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 Operation and safety notes for gas discharge lamps
  2
• 1.4 Safety precautions when working on a high-voltage system
  3
• 1.5 Safety precautions when working in the vicinity of high-voltage components
  4
• 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
• 4 Hazard classification of high-voltage system
  7
• Starter, current supply, CCS
  8
• 1 Battery
  8
• 1.1 Assembly overview – battery
  8
• 1.2 Checking battery
  9
• 1.3 Charging battery
  9
• 1.4 Disconnecting and connecting battery
  10
• 1.5 Removing and installing battery
  14
• 1.6 Removing and installing battery partition
  19
• 1.7 Removing and installing battery tray
  20
• 1.8 Removing and installing battery isolator
  21
• 1.9 Removing and installing earth wire with battery monitor control unit J367
  22
• 1.10 Adapting battery monitor control unit J367
  23
• 2 Alternator
  25
• 2.1 Assembly overview - alternator
  25
• 2.2 Removing and installing alternator
  26
• 2.3 Checking alternator
  30
• 2.4 Checking poly V-belt
  30
• 2.5 Removing and installing poly V-belt pulley
  31
• 2.6 Removing and installing voltage regulator
  37
• 3 Starter motor
  40
• 3.1 Assembly overview – starter
  40
• 3.2 Checking starter
  41
• 3.3 Removing and installing starter
  41
• 4 Cruise control system (CCS)
  52
• 5 Start/stop system
  53
• 5.1 General description - start/stop system
  53
• 5.2 Overview of fitting locations - start/stop system
  53
• 5.3 Removing and installing voltage stabiliser
  54
• 6 Adaptive cruise control
  57
• 6.1 Overview of fitting locations - adaptive cruise control
  57
• 6.2 Removing and installing automatic distance control unit
  57
• 6.3 Removing and installing trim for radar sensor
  59
• 6.4 Calibrating adaptive cruise control
  59
• Gauges, instruments
  60
• 1 Dash panel insert
  60
• 1.1 Assembly overview - dash panel insert
  60
• 1.2 Removing and installing dash panel insert KX2
  60
• 1.3 Removing and installing ambient temperature sensor
  63
• 2 Clock
  64
• 2.1 Removing and installing clock
  64
• 3 Horn
  65
• 3.1 Assembly overview - horn
  65
• 3.2 Removing and installing horn or dual tone horn H1/bass horn H7
  65
• 4 Tachograph “DTCO 1381”
  67
• 4.1 General description - tachograph “DTCO 1381”
  67
• 4.2 Overview of fitting locations - tachograph “DTCO 1381”
  69
• 4.3 Removing and installing tachograph “DTCO 1381”
  70
• 4.4 Messages displayed on tachograph “DTCO 1381”
  71
• 4.5 Connector pin assignment - tachograph “DTCO 1381”
  73
• 4.6 Removing and installing tachograph sender G75
  75
• Windscreen wash/wipe system
  83
• 1 Windscreen wiper system
  83
• 1.1 Assembly overview - windscreen wiper system
  83
• 1.2 Moving wipers to service position
  84
• 1.3 Removing and installing wiper blade
  85
• 1.4 Removing and installing wiper arms
  86
• 1.5 Adjusting wiper arms
  88
• 1.6 Removing and installing wiper frame with linkage and wiper motor V
  89
• 1.7 Renewing wiper motor
  91
• 1.8 Removing and installing rain and light sensor
  96
• 2 Windscreen washer system
  100
• 2.1 Assembly overview - windscreen washer system
  100
• 2.2 Removing and installing filler pipe for washer fluid reservoir
  101
• 2.3 Removing and installing washer fluid reservoir
  103
• 2.4 Removing and installing windscreen washer fluid level sender
  106
• 2.5 Removing and installing windscreen washer pump
  106
• 2.6 Removing and installing spray jets
  107
• 2.7 Adjusting spray jets
  108
• 3 Rear window wiper system
  110
• 3.1 Assembly overview - rear window wiper system
  110
• 3.2 Removing and installing wiper blade
  112
• 3.3 Removing and installing wiper arm
  114
• 3.4 Adjusting wiper arm
  116
• 3.5 Removing and installing rear window wiper motor V12
  118
