Electrical system

Chapter overview

• Technical data
  1
• 1 Safety information
  1
• 1.1 Safety measures when working on vehicles with 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
  18
• 1.5 Checking battery
  20
• 1.6 Charging battery
  20
• 1.7 Removing and installing earth wire with battery monitor control unit J367
  20
• 1.8 Adapting battery monitor control unit J367
  23
• 2 Alternator
  24
• 2.1 Assembly overview - alternator
  24
• 2.2 Removing and installing alternator
  26
• 2.3 Checking alternator
  33
• 2.4 Removing and installing poly V-belt pulley
  34
• 2.5 Removing and installing voltage regulator
  43
• 3 Starter motor
  47
• 3.1 Assembly overview – starter
  47
• 3.2 Removing and installing starter
  49
• 4 Cruise control system (CCS)
  57
• 5 Start/stop system
  58
• 5.1 General description - start/stop system
  58
• 5.2 Overview of fitting locations - start/stop system
  58
• 5.3 Removing and installing voltage stabiliser
  59
• 6 Adaptive cruise control
  61
• 6.1 Overview of fitting locations - adaptive cruise control
  61
• 6.2 Removing and installing automatic distance control unit
  62
• 6.3 Calibrating adaptive cruise control
  63
• Gauges, instruments
  65
• 1 Dash panel insert
  65
• 1.1 Assembly overview - dash panel insert
  65
• 1.2 Assembly overview - head-up display
  67
• 1.3 Removing and installing dash panel insert KX2
  69
• 1.4 Removing and installing control unit for head-up display
  74
• 2 Clock
  76
• 2.1 Removing and installing clock
  76
• 3 Horn
  77
• 3.1 Assembly overview - horn
  77
• 3.2 Removing and installing treble horn H2 and bass horn H7
  77
• Windscreen wash/wipe system
  80
• 1 Windscreen wiper system
  80
• 1.1 Assembly overview - windscreen wiper system
  80
• 1.2 Moving wipers to service position
  83
• 1.3 Removing and installing wiper blade
  84
• 1.4 Removing and installing wiper arms
  85
• 1.5 Adjusting wiper arms
  87
• 1.6 Removing and installing wiper motor V
  88
• 1.7 Renewing wiper motor
  90
• 1.8 Deactivating APP function of wiper motor
  92
• 1.9 Removing and installing rain and light sensor
  93
• 2 Windscreen washer system
  97
• 2.1 Assembly overview - windscreen washer system
  97
• 2.2 Removing and installing washer fluid reservoir
  103
• 2.3 Removing and installing windscreen washer fluid level sender
  107
• 2.4 Removing and installing windscreen washer pump
  109
• 2.5 Removing and installing spray jets
  111
• 2.6 Adjusting spray jets
  112
• 3 Rear window wiper system
  114
• 3.1 Assembly overview - rear window wiper system
  114
• 3.2 Removing and installing wiper blade
  114
• 3.3 Removing and installing wiper arm
  115
• 3.4 Adjusting wiper arm
  116
• 3.5 Removing and installing rear window wiper motor V12
  117
• 4 Rear window washer system
  120
• 4.1 Assembly overview - rear window washer system
  120
• 4.2 Removing and installing washer fluid reservoir
  121
• 4.3 Removing and installing rear window washer pump
  122
• 4.4 Removing and installing spray jet
  122
• 4.5 Adjusting spray jet
  122
• 5 Headlight washer system
  123
• 5.1 Assembly overview - headlight washer system
  123
• 5.2 Removing and installing washer fluid reservoir
  124
• 5.3 Removing and installing headlight washer system pump V11
  125
• 5.4 Removing and installing pop-up cylinder
  126
• 5.5 Removing and installing spray jets
  129
• 5.6 Adjusting spray jets
  130
• 6 Washer fluid lines
  131
• 6.1 Repairing washer fluid lines
  131
• Lights, bulbs, switches - exterior
  132
• 1 Headlights
  133
• 1.1 Assembly overview – headlight
  133
• 1.2 Removing and installing headlight
  142
• 1.3 Adjusting headlights
  146
• 1.4 Adjusting headlight installation position
  146
• 1.5 Removing and installing front turn signal bulb M5/M7
  148
• 1.6 Installing repair kit for headlight housing
  149
• 1.7 Converting headlights from driving on right to driving on left
  152
• 1.8 Converting headlights from driving on left to driving on right
  152
• 1.9 Removing and installing headlight range control motor V48/V49
  153
• 1.10 Removing and installing dipped-beam headlight bulb
  160
