Engine Wiring Harness
Engine Wiring Harness
Special tools, testers and auxiliary items required
• Hose Clamp up to 25 mm Diameter (3094)
• Torque Wrench (V.A.G 1331)
• Drip Tray (VAS 6208)
• Hose Clip Pliers (VAS6362)
Conditions
• The ignition is switched off.
• The engine must be cold.
Procedure
- Check the DTC memory for all control modules before removal using the Vehicle diagnosis, testing and information system (VAS5051B) in"Vehicle OBD" mode.
- Remove the engine cover.
- Remove the battery. Refer to => [ Battery ] Battery.
When disconnecting and connecting the Battery, the procedure must be followed as described in the repair information. Refer to => [ Battery, Disconnecting and Connecting ] Battery, Disconnecting and Connecting.
- Remove the battery tray - arrows -.
- Remove the windshield wiper arms and plenum chamber cover. Refer to => [ Windshield Wiper System ] Windshield Wiper System.
- Remove the plenum chamber bulkhead.
The following illustration shows the wiring harness as viewed from the windshield with the hood open.
1. Plenum chamber bulkhead
2. Wiring harness
3. Front window
- Remove the wiring harness - 2 - from the mounts - arrows -.
- Remove the screw - 1 - and nut - 2 - from the plenum chamber bulkhead - 3 -.
- Remove the plenum chamber bulkhead - 3 - upward from the vehicle.
- Remove the engine control module (J623).
- Remove the connector - arrow B - on the engine control module - arrow A -.
- Release the wiring harness guide - A - at the retaining tab - arrow -.
- Pull the wiring harness guide - A - upward.
- Remove the wiring harness from the bracket - arrow A -.
- Unclip the wiring guide near the transmission mount - arrows B through D -.
- Disconnect the cable tie on the black 14-pin connector at coupling 1 in the left of the engine compartment - arrow B - and remove the connector from the bracket.
- Disconnect the black 14-pin connector at coupling 1 in the left of the engine compartment - arrow A -.
- Unclip the cable guide - arrow C -.
- Remove the connector (10-pin, close to the left headlamp - arrow A -) from the bracket - arrow B - and then disconnect it.
- Release the wiring harness connecting base at the starter - arrow B -.
- Release the wiring harness connecting base on the bracket for the oil filter bracket - arrow A -.
Component location => [ (Item 3) Connecting Base ] Intake Side.
- Pull the wiring harness carefully off the brackets.
- Release the wiring harness clip and remove it from the bracket on the oil filter bracket - arrow -.
- Disconnect the connector from the EGR vacuum regulator solenoid valve (N18) - 1 - and throttle valve control module (J338) - 2 -.
Throttle valve control module (J338) installation location => [ (Item 2) , 50-pin Connector ] Intake Side.
- Loosen the clip near the oil filter bracket - arrow -.
- Disconnect the connector from the camshaft position sensor (G40) - arrow -.
Component location => [ (Item 7) 3-pin Connector ] Intake Side.
- Disconnect the connector from the fuel temperature sensor (G81) - 1 - and fuel metering valve (N290) on the fuel high pressure pump - 2 -.
Fuel metering valve installation location => [ (Item 7) 2-Pin Connector ] Top View.
- Pay attention to the wiring guide.
- Remove the wiring harness.
- Disconnect the connector from the oil pressure switch (F1) - arrow A -.
Component location => [ (Item 4) ,
1-pin ] Intake Side.
• It is necessary to remove and install the oil filter bracket in order to disconnect the connector from the engine speed sensor (G28).
- Oil Filter Bracket.
- Disconnect the connector from the engine speed sensor - arrow -.
- Disconnect the connector from the intake flap motor (V157) - arrow A -.
Intake flap motor installation location => [ (Item 1) ,
5-pin Connector ] Intake Side.
- Remove the wiring harness from the bracket - arrow B -.
- Disconnect the connector from the fuel pressure sensor (G247) - arrow A -.
