Electrical system

Chapter overview

• Technical data
  1
• 1 Safety information
  1
• 1.1 Safety precautions when working on high-voltage vehicles
  1
• 1.2 Safety precautions when working in the vicinity of high-voltage components
  2
• 1.3 Safety measures when working on vehicles with a start/stop system
  2
• 1.5 Operation and safety notes for gas discharge lamps
  3
• 2 Repair instructions
  5
• 2.1 Contact corrosion
  5
• 2.2 Routing and attachment of lines
  5
• 3 Battery
  6
• 3.1 Battery - general notes
  6
• 3.2 Types of battery
  6
• Starter, current supply, CCS
  7
• 1 Battery
  7
• 1.1 Assembly overview - battery
  7
• 1.2 Removing and installing battery
  10
• 1.3 Disconnecting and connecting battery
  18
• 1.4 Removing and installing battery tray
  21
• 1.5 Checking battery
  22
• 1.6 Charging battery
  22
• 1.7 Removing and installing earth wire with battery monitor control unit J367
  22
• 1.8 Adapting battery monitor control unit J367
  25
• 2 Alternator
  26
• 2.1 Assembly overview - alternator
  26
• 2.2 Removing and installing alternator
  28
• 2.3 Checking alternator
  35
• 2.4 Removing and installing poly V-belt pulley
  36
• 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)
  56
• 5 Start/stop system
  57
• 5.1 General description - start/stop system
  57
• 5.2 Overview of fitting locations - start/stop system
  57
• 6 Adaptive cruise control
  59
• 6.1 Overview of fitting locations - adaptive cruise control
  59
• 6.2 Removing and installing automatic distance control unit
  61
• 6.3 Calibrating adaptive cruise control
  69
• Gauges, instruments
  70
• 1 Dash panel insert
  70
• 1.1 Assembly overview - dash panel insert
  70
• 1.2 Removing and installing dash panel insert KX2
  70
• 2 Horn
  73
• 2.1 Assembly overview - horn
  73
• 2.2 Removing and installing treble horn H2 and bass horn H7
  73
• Windscreen wash/wipe system
  75
• 1 Windscreen wiper system
  75
• 1.1 Assembly overview - windscreen wiper system
  75
• 1.2 Moving wipers to service position
  77
• 1.3 Removing and installing wiper blade
  77
• 1.4 Removing and installing wiper arms
  78
• 1.5 Adjusting wiper arms
  79
• 1.6 Removing and installing wiper motor V
  81
• 1.7 Deactivating APP function of wiper motor
  82
• 1.8 Removing and installing rain and light sensor
  83
• 2 Windscreen washer system
  87
• 2.1 Assembly overview - windscreen washer system
  87
• 2.2 Removing and installing washer fluid reservoir
  92
• 2.3 Removing and installing windscreen washer fluid level sender
  96
• 2.4 Removing and installing windscreen washer pump
  97
• 2.5 Removing and installing washer jets
  99
• 2.6 Adjusting spray jets
  100
• 3 Rear window wiper system
  101
• 3.1 Assembly overview - rear window wiper system
  101
• 3.2 Removing and installing wiper blade
  102
• 3.3 Removing and installing wiper arm
  102
• 3.4 Adjusting wiper arm
  103
• 3.5 Removing and installing rear window wiper motor V12
  104
• 4 Rear window washer system
  106
• 4.1 Assembly overview - rear window washer system
  106
• 4.2 Removing and installing washer fluid reservoir
  109
• 4.3 Removing and installing rear window washer pump
  109
• 4.4 Removing and installing spray jet
  110
• 4.5 Adjusting spray jet
  111
• 5 Headlight washer system
  112
• 5.1 Assembly overview - headlight washer system
  112
• 5.2 Removing and installing washer fluid reservoir
  114
• 5.3 Removing and installing headlight washer system pump V11
  114
• 5.4 Removing and installing pop-up cylinder
  116
• 5.5 Removing and installing washer jets
  119
• 5.6 Adjusting spray jets
  119
• 6 Washer fluid lines
  120
• 6.1 Repairing washer fluid lines
  120
• Lights, bulbs, switches - exterior
  121
• 1 Headlights
  122
• 1.1 Assembly overview - headlight
  122
• 1.2 Removing and installing headlight
  137
