Electrical system

Chapter overview

• Technical data
  1
• 1 Safety information
  1
• 1.1 Safety precautions when working on vehicles with a start/stop system
  1
• 2 Repair instructions
  2
• 2.1 Contact corrosion
  2
• 2.2 Routing and attachment of lines
  2
• 3 Battery
  3
• 3.1 Battery - general notes
  3
• 3.2 Types of battery
  3
• Starter, current supply, CCS
  4
• 1 Battery
  4
• 1.1 Assembly overview - battery
  4
• 1.2 Removing and installing battery
  7
• 1.3 Disconnecting and connecting battery
  14
• 1.4 Removing and installing battery tray
  17
• 1.5 Checking battery
  18
• 1.6 Charging battery
  19
• 1.7 Removing and installing earth wire with battery monitor control unit J367
  19
• 1.8 Adapting battery monitor control unit J367
  21
• 2 Alternator
  22
• 2.1 Assembly overview - alternator
  22
• 2.2 Removing and installing alternator
  23
• 2.3 Checking alternator
  29
• 2.4 Removing and installing poly V-belt pulley
  30
• 2.5 Removing and installing voltage regulator
  37
• 3 Starter motor
  40
• 3.1 Assembly overview – starter
  40
• 3.2 Removing and installing starter
  41
• 4 Cruise control system (CCS)
  46
• 5 Start/stop system
  47
• 5.1 General description - start/stop system
  47
• 5.2 Overview of fitting locations - start/stop system
  47
• 6 Adaptive cruise control
  48
• 6.1 Overview of fitting locations - adaptive cruise control
  48
• 6.2 Removing and installing automatic distance control unit
  48
• 6.3 Calibrating adaptive cruise control
  49
• Gauges, instruments
  50
• 1 Dash panel insert
  50
• 1.1 Assembly overview - dash panel insert
  50
• 1.2 Assembly overview - head-up display
  51
• 1.3 Removing and installing dash panel insert KX2
  52
• 1.4 Removing and installing control unit for head-up display
  55
• 2 Horn
  57
• 2.1 Assembly overview - horn
  57
• 2.2 Removing and installing treble horn H2 and bass horn H7
  57
• 2.3 Removing and installing bracket for horn H2 / H7
  58
• Windscreen wash/wipe system
  60
• 1 Windscreen wiper system
  60
• 1.1 Assembly overview - windscreen wiper system
  60
• 1.2 Moving wipers to service position
  63
• 1.3 Removing and installing wiper blade
  63
• 1.4 Removing and installing wiper arms
  64
• 1.5 Adjusting wiper arms
  66
• 1.6 Removing and installing wiper motor V
  67
• 1.7 Renewing wiper motor
  68
• 1.8 Deactivating APP function of wiper motor
  70
• 1.9 Removing and installing rain and light sensor
  71
• 2 Windscreen washer system
  74
• 2.1 Assembly overview - windscreen washer system
  74
• 2.2 Removing and installing washer fluid reservoir
  78
• 2.3 Removing and installing windscreen washer fluid level sender
  82
• 2.4 Removing and installing windscreen washer pump
  84
• 2.5 Removing and installing washer jets
  85
• 2.6 Adjusting spray jets
  86
• 3 Rear window wiper system
  87
• 3.1 Assembly overview - rear window wiper system
  87
• 3.2 Removing and installing wiper blade
  88
• 3.3 Removing and installing wiper arm
  88
• 3.4 Adjusting wiper arm
  89
• 3.5 Removing and installing rear window wiper motor V12
  90
• 4 Rear window washer system
  92
• 4.1 Assembly overview - rear window washer system
  92
• 4.2 Removing and installing washer fluid reservoir
  95
• 4.3 Removing and installing rear window washer pump
  95
• 4.4 Removing and installing spray jet
  95
• 4.5 Adjusting spray jet
  96
• 5 Headlight washer system
  97
• 5.1 Assembly overview - headlight washer system
  97
• 5.2 Removing and installing washer fluid reservoir
  99
• 5.3 Removing and installing headlight washer system pump V11
  99
• 5.4 Removing and installing pop-up cylinder
  100
• 5.5 Adjusting spray jets
  101
• 6 Washer fluid lines
  103
• 6.1 Repairing washer fluid lines
  103
• Lights, bulbs, switches - exterior
  104
• 1 Headlights
  104
• 1.1 Assembly overview - headlight
  104
• 1.2 Removing and installing headlight
  112
• 1.3 Adjusting headlights
  113
• 1.4 Adjusting headlight installation position
  113
• 1.5 Removing and installing front turn signal bulb M5 / M7