• 1.11 Removing and installing headlight main beam bulb M30/M32
  165
• 1.12 Removing and installing side light bulb M1/M3
  172
• 1.13 Removing and installing daytime running light bulb L174/L175
  174
• 1.15 Removing and installing bulbs for cornering light L148/L149
  178
• 1.16 Removing and installing headlight fan V407/V408
  180
• 1.17 Removing and installing output module for headlight J667/J668
  182
• 1.19 Removing and installing output module 1 for LED headlights A27/A31
  186
• 1.20 Removing and installing control motor sender for VARILIS headlight G695/G696
  189
• 1.21 Removing and installing control motor for VARILIS headlight V446/V447
  189
• 1.22 Removing and installing swivel module position sensor G474/G475
  190
• 1.23 Removing and installing dynamic cornering light control motor V318/V319
  190
• 2 Fog lights
  191
• 2.1 Assembly overview - fog lights
  191
• 2.2 Removing and installing fog light
  191
• 2.3 Removing and installing fog light bulb L22/L23
  193
• 3 Lights in exterior mirror
  195
• 3.1 Assembly overview - lights in exterior mirror
  195
• 3.2 Removing and installing turn signal
  197
• 3.3 Removing and installing entry light in exterior mirror
  199
• 4 Tail light clusters
  200
• 4.1 Assembly overview - tail light cluster in body
  200
• 4.2 Assembly overview - tail lights in rear lid
  201
• 4.3 Removing and installing tail light in rear lid
  202
• 4.4 Adjusting installation position of tail light
  204
• 4.5 Removing and installing tail light cluster
  205
• 4.6 Removing and installing tail light bulb M2/M4
  205
• 4.7 Removing and installing rear fog light bulb L46/L47
  206
• 4.8 Removing and installing brake and tail light bulb M21/M22
  206
• 4.9 Removing and installing reversing light bulb
  206
• 4.10 Removing and installing turn signal bulb
  206
• 5 High-level brake light
  207
• 5.1 Assembly overview – high-level brake light
  207
• 5.2 Removing and installing high-level brake light
  208
• 6 Number plate light
  212
• 6.1 Removing and installing number plate light X4/X5
  212
• 6.2 Removing and installing bulb for number plate ligt X4/X5
  214
• 7 Entry and start authorisation system
  215
• 7.1 Overview of fitting locations - entry and start authorisation system
  215
• 7.2 Overview of fitting locations - keyless entry system
  217
• 7.3 Removing and installing interface for entry and start system J965
  220
• 7.4 Removing and installing door exterior handle contact sensor G415/G416
  222
• 7.5 Removing and installing contact sensor for rear exterior door handle G417/G418
  222
• 7.6 Removing and installing interior aerial 1 for entry and start system R138
  222
• 7.7 Removing and installing interior aerial 2 for entry and start system R139
  223
• 7.8 Removing and installing driver side aerial for entry and start system R134
  224
• 7.10 Removing and installing rear bumper aerial for entry and start system R136
  225
• 7.12 Removing and installing rear entry and start authorisation aerial R165/R166
  226
• 7.13 Removing and installing rear lid power opening control unit J938
  226
• 7.14 Removing and installing rear lid power opening sender G750/G760
  227
• 8 Steering column switch module
  228
• 8.1 Assembly overview - steering column switch module
  228
• 8.2 Removing and installing steering column switch module
  230
• 8.3 Removing and installing steering column electronics control unit J527
  235
• 8.4 Removing and installing turn signal switch E2
  241
• 8.5 Removing and installing intermittent wiper switch E22
  244
• 8.6 Removing and installing immobiliser reader coil D2
  244
• 8.7 Removing and installing base for steering column combination switch
  244
• 9 Parking aid
  246
• 9.1 Assembly overview – parking aid
  246
• 9.2 Removing and installing parking aid control unit J446
  250
• 9.3 Removing and installing front parking aid warning buzzer H22
  253
• 9.4 Removing and installing rear parking aid warning buzzer H15
  254
• 9.5 Removing and installing front parking aid senders
  255
• 9.6 Removing and installing rear parking aid senders
  256
• 10 Park assist steering
  258