• 4 Rear window washer system
  124
• 4.1 Assembly overview - rear window washer system
  124
• 4.2 Removing and installing washer fluid reservoir
  127
• 4.3 Removing and installing rear window washer pump
  127
• 4.4 Removing and installing spray jet
  127
• 4.5 Adjusting spray jet
  129
• 5 Headlight washer system
  130
• 5.1 Assembly overview - headlight washer system
  130
• 5.2 Removing and installing washer fluid reservoir
  132
• 5.3 Removing and installing headlight washer system pump V11
  132
• 5.4 Removing and installing pop-up cylinder
  133
• 5.5 Removing and installing spray jets
  135
• 5.6 Adjusting spray jets
  135
• 5.7 Bleeding headlight washer system
  135
• 6 Washer fluid lines
  136
• 6.1 Washer fluid line hose couplings
  136
• 6.2 Repairing washer fluid lines
  136
• Lights, bulbs, switches - exterior
  137
• 1 Headlights
  137
• 1.1 Assembly overview – headlight
  137
• 1.2 Removing and installing headlight
  142
• 1.3 Adjusting headlights
  145
• 1.4 Adjusting headlight installation position
  145
• 1.5 Removing and installing front turn signal bulb M5/M7
  147
• 1.6 Installing repair kit for headlight housing
  151
• 1.7 Converting headlights from driving on right to driving on left
  151
• 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 headlight dipped beam bulb M29/M31
  159
• 1.11 Removing and installing headlight main beam bulb M30/M32
  164
• 1.12 Removing and installing side light bulb M1/M3
  168
• 1.13 Removing and installing daytime running light bulb L174/L175
  171
• 1.14 Removing and installing output module for headlight J667/J668
  178
• 1.15 Removing and installing output module 1 for LED headlights A27/A31
  181
• 1.16 Removing and installing LED headlight fan
  182
• 1.17 Fine adjustment of LED modules - LED headlights
  184
• 2 Fog lights
  187
• 2.1 Assembly overview - fog lights
  187
• 2.2 Removing and installing fog light
  187
• 2.3 Removing and installing fog light bulb L22/L23
  188
• 2.4 Removing and installing static cornering light bulb
  190
• 2.5 Adjusting fog lights
  190
• 3 Turn signal repeater
  191
• 3.1 Removing and installing turn signal repeater
  191
• 3.2 Removing and installing turn signal repeater bulb M18/M19
  192
• 4 Lights in sill panel moulding
  194
• 4.1 Removing and installing entry light
  194
• 4.2 Removing and installing bulb for entry light
  195
• 5 Tail lights
  198
• 5.1 Assembly overview – tail lights
  198
• 5.2 Removing and installing bulb carrier
  202
• 5.3 Removing and installing tail light cluster
  205
• 5.4 Removing and installing tail light bulb M2/M4
  208
• 5.5 Removing and installing rear fog light bulb L46/L47
  211
• 5.6 Removing and installing brake light bulb M9/M10
  215
• 5.7 Removing and installing reversing light bulb M16/M17
  219
• 5.8 Removing and installing turn signal bulb M6/M8
  223
• 6 High-level brake light
  229
• 6.1 Removing and installing high-level brake light
  229
• 6.2 Removing and installing high-level brake light
  232
• 7 Number plate light
  233
• 7.1 Removing and installing number plate light X4/X5
  233
• 7.2 Removing and installing bulb for number plate light X4/X5
  236
• 8 Steering column switch module
  239
• 8.1 Assembly overview - steering column switch module
  239
• 8.2 Removing and installing airbag coil connector and return ring with slip ring F138
  240
• 8.3 Removing and installing steering column combination switch
  241
• 8.4 Removing and installing steering column switch module
  242
• 8.5 Removing and installing ignition/starter switch
  244
• 8.6 Removing and installing lock cylinder
  246
• 8.7 Removing and installing steering lock housing
  248
• 9 Parking aid
  251
• 9.1 Assembly overview – parking aid
  251
• 9.2 Removing and installing parking aid control unit J446
  253