  114
• 1.6 Installing repair kit for headlight housing
  115
• 1.7 Converting headlights from driving on right to driving on left
  117
• 1.8 Converting headlights from driving on left to driving on right
  117
• 1.9 Removing and installing headlight range control motor V48 / V49
  118
• 1.10 Removing and installing dipped beam bulb
  124
• 1.11 Removing and installing headlight main beam bulb M30 / M32
  129
• 1.12 Removing and installing side light bulb M1 / M3
  134
• 1.13 Removing and installing daytime running light bulb L174 / L175
  134
• 1.14 Removing and installing LED modules for daytime running light and side light L176 / L177
  135
• 1.15 Removing and installing bulbs for cornering light L148 / L149
  137
• 1.16 Removing and installing output module for headlight J667 / J668
  137
• 1.17 Removing and installing output module 1 for LED headlight A27 / A31
  140
• 1.18 Removing and installing swivel module position sensor G474 / G475
  142
• 1.19 Removing and installing dynamic cornering light control motor V318 / V319
  142
• 2 Fog lights
  143
• 2.1 Assembly overview - fog lights
  143
• 2.2 Removing and installing fog light
  143
• 2.3 Removing and installing fog light bulb L22 / L23
  145
• 3 Lights in exterior mirror
  147
• 3.1 Assembly overview - lights in exterior mirror
  147
• 3.2 Removing and installing turn signal
  148
• 3.3 Removing and installing entry light in exterior mirror
  150
• 4 Tail lights
  151
• 4.1 Assembly overview - tail lights in body
  151
• 4.2 Assembly overview - tail lights in rear lid
  152
• 4.3 Removing and installing tail light in rear lid
  152
• 4.4 Adjusting installation position of tail light
  153
• 4.5 Removing and installing tail light cluster
  154
• 4.6 Removing and installing tail light bulb M2 / M4
  155
• 4.7 Removing and installing rear fog light bulb L46 / L47
  155
• 4.8 Removing and installing brake and tail light bulb M21 / M22
  155
• 4.9 Removing and installing reversing light bulb
  155
• 4.10 Removing and installing turn signal bulb
  156
• 5 High-level brake light
  157
• 5.1 Assembly overview - high-level brake light
  157
• 5.2 Removing and installing high-level brake light
  157
• 6 Number plate light
  160
• 6.1 Assembly overview – number plate lights
  160
• 6.2 Removing and installing number plate light X4 / X5
  161
• 6.3 Removing and installing bulb for number plate light X4 / X5
  161
• 7 Entry and start authorisation system
  162
• 7.1 Overview of fitting locations - entry and start authorisation system
  162
• 7.2 Overview of fitting locations - keyless entry system
  165
• 7.3 Removing and installing interface for entry and start system J965
  167
• 7.4 Removing and installing door exterior handle contact sensor G415 / G416
  168
• 7.5 Removing and installing interior aerial 1 for entry and start system R138
  168
• 7.6 Removing and installing interior aerial 2 for entry and start system R139
  169
• 7.7 Removing and installing driver side aerial for entry and start system R134
  170
• 7.9 Removing and installing rear bumper aerial for entry and start system R136
  170
• 7.11 Removing and installing rear lid power opening control unit J938
  172
• 7.12 Removing and installing rear lid power opening sender G750 / G760
  172
• 8 Steering column switch module
  173
• 8.1 Assembly overview - steering column switch module
  173
• 8.2 Removing and installing lock cylinder
  175
• 8.3 Removing and installing ignition key withdrawal lock solenoid N376
  177
• 8.4 Removing and installing ignition/starter switch
  178
• 8.5 Removing and installing steering column switch module
  179
• 8.6 Removing and installing steering column electronics control unit J527
  184
• 8.7 Removing and installing turn signal switch E2
  190
• 8.8 Removing and installing intermittent wiper switch E22
  192
• 8.9 Removing and installing immobiliser reader coil D2
  192
• 8.10 Removing and installing base for steering column combination switch
  193