- Remove the wiring from the bracket - arrow B -.
- Remove the nut from the fuel line - arrow D -.
- Remove the cable guide from the fuel rail (high pressure reservoir) - arrow C -.
- Disconnect the connector from the fuel pressure regulator valve - arrow A -.
Component location => [ (Item 5) 2-Pin Connector ] Top View.
- Disconnect the connector from all fuel injectors - A -.
Injection unit installation locations => [ (Item 1) Injection Unit Connectors, 2-Pin ] Top View.
- Open the spring clamp - arrow B - using (VAS 6362) and remove the line on the fuel rail (high pressure reservoir).
- Remove the line - arrow C -.
- Clean the return line connection on the fuel injectors before removing.
- Dry the return line connections.
- Disconnect the connectors from all glow plugs.
Follow the removal and installation procedure exactly. Refer to=> [ Glow Plug Connectors,
Removal and Installation ] Top View.
Glow plug connector installation locations => [ (Item 8) Glow Plug Connectors ] Top View.
- Remove the wiring harness and wiring guide from the fuel rail and guide the wiring harness out.
- Disconnect the connector - arrow - from the engine coolant temperature sensor (G62).
Component location => [ (Item 7) , 2-pin ] Exhaust Side.
- Guide the wire out - arrows -.
The illustration shows the coolant temperature sensor wiring harness - arrow -.
- Arrow C - shows the wiring harness to the following components:
• Exhaust pressure sensor 2 (G451)
• Charge pressure actuator position sensor (G581)
• EGR valve 2 (N213)
• EGR temperature sensor (G98)
- Remove the wiring harness from the bracket - arrow B -.
- Arrow D - Wiring harness from the bracket on the cylinder head cover.
- Arrow A - Wiring harness to the EGR temperature sensor (G98).
- Arrow B - Wiring harness to the EGR valve 2 (N213).
- Arrow C - Bracket for the EGR valve 2 (N213) wire.
- Remove the heat shield - arrows - and disconnect the connector from exhaust pressure sensor 2 (G451) - 1 -.
Installation location => [ (Item 2) 3-Pin Connector ] Exhaust Side.
- Install the heat shield - arrow -.
Installation location => [ (Item 3) 3-Pin Connector ] Top View
- Disconnect the connector from the charge pressure actuator position sensor (G581) - arrow - on the turbocharger vacuum diaphragm and guide the wire out of the mounts.
- Disconnect the connector from the EGR temperature sensor (G98) - arrow A - and guide the wire out.
EGR temperature sensor (G98) connector installed position => [ (Item 1) Connector ] Exhaust Side.
- Remove the noise insulation.
• Assembly Overview, the vehicle from underneath
• Check the wiring routing and the heat shield location.
Installation position EGR valve 2 (N213) => [ (Item 4) Connector ] Exhaust Side.
- Remove the heat shield - arrow B - and slide the heat shield off the connector.
- Disconnect the connector from valve 2 for EGR (N213).
- Cut the cable tie - arrow A -.
• Engine compartment assembly overview:
- Remove the intake hose.
• Check the wiring routing before guiding the wire out.
- Carefully guide the wire - 1 - out between the turbocharger intake scoop - 2 - and the pre-heating hose - 3 - - arrow A -.
- Remove the entire engine wiring harness carefully from the engine compartment.
Installation
Installation is performed in the reverse order of removal. Note the following:
Follow the procedure removal and installation exactly. Refer to=> [ Glow Plug Connectors,
Removal and Installation ] Top View.
Make sure all of the connectors are seated securely.
Return the heat insulation to the original locations. Refer to=> [ Heat Shield Installation
Information ] Engine Wiring Harness Installation Information.
Replace all self-locking nuts, seals, gaskets and clamps.
Secure hose connections with spring clamp.
Install spring clamps with (VAS 6362) or (VAS 6340).
Follow the instructions. Refer to => [ Engine Wiring Harness Installation Information ] Engine Wiring Harness Installation Information.