Part 2
WM 970919 Removing and installing main wire harness
Removing main wire harness
CAUTION
Damage caused by improper handling of main wire harness.
-> The main wire harness contains all airbag lines, antenna lines and optical waveguides.
-> The main wire harness must therefore not be cut for major repair work and must be replaced complete.
-> If individual wires are damaged, these must be "shut down" (disconnect wires, remove plug-in contacts from plug connections, etc.) and replaced by installing new wires. Lay the new wires along the main wire harness and tie them to it.
Information
Depending on the equipment I No., the installation positions of the audio components in the front luggage compartment differ.
Overview of connectors for front main wire harness, shown on the 911
1. Disconnect plug connection between main wire harness and front-end wire harness, right -1-.
Disconnecting plug connection between front-end wire harness and main wire harness, right
1.1. Release plug connection between front-end wire harness and main wire harness, right -Arrow a- and disconnect -Arrow B-.
1.2. Turn socket 90° clockwise and remove.
2. Pull off connector on fuse box for fan -2-.
Pulling off connector on fuse box for fan
2.1. Unclip fuse box for fan -Arrow A- and lift up and off -Arrow B-.
2.2. Release lid -arrows- and open -Arrow C-.
2.3. Pull off connector on fuse box for fan -Arrow D-.
3. Loosen ground point left -11-.
Loosening ground point
3.1. Screw off fastening nut and remove ground straps.
4. Release plug connection between main wire harness and front-end wire harness, left -12- and disconnect. Unclip connector socket.
5. Release connector on hydraulic unit -13- and pull it off. -> 453019 Removing and installing hydraulic unit - section on "Removing" 453019 Removing and installing hydraulic unit
6. Release connector on brake fluid sender -14- and pull it off.
7. Release connector for tyre pressure monitoring system control unit -15- and pull it off. -> 443419 Removing and installing control unit for tyre pressure monitoring system - section on "Removing" 44341900 Removing and installing control unit for Tyre Pressure Monitoring (TPM)
8. Unclip wire harness for front end control unit -arrow-.
Unclipping wire harness
9. Unclip wire harness to loudspeaker amplifier -Arrows A- and remove adhesive tape -Arrow B-.
Unclipping wire harness to loudspeaker amplifier
10. Unclip wire harness to CD changer/navigation unit -arrows-.
Unclipping wire harness to CD changer/navigation unit
11. Remove grommets -16- left and right.
12. Pull through main wire harness in direction of plenum panel.
13. Disconnect and release ABS wire harness front left and right -17 and 18-. -> 976555 Replacing ABS wire harness - section on "Removing" 976555 Replacing wire harness for anti-lock brake system (ABS)
13.1. Release and disconnect plug connection for wheel sensor at left and right.
13.2. Unscrew fastening screw of connector socket.
13.3. Release rear wire harness.
14. Release and pull off connectors on front antenna for tyre pressure monitoring system -19 and 20- at left and right. -> 443819 Removing and installing antenna for tyre pressure monitoring system - section on "Removing" 44381900 Removing and installing tyre pressure monitoring system antenna
15. Release and pull off connector of switching element for filler flap -21-.
16. Pull off connector from tank filler neck -22-. -> 200719 Removing and installing filler neck - section on "Removing"
Information
Only in the cabriolet.
17. Release connector on rod antenna -23- and pull it off.
18. Unclip wire harness on end plate under windscreen at the three retaining clips -arrow-.
Unclipping wire harness
19. Release connector on GPS antenna -24- and pull it off. -> 911319 Removing and installing GPS antenna - section on "Removing" Service and Repair
20. Release connector on radio antenna -25- and pull it off. -> 914719 Removing and installing radio antenna - section on "Removing" Service and Repair
21. Release connector for vertical sensor -26- and pull it off.
22. Release connector for pressure switch -27- and pull it off. -> 878319 Removing and installing pressure switch - section on "Removing" Service and Repair
Information
Only for vehicles with I number 536
23. Release connector for alarm siren -28- and pull it off. -> 966519 Removing and installing alarm siren - section on "Removing" Service and Repair
24. Release and pull off B+ line -29- from power distributor. -> 978919 Removing and installing power distributor - section on "Removing" 97891900 Removing and installing power distributor
25. Release plug connections for PASM, front left and right -30 und 31- -Arrow a- and disconnect.
Disconnecting PASM plug connection
26. Release and pull off connectors for windscreen washer system spray nozzle, left and right -32 and 33-.
Information
Only for vehicles with TPM.