• 8.11 Removing and installing steering lock housing
  194
• 9 Parking aid
  195
• 9.1 Assembly overview – parking aid
  195
• 9.2 Removing and installing parking aid control unit J446
  198
• 9.3 Removing and installing front parking aid warning buzzer H22
  200
• 9.4 Removing and installing rear parking aid warning buzzer H15
  201
• 9.5 Removing and installing front parking aid senders
  201
• 9.6 Removing and installing rear parking aid senders
  202
• 10 Park assist steering
  203
• 10.1 Assembly overview - park assist steering
  203
• 10.2 Removing and installing park assist steering control unit J791
  204
• 10.3 Removing and installing front senders
  204
• 10.4 Removing and installing rear senders
  205
• 11 Automatic headlight range control
  206
• 11.1 Assembly overview - automatic headlight range control
  206
• 12 Towing bracket
  213
• 12.1 Assembly overview - towing bracket socket
  213
• 12.2 Trailer socket U10
  213
• 12.3 Removing and installing trailer detector control unit J345
  214
• Lights, bulbs, switches - interior
  215
• 1 Lights
  216
• 1.1 Overview of fitting locations - lights in dash panel
  217
• 1.2 Overview of fitting locations - lights in front doors
  218
• 1.3 Overview of fitting locations - lights in rear doors
  219
• 1.4 Overview of fitting locations - lights in centre console
  220
• 1.5 Overview of fitting locations - lights in luggage compartment
  221
• 1.6 Overview of fitting locations - lights in roof trim
  222
• 1.7 Removing and installing glove compartment light W6
  223
• 1.8 Replacing bulb for glove compartment light W6
  224
• 1.9 Removing and installing front footwell light K268 / K269
  225
• 1.10 Removing and installing front footwell illumination bulb L151 / L152
  225
• 1.11 Removing and installing Central locking SAFELOCK function warning lamp K133
  226
• 1.12 Removing and installing reflectors in door
  226
• 1.13 Removing and installing entry light W92 / W93
  227
• 1.14 Removing and installing interior door handle illumination bulb L146 / L147
  227
• 1.15 Removing and installing rear interior door handle illumination bulb L133 / L134
  228
• 1.17 Removing and installing light 1 for rear door background lighting L201 / L202
  228
• 1.18 Removing and installing roof ambient lighting bulb W76 / W77
  229
• 1.19 Removing and installing selector lever position display Y26
  230
• 1.20 Removing and installing luggage compartment light W3
  230
• 1.21 Removing and installing electric torch R280
  231
• 1.22 Removing and installing surround lighting 1 in rear lid W61
  231
• 1.23 Removing and installing illuminated vanity mirror W20 / W14
  232
• 1.24 Removing and installing bulb for front interior light W1
  233
• 1.25 Removing and installing bulb for rear interior light W43
  235
• 1.26 Removing and installing bulb for front reading light W13 / W19
  236
• 1.27 Removing and installing bulb for rear reading light W11 / W12
  236
• 1.28 Renewing bulb of rear interior light W47 / W48
  237
• 2 Controls
  239
• 2.1 Overview of fitting locations - controls in dash panel
  240
• 2.2 Overview of fitting locations - controls in front doors
  242
• 2.3 Overview of fitting locations - controls in rear doors
  243
• 2.4 Overview of fitting locations - controls in centre console
  244
• 2.5 Overview of fitting locations - controls in luggage compartment
  245
• 2.6 Overview of fitting locations - controls in roof trim
  246
• 2.7 Removing and installing rotary light switch EX1
  248
• 2.8 Removing and installing headlight range control regulator E102
  248
• 2.9 Removing and installing switch for Head-up Display E736
  249
• 2.10 Removing and installing TCS and ESP button E256
  250
• 2.11 Removing and installing parking aid button E266
  250
• 2.12 Removing and installing park assist steering button E581
  250
• 2.13 Removing and installing Start/Stop operation button E693
  250
• 2.14 Removing and installing driving mode selection button E735
  251
• 2.15 Removing and installing switch module in centre console EX23 / EX30
