Hi guys

So I finally got around to installing my towbar electrics that I got from Towbars Direct (Towbars Direct | Witter Towbar Systems, Tow-Trust Towbars, Westfalia Automotive, Thule Towing Systems (Brink), Bosal, GDW, PCT Automotive, Westfalia Monoflex, Westfalia SIARR) in the UK. I ordered the "Single Electric Kit (12N) with Multiplex By-Pass Interface Relay" for just £26.45. They won't ship to Australia, so I had them ship to a mate who then forwarded it to me. Ended up costing me a total of about $50 for the unit and getting it sent to me - BARGAIN!



I was pretty worried about doing the wiring and getting the scotch locks on properly and onto the correct wires. Thankfully I had access to Elsawin so I could check up on which wires were the correct ones to tap. Removing the rear lights is very simple if you have a torx screwdriver set to remove the 2 screws holding each light in. There is a 4 pin plug that has 2 catches on it that you need to release the plug from the light units.

On the right hand side I tapped 3 of the wires. The plug has numbered pins to make things easier, as well as the colour coded wires. On the right hand side they are as follows:
Pin 1 - Black and Yellow - Tail light
Pin 2 - Black and Green - Right Indicator
Pin 3 - Black and Purple - Brake light
Pin 4 - Brown - Earth



On the left hand side I only tapped 1 wire - the indicator. On the left hand side the wiring is as follows:
Pin 1 - Brown - Earth
Pin 2 - Black and Red - Brake light
Pin 3 - Black and White - Left Indicator
Pin 4 - Black and Yellow - Tail light



Testing the above wiring my tail light (when lights are on), brake light (when brake pedal is depressed), and left and right indicators work perfectly. I don't have reverse lights or side lights on my little trailer so haven't bothered trying to wire them yet. I probably should at some stage, but I am happy for now. At the moment I am powering the unit off the 12V supply in the boot - again, I'll investigate alternative options at some stage but for now I am happy.

Hope those of you that are looking for an alternative find this useful. it's cheap and it works. Of course, it does not have the trailer stability program that the OEM wiring harness does, so the caveats that go with that apply if you go this route. I have a tiny little motorcycle trailer so don't feel I need it.