
Adjusting lumba rsuppor t.............. 101
Adjusting the 4-way lumba rsup-
por t................................................ 101
Adjusting the head restraint ............98
Cleaning the cover .........................306
Correct driver's sea tposition ........... 96
Important safety notes ....................97
Seat heating problem ....................102
Seat ventilation problem ................102
Storing settings (memory func-
tion) ............................................... 107
Switching sea theating on/off .......101
Switching the sea tventilation on/
off .................................................. 102
Selector lever
Cleaning ......................................... 306
Sensors (cleaning instructions) .......304
Service see ASSYST PLUS
Service Centre
see Qualified specialist workshop
Service menu (on-board computer) .220
Service products Brake fluid ..................................... 365
Coolant (engine) ............................ 365
Engine oil ....................................... 363
Fuel ................................................ 360
Important safety notes ..................359
Washer fluid .................................. .366
Settings
Factory (on-board computer) .........227
On-board computer .......................221
Settin gthe air distribution ...............129
Settin gthe airflow ............................ 129
SETUP (on-board computer) .............228 16
Index

Type identificatio
nplate
see Vehicl eide ntificatio nplate
Tyr epressure
Calling up (on-board computer )..... 334
Display message ............................ 250
Not reached (TIREFIT) ....................315
Reached (TIREFIT) ..........................315
Recommended ............................... 331
Tyre pressure los swarning
Important safety notes ..................332
Restarting ...................................... 333
Tyre pressure monitor
Checking the tyre pressure elec-
tronically ........................................ 334
Function/notes ............................. 334
Restarting ...................................... 335
Warning lamp ................................. 270
Warning message .......................... 335
Tyres
Changing awheel .......................... 336
Checking ........................................ 329
Directio nofrotation ...................... 336
Display message ............................ 250
Important safety notes ..................328
MOExtended tyres .........................330
Replacing ....................................... 336
Service life ..................................... 329
Storing ........................................... 337
Tyr esize (data) .............................. 341
Tyr etread ...................................... 329
see Flat tyre U
Unladen weight ................................. 366
Unlocking Emergency unlocking .......................84
From insid ethe vehicle (central
unlocking button) ............................. 83 V
Vanity mirror (in sun visor) ..............281
Variable SPEEDTRONIC see SPEEDTRONIC
Vehicle
Correct use ...................................... 24
Data acquisition ............................... 24Display message
............................ 254
Electronics ..................................... 357
Equipment ....................................... 22
Implied warranty .............................. 24
Individua lsettings .......................... 221
Leaving parked up .........................161
Locking (in an emergency) ...............84
Locking (key )................................... 77
Lowering ........................................ 340
Pulling away ................................... 143
Raising ........................................... 338
Registration ..................................... 24
Securing from rolling away ............337
Towing away .................................. 320
Transporting .................................. 323
Unlocking (in an emergency) ...........84
Unlocking (key )................................ 77
Vehicle data ................................... 366
Vehicle data ....................................... 366
Vehicle dimensions ...........................366
Vehicle emergency locking ................84
Vehicle identification number see VIN
Vehicle identification plate ..............359
Vehicle level AIRMATIC ...................................... 181
AMG RIDE CONTROL sports sus-
pension .......................................... 183
Vehicle level (display message) .......243
Vehicle tool kit .................................. 311
Vehicle weights ................................. 366
Video Operating the DVD ......................... 216
VIN ...................................................... 359 W
Warning and indicator lamps ABS ................................................ 261
Brakes ........................................... 260
Distance warning signa l................. 269
ESP ®
.............................................. 263
ESP ®
OFF ....................................... 264
LIM (cruise control) ........................ 165
LIM (DISTRONIC PLUS) ..................172
LIM (variable SPEEDTRONIC )......... 168
Overview .................................. 32, 258
PASSENGER AIRBAG OFF ................54 Index
19

Protection of the environment
General notes
H
Environmental note
Daimler's declared policy is one of compre-
hensive environmental protection.
The objectives are for the natural resources
which form the basis of our existence on this
planet to be used sparingly and in amanner
which takes the requirements of both nature
and humanity into account.
You too can help to protect the environment
by operating your vehicle in an environmen-
tally-responsible manner.
Fuel consumption and the rate of engine,
transmission, brake and tyre wear depend on
the following factors:
R operating condition sofyour vehicle
R your personal driving style
You can influence both factors. You should
bear the following in mind:
Operating conditions:
R avoid short trips as these increase fuel con-
sumption.
R make sure that the tyre pressures are
always correct.
R do not carry any unnecessary weight.
R keep an eye on the vehicle's fuel consump-
tion.
R remove roof racks once you no longer need
them.
R ar egularly serviced vehicle will contribute
to environmental protection. You should
therefore adhere to the service intervals.
R always have service work carried out at a
qualified specialist workshop.
Personal driving style:
R do not depress the accelerator pedal when
startingt he engine.
R do not warm up the engine with the vehicle
stationary.
R drive carefully and maintain asafe distance
from the vehicle in front. R
avoid frequent, sudden acceleration.
R change gear in good time and use each gear
only up to Ôof its maximum engine speed.
R switch off the engine in stationary traffic. Returning an end-of-life vehicle
Mercedes-Benz will take back your
Mercedes-Benz to dispose of it in an environ-
mentally responsible manner, in accordance
the European Union (EU) End of Life Vehicles
Directive.
The End of Life Vehicles Directive applies to
vehicles with agross vehicle weight of up to
3.5 t, in accordance with national regulations.
For several years, Mercedes-Benz has been
meeting all the legal requirements for a
design which allowsf or recycling and re-use.
There is anetwork of return points and dis-
assembly plants which can recycle your vehi-
cle in an environmentally-responsible man-
ner. The methods employed in vehicle and
parts recycling are constantly being devel-
oped and improved. This means that your
Mercedes-Benz will also continue to meet
even the increased recycling quotas in the
future in good time. You can obtain further
information from your national Mercedes-
Benz homepage or your national hotline num-
ber. Product information
Mercedes-Benz recommends that you use
genuine Mercedes-Benz parts, conversion
parts and accessories that have been
approved for the type of vehicle.
Mercedes-Benz tests genuine parts and con-
version parts and accessories that have been
specifically approved for your vehicle for their
reliability, safety and suitability. Despite
ongoing market research, Mercedes-Benz is
unable to assess other parts. Therefore,
Mercedes-Benz accepts no responsibility for
the use of such parts in Mercedes-Benz vehi- Introduction
21 Z