• 1.3 Adjusting headlights
  141
• 1.4 Adjusting headlight installation position
  141
• 1.5 Removing and installing front turn signal bulb M5 / M7
  143
• 1.6 Installing repair kit for headlight housing
  145
• 1.7 Converting headlights from driving on right to driving on left
  150
• 1.8 Converting headlights from driving on left to driving on right
  152
• 1.9 Removing and installing headlight range control motor V48 / V49
  154
• 1.10 Removing and installing dipped beam bulb
  160
• 1.11 Removing and installing headlight main beam bulb M30 / M32
  165
• 1.12 Removing and installing gas discharge bulb L13 / L14
  169
• 1.13 Removing and installing side light bulb M1 / M3
  171
• 1.14 Removing and installing daytime running light bulb L174 / L175
  171
• 1.15 Removing and installing LED modules for daytime running light and side light L176 / L177
  173
• 1.16 Removing and installing dip beam screen motor V294 / V295
  174
• 1.17 Removing and installing bulbs for cornering light L148 / L149
  174
• 1.18 Removing and installing gas discharge bulb control unit J343 / J344
  175
• 1.19 Removing and installing output module for headlight J667 / J668
  176
• 1.20 Removing and installing control unit for daytime running light and side light J860 / J861
  177
• 1.21 Removing and installing output module 2 for headlights, »R«
  178
• 1.22 Removing and installing output module 1 for LED headlight A31 / A27
  179
• 1.23 Removing and installing control motor sender for VARILIS headlight G695 / G696
  180
• 1.24 Removing and installing control motor for VARILIS headlight V446 / V447
  181
• 1.25 Removing and installing swivel module position sensor G474 / G475
  181
• 1.26 Removing and installing dynamic cornering light control motor V318 / V319
  181
• 2 Fog lights
  182
• 2.1 Assembly overview - fog lights
  182
• 2.2 Removing and installing fog light
  183
• 2.3 Removing and installing fog light bulb L22 / L23
  185
• 3 Lights in exterior mirror
  186
• 3.1 Assembly overview - lights in exterior mirror
  186
• 3.2 Removing and installing turn signal
  187
• 3.3 Removing and installing entry light in exterior mirror
  188
• 4 Tail lights
  190
• 4.1 Assembly overview - tail lights in body
  190
• 4.2 Assembly overview - tail lights in rear lid
  193
• 4.3 Removing and installing tail light in rear lid
  194
• 4.4 Adjusting installation position of tail light
  195
• 4.5 Removing and installing tail light cluster
  196
• 4.6 Removing and installing tail light bulb M2 / M4
  197
• 4.7 Removing and installing rear fog light bulb L46 / L47
  198
• 4.8 Removing and installing brake and tail light bulb M21 / M22
  199
• 4.9 Removing and installing reversing light bulb
  200
• 4.10 Removing and installing turn signal bulb
  201
• 5 High-level brake light
  203
• 5.1 Assembly overview - high-level brake light
  203
• 5.2 Removing and installing high-level brake light
  204
• 6 Number plate light
  207
• 6.1 Removing and installing number plate light X4 / X5
  207
• 6.2 Removing and installing bulb for number plate light X4 / X5
  207
• 7 Entry and start authorisation system
  209
• 7.1 Overview of fitting locations - entry and start authorisation system
  209
• 7.2 Overview of fitting locations - keyless entry system
  212
• 7.3 Removing and installing interface for entry and start system J965
  215
• 7.4 Removing and installing door exterior handle contact sensor G415 / G416
  216
• 7.5 Removing and installing interior aerial 1 for entry and start authorisation R138
  217
• 7.6 Removing and installing driver side aerial for entry and start system R134
  217
• 7.9 Removing and installing rear bumper aerial for entry and start system R136
  218
• 8 Steering column switch module
  219
• 8.1 Assembly overview - steering column switch module
  219
• 8.2 Removing and installing lock cylinder