27. Release and pull off connector on front angle sensor for headlight beam adjustment -34-. -> 947819 Removing and installing front angle sensor for headlight beam adjustment - section on "Removing" 94781900 Removing and installing front angle sensor for headlight range adjustment
28. Release and pull off connector on wiper motor -38-. -> 921519 Removing and installing wiper motor - section on "Removing" 92151900 Removing and installing wiper motor
29. Release and pull off connector on alarm horn -39-. -> 966519 Removing and installing alarm siren - section on "Removing" Service and Repair
30. Undo the four fastening nuts on the battery retaining bracket and remove the battery retaining bracket.
Removing and installing battery retaining bracket
31. Release connector on fuel level sender -40- -Arrow A- and pull it off -Arrow B-.
Pulling off tank connector
32. Unclip wire harness on end plate under windscreen at the two retaining clips -arrow-.
Unclipping wire harness
33. Remove grommets -41- in centre, and on left and right.
34. Pull through main wire harness in direction of interior.
Exposing main wire harness in passenger compartment
1. Loosen seat belt mount at left and right.
Undoing seat belt and fitting
1.1. Press off cap -1- with a screwdriver and unscrew the fastening screw -2-. Remove seat belt with fitting -3- and spacer sleeve -4-.
2. Disengage floor covering at the support and lay it in the vehicle interior.
3. Remove left and right support.
Unlocking locating peg using the removal tool
3.1. Unlock locating peg -1- of the support using the commercially available removal tool Disassembly tool, universal NR.21.
3.2. Unscrew fastening screws -2- and nuts -3- and carefully pull the support up and out of the retaining points.
Unscrewing fastening screws
Removing main wire harness in passenger compartment
Overview of main wire harness for dashboard
Overview of connectors for main wire harness in passenger compartment
1. Disconnect plug connections for main wire harness to rear wire harness -33 and 34-.
Disconnect plug connections for main wire harness to rear wire harness.
1.1. Release plug connections for main wire harness to rear wire harness -arrows A- and disconnect.
2. Disconnect plug connections for main wire harness to engine wire harness -35 and 36-.
Disconnecting plug connections for main wire harness to engine wire harness
2.1. Release plug connections for main wire harness to engine wire harness -arrows A- and disconnect -arrows B-.
2.2. Release sockets for main wire harness -arrows C- and push down from relay carrier -arrows D-.
3. Release connector for rear vertical sensor -37- and pull it off.
4. Release and pull off connector on DME control module -38 and 39-. -> 247019 Removing and installing DME control module - section on "Removing" Service and Repair
5. Loosen ground point in luggage compartment -40-.
Loosening ground point
5.1. Screw off fastening nut and remove ground strap.
6. Release and pull off connector on rear angle sensor for headlight beam adjustment -41-. -> 947919 Angle sensor for rear headlight levelling system - section on "Removing" 94791900 Removing and installing rear angle sensor for headlight levelling system
7. Remove rubber sleeves -42-.
8. Disconnect main wire harness plug connections for rear lid wire harness -47 and 48-.
Disconnecting main wire harness plug connections for rear lid wire harness
8.1. Release main wire harness plug connections for rear lid wire harness -arrows A- and -arrows B- disconnect.
8.2. Release connector sockets for main wire harness -arrows C- and push down from retaining clip -arrows D-.
8.3. Unclip tie-wrap -arrow E-.
9. Disconnect PASM plug connections -49 and 50- at left and right.
Disconnecting PASM plug connection
9.1. Release and disconnect plug connection for wheel sensor at left and right -arrow a-.
10. Release and pull off connector on rear antenna for tyre pressure monitoring system -51 and 52- at left and right. -> 443819 Removing and installing antenna for tyre pressure monitoring system - section on "Removing" 44381900 Removing and installing tyre pressure monitoring system antenna
11. Disconnect and expose ABS wire harness rear on left and right -53 and 54-. -> 976555 Replacing ABS wire harness - section on "Removing" 976555 Replacing wire harness for anti-lock brake system (ABS)
11.1. Release and disconnect plug connection for wheel sensor at left and right.
11.2. Unscrew fastening screw of connector socket.
11.3. Release rear wire harness.
12. Unclip the main wire harness in the area of the rear left spring strut.
Unclipping the main wire harness in the area of the rear left spring strut
13. Pull off connector on front seat-belt tensioner -56 and 57- at left and right. -> 691319 Removing and installing front three-point seat belt with tensioner - section on "Removing" Testing and Inspection Testing and Inspection