• 9.3 Removing and installing front parking aid warning buzzer H22
  254
• 9.4 Removing and installing warning buzzer 2 for rear parking aid H31
  256
• 9.5 Adjusting volume and frequency of warning buzzer 2 for rear parking aid H31
  256
• 9.6 Removing and installing front parking aid senders
  257
• 9.7 Removing and installing rear parking aid senders
  258
• 10 Automatic headlight range control
  260
• 10.1 Removing and installing headlight range control unit
  260
• 11 Towing bracket
  261
• 11.1 Assembly overview - towing bracket socket
  261
• 11.2 Trailer socket U10
  261
• 11.3 Removing and installing trailer socket U10
  262
• 11.4 Removing and installing trailer detector control unit J345
  264
• Lights, bulbs, switches - interior
  266
• 1 Lights
  266
• 1.1 Overview of fitting locations - lights in dash panel
  266
• 1.2 Overview of fitting locations - lights in luggage compartment
  267
• 1.3 Overview of fitting locations - lights in roof trim
  268
• 1.4 Removing and installing glove compartment light W6
  269
• 1.5 Replacing bulb for glove compartment light W6
  270
• 1.6 Removing and installing front entry light W31/W32
  271
• 1.7 Removing and installing bulb for front entry light W31/W32
  273
• 1.8 Removing and installing rear entry light W33/W34
  275
• 1.9 Removing and installing bulb for rear entry light W33/W34
  275
• 1.10 Removing and installing luggage compartment light W3
  276
• 1.11 Removing and installing bulb for luggage compartment light W3
  277
• 1.12 Removing and installing vanity mirror light W20/W14
  277
• 1.13 Removing and installing bulb for illuminated vanity mirror W20/W14
  278
• 1.14 Removing and installing front interior light/reading light
  279
• 1.15 Removing and installing bulb for front interior light/reading light
  283
• 1.16 Removing and installing rear interior light/reading light
  286
• 1.17 Removing and installing bulb for rear interior light/reading light
  291
• 2 Controls
  295
• 2.1 Overview of fitting locations - controls in dash panel
  297
• 2.2 Overview of fitting locations - controls in front doors
  299
• 2.3 Overview of fitting locations - controls in luggage compartment
  300
• 2.4 Overview of fitting locations - controls in roof trim
  300
• 2.5 Removing and installing rotary light switch EX1
  301
• 2.6 Removing and installing regulator for switch and instrument illumination E20
  303
• 2.7 Removing and installing headlight range control regulator E102
  303
• 2.8 Removing and installing Start/Stop operation button E693
  304
• 2.9 Removing and installing TCS and ESP button E256
  304
• 2.10 Removing and installing parking aid button E266
  304
• 2.12 Removing and installing heated rear window switch E15
  305
• 2.13 Removing and installing tyre pressure monitor display button E492
  305
• 2.14 Removing and installing heated windscreen button E627
  306
• 2.15 Removing and installing rear differential lock switch E121
  306
• 2.16 Removing and installing hill descent control button E618
  306
• 2.17 Removing and installing sliding door button E442
  307
• 2.18 Removing and installing button to deactivate sliding door E443
  307
• 2.19 Removing and installing interior light switch (taxi) E115
  307
• 2.20 Removing and installing taxi sign switch E138
  307
• 2.21 Removing and installing buttons in centre of dash panel
  308
• 2.22 Removing and installing hazard warning light switch EX3
  309
• 2.23 Removing and installing buttons for seat heating E653/E654
  310
• 2.24 Removing and installing glove compartment light switch E26
  310
• 2.25 Removing and installing mirror adjustment switch E43/E168
  310
• 2.26 Removing and installing operating unit for window regulator in driver door E512
  312
• 2.27 Removing and installing window regulator switch in front passenger door E107
