970955 Replacing the wire harness for brake booster
WM 970955 Replacing the wire harness for brake booster
Tools
Technical values
Preliminary work
1. Disconnect battery. -> 2706IN Working instructions after disconnecting the battery Procedures
2. Remove dashboard bracket. -> 701219 Removing and installing dashboard bracket - section on "Removing" 701219 Removing and installing bracket for dashboard
3. Remove heater/air-conditioning unit. -> 851519 Removing and installing heater/air-conditioning unit - section on "Removing" 851519 Removing and Installing Heater/Air-Conditioning Unit
4. Remove the wiper motor. -> 921519 Removing and installing wiper motor - section on "Removing" 921519 Removing and installing wiper motor
5. Remove left and rear trim covers in engine compartment. -> 700219 Removing and reinstalling front cover (engine compartment) - section on "Removing" 700219 Removing and installing front trim (engine compartment)
Removing wire harness for brake booster
Installation position of wire harness for brake booster
1. Remove cover from cable duct.
Removing cover from cable duct
Information
When cutting the wire harness for the brake booster, make sure there is enough length of cable left to join to the new lines.
2. Cut off wire harness for brake booster in area -a-.
Cut off wire harness for brake booster and expose
3. Remove fabric tape and tie-wrap in area -b- and expose the remaining lines.
4. Unscrew ground strap -1- to the centre firewall.
Loosening ground strap at centre firewall
4.1. Unscrew fastening nut on the centre firewall and remove the ground strap with the twist lock -arrow A-.
4.2. Unclip wire harness for brake booster on retaining clip -arrow B-.
5. Pull off connector on reservoir for brake fluid -4-.
Pulling off connector on reservoir for brake fluid
5.1. Release connector on reservoir for brake fluid -arrow A- and pull off -arrow B-.
6. Pull off connector on brake booster -5-.
Pulling off connector on brake booster
6.1. Release connector on brake booster with suitable auxiliary materials (e.g. angled piece of wire) -a- -arrow A- and pull off -arrow B-.
7. Pull off connector on way-sensor (brake assist system) -6-.
Pulling off connector on way-sensor (brake assist system)
7.1. Release connector on way-sensor (brake assist system) with suitable auxiliary materials (e.g. angled piece of wire) -a- -arrow A- and pull off -arrow B-.
8. Pull off pressure sensor connector (brake assist system) -7-.
Pulling off connector on pressure sensor (brake assist system)
8.1. Release connector on pressure sensor (brake assist system) using suitable auxiliary materials (e.g., an angled piece of wire) -a- -arrow A- and pull it off -arrow B-.
9. Open the retaining clip -arrows A- and take out the line -arrow B-.
Loosening the wire harness for brake booster
10. Open both supports (brake assist system) -arrows C- and take out the wire harness for the brake booster -arrow D-.
11. Remove rubber sleeve -8- on the centre firewall.
Removing the rubber sleeve on the centre firewall
11.1. Unclip the wire harness for brake booster on retaining clip from the centre firewall -arrow A-.
11.2. Remove rubber sleeve on the centre firewall in direction of the engine compartment -arrow B- and take out wire harness for brake booster.
Installing the wire harness for brake booster
Installation position of wire harness for brake booster
1. Remove rubber sleeve -8- on the centre firewall.
1.1. Push wire harness for brake booster through from engine compartment in the direction of passenger compartment -arrow A- and fasten the rubber sleeve to the centre firewall.
1.2. Clip the wire harness for brake booster with the retaining clip to the centre firewall -arrow B-.
Fitting rubber sleeve
2. Insert wire harness for brake booster in both supports -arrows A- and close the supports -arrows B-.
Fastening the wire harness for brake booster
3. Insert line in both retaining clips -arrows C- and close the retaining clips -arrows D-.
4. Connect pressure sensor connector (brake assist system) -7-.
Pressure sensor connector (brake assist system) connected
4.1. Insert the pressure sensor connector (brake assist system) until it is felt to engage.
5. Connect way-sensor connector (brake assist system) -6-.
Connecting way-sensor connector (brake assist system)
5.1. Insert the way-sensor connector (brake assist system) until it is felt to engage.
6. Connect connector to brake booster -5-.
Connecting connector to brake booster
6.1. Push connector onto brake booster until it is felt to engage.
7. Connect plug on brake fluid reservoir -4-.
Connecting plug on brake fluid reservoir
7.1. Push on connector for brake fluid reservoir until it is felt to engage.
8. Tighten ground strap -1- to centre firewall.
Fastening ground strap to centre firewall
8.1. Clip the wire harness for brake booster with the retaining clip to the firewall -arrow A-.
8.2. Connect ground strap with twist lock on the threaded bolt to the centre firewall -arrow B- and screw down with the fastening nut. => Tightening torque: 9 Nm (6.5 ftlb.)
Information
Select a place for the joint where there is enough space to join all the lines present.
Do not cut the lines too short in case they have to be laid in a different position if there is insufficient space in the area of the joint.
Information
The electric lines are located in the plenum panel and are thus exposed to the highest demands.
The greatest care must be used in the individual work steps for stripping insulation from, crimping, and shrinking/insulating the electric lines.
The procedure for stripping insulation from, crimping, and shrinking/insulating the electric lines must be complied with and observed. The procedures are described in detail in the Repair kit for Cayenne harnesses NR.155-2.
Crimping samples are to be prepared before beginning work.
Information
Allocation of lines - see wiring diagram.
9. Crimp lines at -a-.
Connecting and routing wire harness for brake booster
9.1. Cut off lines in different lengths (due to the shrink-fit connections).
9.2. Slide shrink-fit hoses onto the lines.
9.3. Strip 10 mm of insulation off the wires.
9.4. Crimp the lines with crimping sleeves and the hand crimping pliers from the Cayenne repair kit for harnesses NR.155-2.
9.5. Slide the shrink-fit hoses over the crimp connections and carefully shrink them using the hot-air blower with special nozzle (recommended accessories for the repair kit for harnesses) so that it is watertight.
9.6. Wrap commercially available PVC tape all around the area of the connection points.
10. Secure the repaired area -b- to the main wire harness with tie-wraps.
11. Put the cover on the cable duct.
Putting the cover on the cable duct
Reworking
Subsequent work
1. Install the wiper motor.-> 921519 Removing and installing wiper motor - section on "Installing" 921519 Removing and installing wiper motor
2. Install left and rear covers in engine compartment. -> 700219 Removing and installing front cover (engine compartment) - section on "Installing" 700219 Removing and installing front trim (engine compartment)
3. Install heating/air-conditioning unit. -> 851519 Removing and installing heater/air-conditioning unit - section on "Installing" 851519 Removing and Installing Heater/Air-Conditioning Unit
4. Install the bracket for the dashboard. -> 701219 Removing and installing dashboard bracket - section on "Installing" 701219 Removing and installing bracket for dashboard
5. Carry out work instructions after disconnecting the battery. -> 2706IN Working instructions after disconnecting the battery Procedures