  221
• 8.3 Removing and installing ignition key withdrawal lock solenoid N376
  223
• 8.4 Removing and installing ignition/starter switch
  224
• 8.5 Removing and installing steering column switch module
  225
• 8.6 Removing and installing steering column electronics control unit J527
  230
• 8.7 Removing and installing turn signal switch E2
  235
• 8.8 Removing and installing cruise control system switch E45
  237
• 8.9 Removing and installing intermittent wiper switch E22
  237
• 8.10 Removing and installing immobiliser reader coil D2
  237
• 8.11 Removing and installing steering lock housing
  238
• 9 Parking aid
  240
• 9.1 Assembly overview – parking aid
  240
• 9.2 Removing and installing parking aid control unit J446
  244
• 9.3 Removing and installing front parking aid warning buzzer H22
  246
• 9.4 Removing and installing rear parking aid warning buzzer H15
  247
• 9.5 Removing and installing front parking aid senders
  248
• 9.6 Removing and installing rear parking aid senders
  249
• 10 Park assist steering
  250
• 10.1 Assembly overview - park assist steering
  250
• 10.2 Removing and installing control unit
  251
• 10.3 Removing and installing front senders
  251
• 10.4 Removing and installing rear senders
  252
• 11 Automatic headlight range control
  253
• 11.1 Assembly overview - automatic headlight range control
  253
• 12 Towing bracket
  258
• 12.1 Assembly overview - towing bracket socket
  258
• 12.2 Trailer socket U10
  258
• 12.3 Removing and installing trailer detector control unit J345
  259
• 13 Blind Spot Monitor
  260
• 13.1 Assembly overview - blind spot monitor
  260
• 13.2 Removing and installing warning lamp for Blind Spot Monitor K303/K304
  261
• 13.3 Removing and installing Blind Spot Monitor control unit J1086/J1087
  261
• 13.4 Calibrating Blind Spot Monitor
  262
• Lights, bulbs, switches - interior
  269
• 1 Lights
  270
• 1.1 Overview of fitting locations - lights in dash panel
  270
• 1.2 Overview of fitting locations - lights in front doors
  272
• 1.3 Overview of fitting locations - lights in rear doors
  273
• 1.4 Overview of fitting locations - lights in centre console
  274
• 1.5 Overview of fitting locations - lights in luggage compartment
  275
• 1.6 Overview of fitting locations - lights in roof trim
  276
• 1.7 Removing and installing glove compartment light W6
  276
• 1.8 Replacing bulb for glove compartment light W6
  277
• 1.9 Removing and installing front footwell light K268 / K269
  278
• 1.10 Removing and installing front footwell illumination bulb L151 / L152
  278
• 1.11 Removing and installing Central locking SAFELOCK function warning lamp K133
  279
• 1.12 Removing and installing reflectors in door
  280
• 1.13 Removing and installing entry light W92 / W93
  281
• 1.15 Removing and installing light for door ambient lighting W86 / W87
  282
• 1.16 Removing and installing light 2 for door background lighting W97 / W98
  282
• 1.17 Removing and installing selector lever position display Y26
  283
• 1.18 Removing and installing luggage compartment light W3
  283
• 1.19 Removing and installing illuminated vanity mirror W20 / W14
  284
• 1.20 Removing and installing bulb for front interior light W1
  285
• 1.21 Removing and installing bulb for rear interior light W43
  287
• 1.22 Removing and installing bulb for rear reading light W11 / W12
  289
• 1.23 Removing and installing LED for ambient lighting
  289
• 2 Controls
  291
• 2.1 Overview of fitting locations - controls in dash panel
  292
• 2.2 Overview of fitting locations - controls in front doors
  294
• 2.3 Overview of fitting locations - controls in rear doors
  295
• 2.4 Overview of fitting locations - controls in centre console
  296
• 2.5 Overview of fitting locations - controls in luggage compartment
  297
