Procedure for Completing Towbar Wiring for Amarok for AUS Delivery

Install J432 trailer Detection ControllerFor those wanting to do their tow bar wiring I have just successfully done the following. Fitted the trailer detection control unit J432 part number 1K0 907 383F behind the dash drivers side on the left side of the steering wheel - just plugs in. I think the F donates the part version and I think you need the F version to get the programming option for Australia as the country. Anyway this part did program for Australia and I do not get any issues with fog lights

You also need to put 5 Amp fuses in 60 and 61 fuse positions – diagram below.

The unit needs to be programmed for your country. If you have the Ross Tech device run the module discovery (once fuses are installed) and go into the trailer module and set the correct country in the module hex code. Outside Europe you select “Reset of the world” except Australia – select Australia.

Make up Wiring loom from VW plug at rear of vehicle to trailer plugThen I made my own wiring loom to connect the VW trailer loom at the rear of the tub to a 7 pin flat trailer plug.

Fortunately the VW wiring loom has the mail plug already plugged in as a blank to stop dirt getting in the female end. Use this plug. The male end is the part of the electrical plug that is clipped to the vehicle so unplug the wiring harness from it and then remove it. Push out the rubber blanks in the back of so you can push in your harness wires with the male spade pins crimped on.

Male spade connectors (original ones) are available from http://www.automotive-connectors.com (about 30 cents each - vw charges $12.00). You need these as the male plug is a blank - you can even order the rubber seals for around the wires.

The connection mapping from the VW plug to the AUS 7 pin trailer plug is as follows. This shows mapping from the pin number of VW harness plug to the AUS trailer 7 pin plug.

Left Indicator VW pin 4 to trailer pin 1Right Indicator VW pin 3 to Trailer pin 4Earth VW pin 10 to trailer pin 3Tail Lights VW pin 11 and 12 - connect to trailer pin 7, VW put 2 3amp diodes in this circuit (one each wire before they are joined together) to stop voltage feedback to the trailer detection controller.Brake Light VW pin 7 to Trailer pin 6Reverse Light VW pin 1 to Tailer pin 2VW pin 8 permanent 12 volts ignition off with power.VW pin 9 another earthI have not worked out what two other wires do. 

Testing.

You either need to special VW testing unit to plug into the trailer socket (simulates the resistance load of the trailer) or a plug a trailer in. No voltage is sent down the loom without the unit detecting electrical load. Except of cause the 1.5 volts test voltage signals.

With the tailer plugged into the vehicle and the vehicle in 4WD you should not be able to turn On the “Off Road Function”. Lights on the trailer should work – if they are not working make sure your trailer wiring is good (I had this issue which slowed me down an lot on the install – earth on the trailer on one side was not good).

You can buy a replica version of the Hayman Reese tow bar at http://www. towbar saustralia.com.au  for just over $400 dollars. You will get a lot of wire that you can throw away but the physical bar is great. Use the wire to make your wiring loom.

Images

Short wiring loom showing covered with the shinny black insulation tape. Connector plug is the loom connection point to the vw trailer loom

Different angle for the rear trailer wiring loom that needs to be made up. Other wires you see are for electronic trailer brake controller (orange) and rear view camera (green wire and other black loom). I have not yet connected the permanent power and earth wires to a plug.

Picture from the rear of the vehicle

Picture showing the male side of the connect plug to the VW trailer loom with the female plug removed. Note male side of plug attaches to the vehicle. This needs to be taken off to make up the loom.

Picture showing the Trailer detection control unit installed behind the dash on the driver’s side – I just used double sided tape – there are comments that this should be installed behind the lower dash cover but the vw loom was not long enough . (ie unit would end up on the other side the bracket that it is stuck to) .