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
• 1.3 Application notes and safety information for LED headlights
  1
• 2 Repair instructions
  2
• 2.1 Rules for cleanliness
  2
• 2.2 General information
  2
• 2.3 Contact corrosion
  2
• 2.4 ESD workplace
  2
• 2.5 Routing and attachment of lines
  3
• 3 Battery
  4
• 3.1 Battery - general notes
  4
• 3.2 Types of battery
  4
• Starter, current supply, CCS
  5
• 1 Battery
  5
• 1.1 Assembly overview – battery
  5
• 1.2 Disconnecting and connecting battery
  7
• 1.3 Removing and installing battery
  9
• 1.4 Renew battery
  13
• 1.5 Checking battery
  13
• 1.6 Charging battery
  13
• 1.7 Removing and installing earth wire with battery monitor control unit J367
  14
• 1.8 Removing and installing battery isolator
  15
• 1.9 Adapting battery monitor control unit J367
  15
• 2 Voltage converter
  16
• 2.1 Assembly overview - voltage converter (48 V/12 V) A7
  16
• 2.2 Removing and installing voltage converter (48 V/12 V) A7
  16
• 3 Storage capacitor
  20
• 3.1 Assembly overview - storage capacitor for 48 V electrical system C31
  20
• 3.2 De-energising 48 V system
  21
• 3.3 Re-energising 48 V system
  21
• 3.4 Removing and installing storage capacitor for 48 V electrical system C31
  21
• 3.5 Removing and installing carrier for storage capacitor
  24
• 4 Jump-start connection
  26
• 4.1 Assembly overview - jump-start connection
  26
• 5 Alternator
  27
• 5.1 Assembly overview - alternator
  27
• 5.2 Removing and installing alternator
  28
• 5.3 Checking alternator
  35
• 5.4 Removing and installing poly V-belt pulley
  36
• 5.5 Removing and installing voltage regulator
  42
• 6 Starter motor
  46
• 6.1 Assembly overview – starter
  46
• 6.2 Removing and installing starter
  47
• 6.3 Checking starter
  54
• 7 Adaptive cruise control
  55
• Gauges, instruments
  56
• 1 Dash panel insert
  56
• 1.1 Assembly overview - dash panel insert
  56
• 1.2 Assembly overview - head-up display
  58
• 1.3 Removing and installing dash panel insert KX2
  60
• 1.4 Removing and installing control unit for head-up display
  63
• 2 Horn
  66
• 2.1 Assembly overview - horn
  66
• 2.2 Removing and installing treble horn H2 and bass horn H7
  66
• 2.3 Removing and installing bracket for horns
  67
• Windscreen wash/wipe system
  69
• 1 Windscreen wiper system
  69
• 1.1 Assembly overview - windscreen wiper system
  69
• 1.2 Moving wipers to service position
  72
• 1.3 Removing and installing wiper blade
  72
• 1.4 Removing and installing wiper arms
  73
• 1.5 Adjusting wiper arms
  74
• 1.6 Removing and installing wiper frame
  76
• 1.7 Deactivating APP function of wiper motor
  77
• 1.8 Removing and installing rain and light sensor
  78
• 2 Windscreen washer system
  83
• 2.1 Assembly overview - windscreen washer system
  83
• 2.2 Removing and installing filler neck for washer fluid reservoir
  85
• 2.3 Removing and installing washer fluid reservoir
  86
• 2.4 Removing and installing windscreen washer fluid level sender
  88
• 2.5 Removing and installing windscreen washer pump
  88
• 2.6 Removing and installing spray jets
  90
• 2.7 Adjusting spray jets
  91
• 3 Rear window wiper system
  92
• 3.1 Assembly overview - rear window wiper system
  92
• 3.2 Removing and installing wiper blade
  93
• 3.3 Removing and installing wiper arm
  93
• 3.4 Adjusting wiper arm
  95
• 3.5 Removing and installing rear window wiper motor V12
  96
• 4 Rear window washer system
  98
• 4.1 Assembly overview - rear window washer system
  98
• 4.2 Removing and installing washer fluid reservoir
  99
• 4.3 Removing and installing rear window washer pump
  100
• 4.4 Removing and installing spray jet
  100
• 4.6 Adjusting spray jet
  101
• 5 Headlight washer system
  102
• 5.1 Assembly overview - headlight washer system
  102
• 5.2 Removing and installing washer fluid reservoir
  104
• 5.3 Removing and installing headlight washer system pump V11
  104
• 5.4 Removing and installing spray jets for camera for night vision system R212
  105
• 5.5 Removing and installing pop-up cylinder
  105
• 6 Washer fluid lines
  108
• 6.1 Repairing washer fluid lines
  108
• Lights, bulbs, switches - exterior
  109
• 1 Headlights
  109
• 1.1 Assembly overview – headlight
  109
• 1.2 Removing and installing headlight
  115
• 1.3 Removing and installing headlight mounting
  116
• 1.4 Adjusting headlights
  117
• 1.5 Adjusting headlight installation position
  118
• 1.6 Removing and installing carrier
  119
• 1.7 Installing repair kit for headlight housing
  119
• 1.8 Converting headlights from driving on right to driving on left
  120
• 1.9 Converting headlights from driving on left to driving on right