• 10.1 Assembly overview - park assist steering
  258
• 10.2 Removing and installing park assist steering control unit J791
  260
• 10.3 Removing and installing front senders
  260
• 10.4 Removing and installing rear senders
  261
• 11 Automatic headlight range control
  263
• 11.1 Assembly overview - automatic headlight range control
  263
• 11.2 Removing and installing cornering light and headlight range control unit J745
  265
• 12 Towing bracket
  268
• 12.1 Assembly overview - towing bracket socket
  268
• 12.2 Trailer socket U10
  268
• 12.3 Removing and installing trailer detector control unit J345
  269
• Lights, bulbs, switches - interior
  271
• 1 Lights
  272
• 1.1 Overview of fitting locations - lights in dash panel
  273
• 1.2 Overview of fitting locations - lights in front doors
  273
• 1.3 Overview of fitting locations - lights in rear doors
  274
• 1.4 Overview of fitting locations - lights in centre console
  275
• 1.5 Overview of fitting locations - lights in luggage compartment
  276
• 1.6 Overview of fitting locations - lights in roof trim
  278
• 1.7 Removing and installing glove compartment light W6
  280
• 1.8 Replacing bulb for glove compartment light W6
  281
• 1.9 Removing and installing front footwell light K268/K269
  282
• 1.10 Removing and installing front footwell illumination bulb L151/L152
  283
• 1.11 Removing and installing Central locking SAFELOCK function warning lamp K133
  283
• 1.12 Removing and installing light 2 for front door background lighting L203/L204
  284
• 1.13 Removing and installing front entry light W31/W32
  285
• 1.14 Removing and installing door warning lamp W30/W36
  287
• 1.15 Removing and installing light 1 for rear door background lighting L201/L202
  287
• 1.16 Removing and installing rear entry light W33/W34
  288
• 1.17 Removing and installing rear door warning lamp W37/W38
  288
• 1.18 Removing and installing light 1 for front door background lighting L199/L200
  288
• 1.19 Removing and installing bulb for background lighting in rear door L166/L167
  289
• 1.20 Removing and installing interior door handle illumination bulb L146/L147
  289
• 1.21 Removing and installing light for rear interior door handle illumination L221/L222
  290
• 1.22 Removing and installing lights for dashboard background lighting L229/L230
  290
• 1.23 Removing and installing selector lever position display Y26
  290
• 1.24 Removing and installing luggage compartment light W3
  291
• 1.25 Removing and installing illuminated vanity mirror W20/W14
  293
• 1.26 Removing and installing bulb for front interior light W1
  294
• 1.27 Removing and installing bulb for rear interior light W43
  296
• 1.28 Removing and installing bulb for front reading light W13/W19
  298
• 1.29 Removing and installing bulb for rear reading light W11/W12
  298
• 1.30 Renewing bulb of rear interior light W47/W48
  298
• 2 Controls
  302
• 2.1 Overview of fitting locations - controls in dash panel
  303
• 2.2 Overview of fitting locations - controls in front doors
  305
• 2.3 Overview of fitting locations - controls in rear doors
  306
• 2.4 Overview of fitting locations - controls in centre console
  306
• 2.5 Overview of fitting locations - controls in luggage compartment
  307
• 2.6 Overview of fitting locations - controls in roof trim
  308
• 2.7 Removing and installing rotary light switch EX1
  309
• 2.8 Removing and installing headlight range control regulator E102
  311
• 2.9 Removing and installing rear roller blind switch E149
  311
• 2.10 Removing and installing TCS and ESP button E256
  311
• 2.11 Removing and installing parking aid button E266
  311
• 2.12 Removing and installing steering wheel heater button E522
  311
• 2.13 Removing and installing sport program button E541
  312
• 2.14 Removing and installing park assist steering button E581
  312
• 2.15 Removing and installing button for electric drive E656
  312
• 2.16 Removing and installing Start/Stop operation button E693
  312
• 2.17 Removing and installing driving mode selection button E735
  312
• 2.18 Removing and installing centre switch module in dash panel EX22
  312
