971355 Replacing Wire Harness For Brake Booster
WM 971355 Replacing wire harness for brake booster
Tools
Technical values
Preliminary work
1. Disconnect battery. => 2706IN Work instructions after disconnecting the battery
2. Remove the carrier for the instrument panel. => 701219 Removing and installing carrier for instrument panel - section on "Removing"
3. Remove heater/air-conditioning unit. => 851519 Removing and installing heater/air-conditioning unit - section on "Removing"
4. Remove linings in engine compartment. => 700219 Removing and installing front cover (engine compartment) - section on "Removing"
5. Remove wiper motor. => 921519 Removing and installing wiper motor - section on "Removing"
Removing wire harness for brake booster
Installation position of wire harness for brake booster
1. Remove cover on cable duct (above the pedals) -arrow-.
Removing cover on 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- (top right, next to the pedals).
Cut off and expose wire harness for brake booster
3. Remove fabric tape and tie-wraps in area -b- and expose the remaining lines.
4. Screw off ground strap -1- on the centre firewall.
Removing ground strap on the centre firewall
4.1. Screw off the fastening nut on the centre firewall and remove the ground strap with the twist lock -arrow A-.
4.2. Unclip wire harness at the retaining clip -arrow B-.
5. Pull off connector on brake fluid reservoir -4-.
Pulling off connector on brake fluid reservoir
5.1. Release connector on brake fluid reservoir -arrow A- and pull it off -arrow B-.
6. Pull off connector on brake booster -5-.
Pulling off connector on brake booster
6.1. Release connector on brake booster using a suitable aid (e.g. angled piece of wire) -a- ( -arrow A- ) and pull it off -arrow B-.
7. Pull off way-sensor connector (brake assist) -6-.
Pulling off way-sensor connector (brake assist)
7.1. Release way-sensor connector (brake assist) using a suitable aid (e.g. angled piece of wire) -a- ( -arrow A- ) and pull it off -arrow B-.
8. Pull off pressure sensor connector (brake assist) -7-.
Pulling off pressure sensor connector (brake assist)
8.1. Release pressure sensor connector (brake assist) using a suitable aid (e.g. angled piece of wire) -a- ( -arrow A- ) and pull it off -arrow B-.
9. Loosen wire harness on the centre firewall.
9.1. Open retaining clips -arrows A- and remove the line -arrow B-.
9.2. Open both holders (brake assist) -arrows C- and remove wire harness -arrow D-.
Removing wire harness on the centre firewall
10. Remove rubber sleeve -8- on the centre firewall.
Removing rubber sleeve on the centre firewall
10.1. Unclip wire harness for brake booster from the centre firewall at the retaining clip -arrow A-.
10.2. Remove rubber sleeve on the centre firewall in direction of the engine compartment -arrow B- and remove wire harness for brake booster.
Installing 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 the engine compartment towards the interior -arrow A- and fit rubber sleeve on the centre firewall.
1.2. Clip in wire harness for brake booster on the centre firewall with the retaining clip -arrow B-.
Fitting rubber sleeve
2. Secure wire harness on the centre firewall.
2.1. Insert wire harness into the two holders -arrows A- and close the holders -arrows B-.
2.2. Insert line into the two retaining clips -arrows C- and close the retaining clips -arrows D-.
Securing wire harness on the centre firewall
3. Plug in pressure sensor connector (brake assist) -7-.
Plugging in pressure sensor connector (brake assist)
3.1. Plug in connector on pressure sensor (brake assist) -arrow- until it engages securely.
4. Plug in connector on way-sensor (brake assist) -6-.
Plugging in connector on way-sensor (brake assist)
4.1. Plug in connector on way-sensor (brake assist) -arrow- until it engages securely.
5. Plug in connector on brake booster -5-.
Plugging in connector on brake booster
5.1. Plug in connector on brake booster -arrow- until it engages securely.
6. Plug in connector on brake fluid reservoir -4-.
Plugging in connector on brake fluid reservoir
6.1. Plug in connector on brake fluid reservoir -arrow- until it engages securely.
7. Screw on ground strap -1- on centre firewall.
Securing ground strap on centre firewall
7.1. Clip in wire harness on the firewall with the retaining clip -arrow A-.
7.2. Connect ground strap together with the twist lock to the threaded bolt on the centre firewall -arrow B- and secure 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.
8. Crimp the lines in area -a- (in cable duct above the pedals).
Connecting and routing wire harness for brake booster
8.1. Cut off lines in different lengths (due to the shrink-fit connections).
8.2. Slide shrink-fit hoses onto the lines.
8.3. Strip 10 mm of insulation off the lines.
8.4. Crimp the lines using crimping sleeves and the manual crimping pliers from the repair kit for Cayenne wire harnesses NR.155-2.
8.5. 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 wire harnesses) so that they are watertight.
8.6. Wrap commercially available PVC tape all around the area of the connection points.
9. Secure the repaired area -b- to the main wire harness with tie-wraps.
10. Fit cover on cable duct (above the pedals) -arrow-.
Fitting cover on cable duct
Subsequent work
1. Install wiper motor. => 921519 Removing and installing wiper motor - section on "Installing"
2. Install linings in engine compartment. => 700219 Removing and installing front cover (engine compartment) - section on "Installing"
3. Install heater/air-conditioning unit. => 851519 Removing and installing heater/air-conditioning unit - section on "Installing"
4. Install the carrier for the instrument panel. => 701219 Removing and installing carrier for instrument panel - section on "Installing"
5. Carry out work instructions after disconnecting the battery. => 2706IN Work instructions after disconnecting the battery