  121
• 1.10 Removing and installing headlight range control motor V48/V49
  122
• 1.11 Removing and installing headlight dipped beam bulb
  125
• 1.12 Removing and installing headlight main beam bulb M30/M32
  125
• 1.14 Removing and installing bulbs for cornering light L148/L149
  129
• 1.15 Removing and installing output module 1 for LED headlights A27/A31
  131
• 1.16 Removing and installing light control unit J1018/J1023
  132
• 1.17 Removing and installing headlight fan
  133
• 2 Lights in exterior mirror
  139
• 2.1 Assembly overview - lights in exterior mirror
  139
• 2.2 Removing and installing turn signal
  139
• 2.3 Removing and installing entry light in exterior mirror
  141
• 3 Lights in sill panel moulding
  142
• 3.1 Assembly overview - entry light
  142
• 4 Tail lights
  143
• 4.1 Assembly overview - tail light cluster in body
  143
• 4.2 Assembly overview - tail lights in rear lid
  143
• 4.3 Removing and installing tail light in rear lid
  144
• 4.4 Removing and installing tail light cluster
  146
• 4.5 Adjusting installation position of tail light
  147
• 5 High-level brake light
  149
• 5.1 Assembly overview – high-level brake light
  149
• 5.2 Removing and installing high-level brake light
  149
• 6 Number plate light
  151
• 6.1 Removing and installing number plate light X4/X5
  151
• 6.2 Removing and installing bulb for number plate light X4/X5
  152
• 7 Entry and start authorisation system
  153
• 7.1 Overview of fitting locations - entry and start authorisation system
  153
• 7.2 Overview of fitting locations - keyless entry system
  154
• 7.3 Removing and installing front exterior door handle EX6/EX7
  156
• 7.4 Removing and installing rear exterior door handle EX8/EX9
  156
• 7.5 Removing and installing interior aerial 1 for entry and start system R138
  156
• 7.7 Removing and installing rear entry and start authorisation aerial R165/R166
  157
• 7.8 Removing and installing front entry and start authorisation aerial R376
  158
• 7.9 Removing and installing rear lid power opening control unit J938
  158
• 7.10 Removing and installing rear lid power opening sender G750/G760
  159
• 8 Steering column switch module
  161
• 8.1 Assembly overview - steering column switch module
  161
• 8.2 Removing and installing steering column switch module
  161
• 9 Parking aid
  163
• 10 Park assist steering
  164
• 11 Automatic headlight range control
  165
• 11.1 Assembly overview - automatic headlight range control
  165
• Lights, bulbs, switches - interior
  166
• 1 Lights
  167
• 1.1 Overview of fitting locations - lights in dash panel
  168
• 1.2 Overview of fitting locations - lights in front doors
  170
• 1.3 Overview of fitting locations - lights in rear doors
  171
• 1.4 Overview of fitting locations - lights in centre console
  172
• 1.5 Overview of fitting locations - lights in seats and B-pillars
  173
• 1.6 Overview of fitting locations - lights in luggage compartment
  174
• 1.7 Overview of fitting locations - lights in roof trim
  175
• 1.8 Removing and installing glove compartment light W6
  177
• 1.9 Removing and installing front footwell light K268/K269
  178
• 1.10 Removing and installing Central locking SAFELOCK function warning lamp K133
  178
• 1.11 Removing and installing light for front interior door handle illumination L219/L220
  179
• 1.12 Removing and installing light 1 for front door background lighting L199/L200
  180
• 1.13 Removing and installing bulb for background lighting in front door L158/L179
  181
• 1.14 Removing and installing interior door handle illumination bulb L146/L147
  182
• 1.15 Removing and installing door storage compartment illumination bulb L160/L161
  183
• 1.16 Removing and installing exit warning lamp W111/W112
  184
• 1.17 Removing and installing rear interior door handle illumination bulb L133/L134
  185
• 1.18 Removing and installing light 1 for rear door background lighting L201/L202
  186
• 1.19 Removing and installing bulb for background lighting in rear door L166/L167
  187
• 1.20 Removing and installing lights for dashboard background lighting L229/L230/L231
  188
• 1.21 Removing and installing light for rear interior door handle illumination L221/L222
  188
• 1.22 Removing and installing rear exit warning lamp W113/W114
  189
• 1.23 Removing and installing storage compartment illumination bulb L120
  190
• 1.25 Removing and installing light for cup holder background lighting L232
  192
• 1.26 Removing and installing selector lever position display Y26
  193
• 1.27 Removing and installing rear footwell light W45/W46
  193
• 1.28 Removing and installing left luggage compartment light W18