• 2.19 Removing and installing switch module in centre console EX23/EX30
  313
• 2.20 Removing and installing hazard warning light switch EX3
  315
• 2.21 Removing and installing buttons for seat heating E653/E654
  315
• 2.22 Removing and installing glove compartment light switch E26
  315
• 2.23 Removing and installing exterior mirror adjuster EX11
  316
• 2.24 Removing and installing operating unit for window regulator in driver door E512
  317
• 2.25 Removing and installing front passenger side window regulator button E716
  317
• 2.27 Removing and installing rear lid remote release button E233
  319
• 2.28 Removing and installing fuel tank flap release button E319
  320
• 2.30 Removing and installing door contact switch F2/F3
  322
• 2.31 Removing and installing rear window regulator button E711/E713
  322
• 2.32 Removing and installing rear door contact switches F10/F11
  323
• 2.34 Removing and installing starter button E378
  324
• 2.35 Removing and installing rear lid warning buzzer H32
  324
• 2.36 Removing and installing rear lid contact switch
  325
• 2.37 Removing and installing rear lid closure button E574
  325
• 2.38 Removing and installing electric hinged tow coupling attachment button E474
  326
• 2.39 Removing and installing vanity mirror contact switch F147/F148
  328
• 2.40 Removing and installing sunroof button E325
  328
• 2.41 Removing and installing front interior light WX1
  329
• 2.42 Removing and installing rear interior light WX2
  330
• 2.43 Removing and installing front right reading light button E634
  332
• 3 Anti-theft alarm system
  333
• 3.1 Assembly overview - interior monitor
  333
• 3.2 Removing and installing alarm horn H12
  334
• 3.3 Removing and installing anti-theft alarm sensor G578
  335
• 4 Lane change assist
  337
• 4.1 Assembly overview - lane change assist
  337
• 4.3 Removing and installing lane change assist control unit J769/J770
  339
• 4.4 Calibrating lane change assist
  341
• 5 Front camera for driver assist systems
  350
• 5.1 Removing and installing front camera for driver assist systems
  350
• 6 Cigarette lighter, socket
  351
• 6.1 Assembly overview - DC/AC converter with socket, 12 V-230 V
  351
• 6.2 Removing and installing cigarette lighter U1
  352
• 6.3 Removing and installing socket illumination bulb L42
  352
• 6.4 Removing and installing rear cigarette lighter illumination bulb L32
  352
• 6.5 Removing and installing electric socket U
  352
• 6.6 Removing and installing DC/AC converter with socket, 12 V-230 V U13
  352
• Wiring
  355
• 1 Relay carriers, fuse holders, electronics boxes
  355
• 1.1 Overview of fitting locations - relay carriers, fuse holders, E-boxes
  355
• 1.2 Removing and installing electronics box (E-box)
  360
• 1.3 Removing and installing relay and fuse holder in electronics box
  363
• 1.4 Removing and installing relay and fuse carrier behind dash panel
  365
• 1.5 Removing and installing main fuse holder
  368
• 2 Select Control units
  372
• 2.1 Overview of fitting locations - control units
  372
• 2.2 Assembly overview - control units
  373
• 2.3 Assembly overview - data bus diagnostic interface
  375
• 2.4 Assembly overview - special vehicle control unit and voltage stabiliser
  376
• 2.5 Removing and installing onboard supply control unit J519
  377
• 2.6 Removing and installing data bus diagnostic interface J533
  381
• 2.7 Removing and installing bracket for onboard supply control unit J519
  382
• 2.8 Renewing bracket for onboard supply control unit J519
  385
• 2.9 Removing and installing parking aid control unit J446/park assist steering control unit J791
  385
• 2.10 Removing and installing rear lid control unit J605
  386
• 2.11 Removing and installing special vehicle control unit J608
  388
• 2.12 Removing and installing bracket for special vehicle control unit J608
  389
• 3 Connectors
  391
• 3.1 Repairing electrical wiring harnesses and plug-in connections
  391
• 4 Releasing and dismantling connector housings
  392
• 5 Repairing aerial wires
  393
• 6 Fibre optic cables
  394
• 7 Vehicle diagnosis, testing and information systems
  395