• 2.6 Overview of fitting locations - controls in roof trim
  298
• 2.7 Removing and installing rotary light switch EX1
  299
• 2.8 Removing and installing headlight range control regulator E102
  300
• 2.9 Removing and installing driving mode selection button E735
  300
• 2.10 Removing and installing Start/Stop operation button E693
  300
• 2.11 Removing and installing TCS and ESP button E256
  300
• 2.12 Removing and installing parking aid button E266
  300
• 2.13 Removing and installing park assist steering button E581
  301
• 2.14 Removing and installing driving mode selection button E735
  301
• 2.15 Removing and installing switch module in centre console EX23 / EX30
  301
• 2.16 Removing and installing hazard warning light switch EX3
  303
• 2.17 Removing and installing buttons for seat heating E653 / E654
  303
• 2.18 Removing and installing glove compartment light switch E26
  303
• 2.19 Removing and installing exterior mirror adjuster EX11
  304
• 2.20 Removing and installing operating unit for window regulator in driver door E512
  305
• 2.21 Removing and installing front passenger side window regulator button E716
  306
• 2.22 Removing and installing driver side interior locking button for central locking system E308
  306
• 2.23 Removing and installing fuel tank flap release button E319
  307
• 2.25 Removing and installing door contact switch F2 / F3
  309
• 2.26 Removing and installing rear window regulator switch in door E52 / E54
  309
• 2.27 Removing and installing rear door contact switches F10 / F11
  310
• 2.29 Removing and installing the starter button E378
  310
• 2.30 Removing and installing rear lid contact switch for anti-theft alarm F123
  311
• 2.31 Removing and installing vanity mirror contact switch F147 / F148
  311
• 2.32 Removing and installing sunroof button E325
  311
• 2.33 Removing and installing front interior light/reading light
  312
• 2.34 Removing and installing rear interior light/reading light
  313
• 2.35 Removing and installing front right reading light button E634
  314
• 3 Anti-theft alarm
  315
• 3.1 Assembly overview - interior monitor
  315
• 3.2 Removing and installing alarm horn H12
  316
• 3.3 Removing and installing anti-theft alarm sensor G578
  317
• 4 Front camera for assist systems
  320
• 4.1 Removing and installing front camera for driver assist systems
  320
• 5 Cigarette lighter, socket
  321
• 5.1 Removing and installing cigarette lighter U1
  321
• 5.2 Removing and installing socket illumination bulb L42
  321
• 5.3 Removing and installing rear cigarette lighter illumination bulb L32
  321
• 5.4 Removing and installing electric socket U
  321
• Wiring
  322
• 1 Relay carriers, fuse holders, electronics boxes
  322
• 1.1 Overview of fitting locations - relay carriers, fuse holders, E-boxes
  322
• 1.2 Removing and installing electronics box (E-box)
  326
• 1.3 Removing and installing relay and fuse holder in electronics box
  328
• 1.4 Removing and installing relay and fuse carrier behind dash panel
  330
• 1.5 Removing and installing fuse holder, battery
  332
• 2 Control units
  333
• 2.1 Overview of fitting locations - control units
  333
• 2.2 Assembly overview - control units
  337
• 2.3 Assembly overview - data bus diagnostic interface
  339
• 2.4 Removing and installing onboard supply control unit J519
  339
• 2.5 Removing and installing data bus diagnostic interface J533
  342
• 2.6 Removing and installing bracket for onboard supply control unit J519
  343
• 2.7 Renewing bracket for onboard supply control unit J519
  345
• 3 Connectors
  347
• 3.1 Repairing electrical wiring harnesses and plug-in connections
  347
• 4 Releasing and dismantling connector housings
  348
• 5 Repairing aerial wires
  349
• 6 Fibre optic cables
  350
• 7 Vehicle diagnosis, testing and information systems
  351