  193
• 1.29 Removing and installing right luggage compartment light W35
  194
• 1.30 Removing and installing rear lid light W51
  195
• 1.31 Removing and installing illuminated vanity mirror W20/W14
  196
• 2 Controls
  198
• 2.1 Overview of fitting locations - controls in dash panel
  199
• 2.2 Overview of fitting locations - controls in front doors
  201
• 2.3 Overview of fitting locations - controls in rear doors
  202
• 2.4 Overview of fitting locations - controls in centre console
  203
• 2.5 Overview of fitting locations - controls in luggage compartment
  204
• 2.6 Overview of fitting locations - controls in roof trim
  205
• 2.7 Removing and installing light switch E1
  207
• 2.8 Removing and installing steering column adjustment switch E167
  208
• 2.9 Removing and installing park assist steering button E581
  209
• 2.10 Removing and installing switch module EX23/EX30
  209
• 2.11 Removing and installing hazard warning light switch EX3
  210
• 2.12 Removing and installing glove compartment light switch E26
  211
• 2.13 Removing and installing exterior mirror adjuster EX11
  211
• 2.14 Removing and installing operating unit for window regulator in driver door E512
  212
• 2.15 Removing and installing window regulator switch in front passenger door E107
  213
• 2.16 Removing and installing interior locking button E308/E309
  213
• 2.17 Removing and installing operating unit for seat with seat memory E97/E277
  215
• 2.18 Removing and installing rear lid release switch E165
  216
• 2.19 Removing and installing rear window regulator switch in door E52/E54
  217
• 2.21 Removing and installing the starter button E378
  218
• 2.22 Removing and installing operating unit E881/E281
  218
• 2.23 Removing and installing buttons for seat heating E653/E654
  219
• 2.25 Removing and installing rear lid closure button E574
  220
• 2.26 Removing and installing rear lid warning buzzer H32
  222
• 2.27 Removing and installing rear lid contact switch
  222
• 2.28 Removing and installing vanity mirror contact switch F147/F148
  222
• 2.29 Removing and installing sunroof button E325
  222
• 2.30 Removing and installing button 1 for roof roller blind E584
  223
• 2.31 Removing and installing front interior light/reading light
  224
• 2.32 Removing and installing rear interior light/reading light
  226
• 2.33 Removing and installing garage door operating unit E284
  227
• 3 Anti-theft alarm
  229
• 3.1 Assembly overview - interior monitor
  229
• 3.2 Removing and installing alarm horn H12
  229
• 3.3 Removing and installing anti-theft alarm sensor G578
  231
• 4 Lane change assist
  232
• 5 Front camera for driver assist systems
  233
• 6 Towing bracket
  234
• 6.1 Assembly overview - socket, trailer detector control unit
  234
• 6.2 Trailer socket
  234
• 6.3 Removing and installing trailer detector control unit J345
  235
• 7 Cigarette lighter, socket
  237
• 7.1 Overview of fitting locations - DC/AC converter with socket, 12 V-230 V U13
  237
• 7.2 Removing and installing cigarette lighter
  237
• 7.3 Removing and installing bulb for illuminating cigarette lighter
  238
• 7.4 Removing and installing 12 V socket
  238
• 7.5 Removing and installing socket illumination bulb
  238
• 7.6 Removing and installing DC/AC converter with socket, 12 V-230 V U13
  238
• Wiring
  240
• 1 Relay carriers, fuse holders, electronics boxes
  240
• 1.1 Overview of fitting locations - relay carriers, fuse holders, E-boxes
  240
• 1.2 Removing and installing front left relay and fuse carrier
  246
• 1.3 Removing and installing suppression filter C24
  254
• 1.4 Removing and installing wiring junction
  254
• 1.5 Removing and installing dash panel fuse holder
  260
• 1.7 Removing and installing main fuse holder on battery
  265
• 2 Select Control units
  267
• 2.1 Overview of fitting locations - control units
  267
• 2.2 Assembly overview - data bus diagnostic interface
  267
• 2.3 Removing and installing onboard supply control unit J519
  268
• 2.4 Removing and installing bracket for onboard supply control unit J519
  270
• 2.5 Removing and installing convenience system central control unit J393
  270
• 2.6 Removing and installing rear lid control unit J605
  271
• 2.7 Removing and installing garage door operation control unit
  272
• 2.8 Removing and installing data bus diagnostic interface J533
  272
• 3 Connectors
  275
• 3.1 Repairing electrical wiring harnesses and plug-in connections
  275
• 4 Releasing and dismantling connector housings
  276
• 5 Repairing aerial wires
  277
• 6 Fibre optic cables
  278
• 7 Vehicle diagnosis, testing and information systems
  279