14. Unclip main wire harness to the left side wall.
Unclipping main wire harness to the left side wall
14.1. Unclip main wire harness to the left side wall -arrow A-.
14.2. Unclip cable duct to the left side wall -arrow B-.
15. Loosen cable duct to the left side wall.
Loosening cable duct to the left side wall
15.1. Unclip main wire harness to the bottom of the B-pillar -arrow A-.
15.2. Take out cable duct upwards out of the rear wall plate -arrow B-.
16. Release and pull off connector for airbag sensor, centre left and right -58 and 59-. -> 695119 Removing and installing airbag sensor - section on "Removing" 69511900 Removing and installing airbag sensor
17. Release and pull off connector for ParkAssist control unit -60 and 61-. -> 917419 Removing and installing ParkAssist control unit - section on "Removing" Service and Repair
18. Release and pull off connector for rear end convenience systems control unit -62 to 64-. -> 578919 Removing and installing control unit for rear end convenience systems - section on "Removing". Service and Repair
19. Loosen ground point under the driver's seat -65-.
Loosening ground point
19.1. Screw off fastening nut and remove ground straps.
20. Unclip ground point under driver's seat.
Unclipping ground point under driver's seat
21. Release and remove connectors for telephone control unit -66 to 69-. -> 919019 Removing and installing control unit for telephone - section on "Removing" 91901900 Removing and installing control unit for telephone
21.1. Unclip wire harness for telephone control unit.
Unclipping wire harness for telephone control unit
22. Loosen ground point under the passenger's seat -70-.
Loosening ground point
22.1. Screw off fastening nut and remove ground straps.
23. Unclip wire harness at door sill.
Unclipping wire harness at door sill
24. Disconnect the plug connection between main wire harness and wire harness for door, left and right -75 and 76-. -> 973219 Removing and installing wire harness for door - section on "Disconnecting" 97321900 Removing and installing wire harness for door
25. Release and pull off connector for gateway control unit -81-. -> 903519 Removing and installing gateway control unit - section on "Removing" 903519 Removing and installing gateway control unit
26. Release and pull off connectors for KESSY/PAS control unit -82 and 83-. -> 966619 Removing and installing KESSY control unit - section on "Removing" Service and Repair
27. Release and pull off connector for stop light switch -84-. -> 943619 Removing and installing stop light switch - section on "Removing". Service and Repair
28. Release and pull off connector for pedal sensor -85-.
29. Loosen ground point under the unit carrier -92-.
Loosening ground point
29.1. Screw off fastening nut and remove ground straps.
30. Release and pull off connector for tilt sensor control unit -93-. -> 966319 Tilt sensor control unit - section on "Removing" Service and Repair
31. Disconnect plug connections between main wire harness and wire harness for heater/air-conditioning unit -95 and 96-.
Releasing electric plug connection
31.1. Release lower plug connection on heater/air-conditioning unit -arrows a- and unplug.
31.2. Release upper plug connection on heater/air-conditioning unit -arrows a- and unplug.
Releasing plug connection
31.3. Cut tie-wraps (main wire harness to heater/air-conditioning unit wire harness) with side cutters. Remove main wire harness.
Cutting tie-wraps
32. Release and disconnect plug connection for rain sensor -99-. -> 921219 Removing and installing rain sensor - section on "Removing" Service and Repair
33. Disconnect plug connection of make-up mirror, left and right -100 and 101-.
Disconnecting plug connection of make-up mirror
33.1. Unclip plug connection from console -arrow B-.
33.2. Release plug connection -arrow a- and disconnect it -arrows C-.
34. Unclip cable duct at front of roof frame.
Unclipping cable duct at front of roof frame
35. Unclip main wire harness at front of roof frame.
Unclipping main wire harness at front of roof frame
36. Remove main wire harness from A-pillar -area A-.
Removing main wire harness from A-pillar
37. Pull off connector for antenna amplifier, left and right -102 to 106-. -> 918419 Removing and installing antenna amplifier - section on "Removing" Service and Repair
38. Loosen ground points on dashboard bracket.
Loosening ground points on dashboard bracket
38.1. Unscrew fastening nuts and remove ground straps.
39. Unclip length compensation at the steering column.
Unclipping length compensation
39.1. Remove expansion rivet and length compensation.
40. Unclip cable guide on dashboard bracket.
Unclipping cable guide
41. Loosen holder for relay carrier.
Loosening holder for relay carrier
41.1. Unscrew the two fastening screws and remove the relay carrier holder from the dashboard bracket.
42. Loosen main wire harness at left dashboard bracket.
Loosening main wire harness at left dashboard bracket
42.1. Screw off fastening nut and remove fastening screw.
42.2. Unclip main wire harness on cable guide.
43. Loosen main wire harness at right dashboard bracket.
Loosening main wire harness at right dashboard bracket
43.1. Unclip main wire harness on both cable guides.
44. Loosen main wire harness at centre dashboard bracket.
Loosening main wire harness at centre dashboard bracket
44.1. Undo the four tie-wraps and remove main wire harness.