  251
• 2.16 Removing and installing operating unit for driving mode selection E881
  252
• 2.17 Removing and installing hazard warning light switch EX3
  254
• 2.18 Removing and installing buttons for seat heating E653 / E654
  254
• 2.19 Removing and installing glove compartment light switch E26
  254
• 2.20 Removing and installing exterior mirror adjuster EX11
  255
• 2.21 Removing and installing operating unit for window regulator in driver door E512
  256
• 2.22 Removing and installing front passenger side window regulator button E716
  256
• 2.23 Removing and installing driver side interior locking button for central locking system E308
  257
• 2.24 Removing and installing rear lid remote release button E233
  257
• 2.26 Removing and installing door contact switch F2 / F3
  259
• 2.27 Removing and installing rear window regulator button E711 / E713
  259
• 2.28 Removing and installing rear door contact switches F10 / F11
  260
• 2.30 Removing and installing the starter button E378
  261
• 2.31 Removing and installing rear lid warning buzzer H32
  261
• 2.32 Removing and installing rear lid contact switch
  262
• 2.33 Removing and installing rear lid closure button E574
  262
• 2.35 Removing and installing vanity mirror contact switch F147 / F148
  263
• 2.36 Removing and installing sunroof button E325
  264
• 2.37 Removing and installing front interior light/reading light
  264
• 2.38 Removing and installing rear interior light/reading light
  265
• 2.39 Removing and installing front reading light button E633 / E634
  268
• 3 Anti-theft alarm
  269
• 3.1 Assembly overview - interior monitor
  269
• 3.2 Removing and installing alarm horn H12
  270
• 3.3 Removing and installing anti-theft alarm sensor G578
  271
• 4 Lane change assist
  274
• 4.1 Assembly overview - lane change assist
  274
• 4.2 Removing and installing lane change assist warning lamp in exterior mirror K311 / K312
  275
• 4.3 Removing and installing lane change assist control unit J769 / J770
  275
• 4.4 Calibrating lane change assist
  276
• 5 Front camera for assist systems
  283
• 5.1 Removing and installing front camera for driver assist systems
  283
• 6 Cigarette lighter, socket
  284
• 6.1 Assembly overview - DC/AC converter with socket, 12 V-230 V
  284
• 6.2 Removing and installing cigarette lighter U1
  285
• 6.3 Removing and installing socket illumination bulb L42
  285
• 6.4 Removing and installing rear cigarette lighter illumination bulb L32
  285
• 6.5 Removing and installing electric socket U
  285
• 6.6 Removing and installing DC/AC converter with socket, 12 V-230 V U13
  285
• Wiring
  287
• 1 Relay carriers, fuse holders, electronics boxes
  287
• 1.1 Overview of fitting locations - relay carriers, fuse holders, E-boxes
  287
• 1.2 Removing and installing electronics box (E-box)
  291
• 1.3 Removing and installing relay and fuse holder in electronics box
  293
• 1.4 Removing and installing relay and fuse carrier behind dash panel
  295
• 1.5 Removing and installing main fuse carrier
  297
• 2 Control units
  299
• 2.1 Overview of fitting locations - control units
  299
• 2.2 Assembly overview - onboard supply control unit
  302
• 2.3 Assembly overview - data bus diagnostic interface
  304
• 2.4 Removing and installing onboard supply control unit J519
  305
• 2.5 Removing and installing data bus diagnostic interface J533
  309
• 2.6 Removing and installing bracket for onboard supply control unit J519
  311
• 2.7 Renewing bracket for onboard supply control unit J519
  313
• 2.8 Removing and installing parking aid control unit J446 / park assist steering control unit J791
  313
• 2.9 Removing and installing rear lid control unit J605
  314
• 3 Connectors
  315
• 3.1 Repairing electrical wiring harnesses and plug-in connections
  315
• 4 Releasing and dismantling connector housings
  316
• 5 Repairing aerial wires
  317
• 6 Fibre optic cables
  318
• 7 Vehicle diagnosis, testing and information systems
  319