  314
• 2.29 Removing and installing rear lid remote release button E233
  315
• 2.30 Removing and installing door contact switch F2/F3
  316
• 2.31 Removing and installing rear door contact switches F10/F11
  317
• 2.32 Removing and installing release button for rear lid lock cylinder F248
  319
• 2.33 Removing and installing rear lid closure button E574
  319
• 2.34 Removing and installing rear lid warning buzzer H32
  320
• 2.35 Removing and installing rear lid contact switch
  320
• 2.36 Removing and installing vanity mirror contact switch F147/F148
  320
• 2.37 Removing and installing sliding sunroof adjustment regulator E139
  321
• 2.38 Removing and installing front interior light/reading light
  322
• 2.39 Removing and installing rear interior light/reading light
  322
• 2.41 Controls in interior, Business
  325
• 3 Anti-theft alarm
  329
• 3.1 Assembly overview - interior monitor
  329
• 3.2 Removing and installing alarm horn H12
  331
• 3.3 Removing and installing anti-theft and tilt system control unit
  332
• 3.5 Removing and installing deactivation button for vehicle inclination sender
  338
• 4 Immobiliser
  340
• 4.1 General description - immobiliser
  340
• 4.2 Removing and installing immobiliser control unit
  340
• 4.3 Adapting immobiliser control unit
  340
• 4.4 Removing and installing immobiliser reader coil
  340
• 5 Lane change assist
  341
• 5.1 Assembly overview - lane change assist
  341
• 5.3 Removing and installing lane change assist control unit J769/J770
  343
• 5.4 Calibrating lane change assist
  344
• 6 Front camera for driver assist systems
  354
• 7 Cigarette lighter, socket
  355
• 7.1 Overview of fitting locations - DC/AC converter with socket, 12 V-230 V
  355
• 7.2 Assembly overview - DC/AC converter with socket, 12 V-230 V
  356
• 7.3 Assembly overview - cigarette lighter, 12 V socket
  357
• 7.4 Removing and installing cigarette lighter U1
  358
• 7.5 Removing and installing socket illumination bulb L42
  358
• 7.6 Removing and installing rear cigarette lighter illumination bulb L32
  358
• 7.7 Removing and installing electric socket U
  359
• 7.8 Removing and installing DC/AC converter with socket, 12 V-230 V U13
  359
• 7.9 Removing and installing 230 V socket insert
  362
• 7.10 Removing and installing 230 V socket housing
  364
• 7.11 Fuses for AC/DC converter with socket, 12 V-230 V U13
  366
• 8 Controls in interior, Business
  367
• Wiring
  370
• 1 Relay carriers, fuse holders, electronics boxes
  370
• 1.1 Overview of fitting locations - relay carriers, fuse holders, E-boxes
  370
• 1.2 Removing and installing electronics box on left side of engine compartment
  371
• 1.3 Removing and installing coupling station in seat box at front on left
  376
• 1.4 Removing and installing relay carrier and fuse holder in front seat boxes
  377
• 1.5 Removing and installing relay carrier and fuse holder in centre console
  378
• 1.6 Removing and installing coupling station electronics box
  378
• 1.7 Removing and installing relay carrier and fuse holder in electronics box
  378
• 2 Select Control units
  379
• 2.1 Overview of fitting locations - control units
  379
• 2.2 Removing and installing onboard supply control unit J519
  380
• 2.3 Removing and installing data bus diagnostic interface J533
  381
• 2.4 Removing and installing special vehicle control unit J608
  381
• 2.5 Coding special vehicle control unit
  383
• 2.6 Removing and installing rear lid power opening control unit J938
  383
• 3 Connectors
  385
• 3.1 Repairing electrical wiring harnesses and plug-in connections
  385
• 4 Releasing and dismantling connector housings
  386
• 5 Repairing aerial wires
  387
• 6 Fibre optic cables
  388
• 7 Vehicle diagnosis, testing and information systems
  389