Help with wiring a trailer wiring harness

I need to install a 4 prong wiring harness for a trailer hookup. Is it a splice situation or is the a plug somewhere I can find to plug into.

Cheers
~James

Splice, and you will need a control module to convert the car's separate turn and brake signals into the trailer's combined turn and brake functions. The module will have instructions about how to do it.

I just plugged the wires straight into the back of the light and took the opposite indicator from the other side. It has pin outs in the back of the rear lights for the proper VW towbar wiring

I've got the Bosal wiring harness. I was thinking the 4 pin might be easier to install. Are there Bosal to 4 pin converters. It looks bigger than other connectors I saw at the store.

GoFaster said:

Splice, and you will need a control module to convert the car's separate turn and brake signals into the trailer's combined turn and brake functions. The module will have instructions about how to do it.

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^^ this.

Assuming you're wanting to tow a standard North American trailer, you need to convert the seperate-brake lights-and-turnsignals your Jetta uses to the combined-brake-lights-and-turnsignals your trailer uses.

Someone may sell a Bosal to 4-pin with an integral signal converter...but the point is that it's more than just pin swapping that's required.

The standard converter looks like this:

http://www.amazon.com/Reese-Towpower-74209-Trailer-Converter/dp/B0008G1NNY

and has the 4-pin wiring already attached. You can access the required input signals at the Jetta's rear signal light housing....I vaguely recall both left and right turn signals are present at both lights.

Seatman, our trailer wiring is a bit different to that in the US.

What kind of connector do I need to plug into the lights?

This is why I plugged mine into the light fitting

http://forums.tdiclub.com/showthread.php?t=37966&page=5

we don't have combined turn and stop lights, tho.

DPM said:

we don't have combined turn and stop lights, tho.

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Thats why you need the harness converter he listed or one like it..

You need one with a separate supplied 12v to the converter module..

I've got the converter. I was just hoping to avoid splicing into the wires and would prefer to use a plug in system.

Can't you just take the extra wire from the other side and run it across? That's what my car has. The proper kit from VW just plugs into the rear lights too.
The only other thing I did was fit a standard buzzer for the indicators so I knew if they stopped working.

DPM said:

we don't have combined turn and stop lights, tho.

Click to expand...

I don't get what you mean, How could anyone have combined turn lights? Ours go to each side and not all to the one side then across but as I just put in the previous post we just run the wires from the opposite side of the car across then have them all going to the towbar from the one side if you know what I mean.

The car, like most European-made cars, has separate bulbs for the stop light (red lens) and turn signal (yellow lens).

The trailer, on the other hand, in North American, uses the same bulb (and one red lens) for *both* the stop light and the turn signal... hence the need for a wiring converter....for the fourth time in this same thread.

Alright no need to be sarky It makes sense now so you may go in peace

Just explaining it as clearly as possible... should search lead someone here some day... since there still seemed to be some confusion.

Got the wiring done this evening.

Thanks for all the help.
~Cheers

Not to bring up an old thread or anything...but getting ready to do the wiring on mine. Understand everything fine but all I need to know is...do I need a powered or not powered converter? Thanks

aidan_mkiv said:

Not to bring up an old thread or anything...but getting ready to do the wiring on mine. Understand everything fine but all I need to know is...do I need a powered or not powered converter? Thanks

Click to expand...

I don't know what you mean by powered or non-powered converter. I did mine this weekend and the converter cost $27 from OReilly's auto parts. They sell them at etrailer.com so i think they are pretty much a common kit.

Included in the kit is the following
1) converter
2) 18" 4 wire extension cable
3) 4 splice connectors
4) screw for ground wire
5) dielectric grease
6) plug for cable
7) LED test cable

I used the Bentley, but if I recall correctly here are the colored wires to know at least from the kit I used (Jetta wire color/Converter wire color - function):

RED/red - brake
GREY-BLACK/Yellow - left turn
GREEN-BLACK/Green - right turn

I can't recall the tail lights color on the Jetta, but the converter wire was Brown. White is the ground wire on the converter.

To run the wires to the hitch I drilled a 7/16 hole and added a grommet. I cut the wires on the extension cable closer to the end near the convertor and spliced after running the wires back through the grommet. I used two zip ties on each side of the grommet to help keep the wires from pulling through and siliconed on both sides.

This is the exact kit that I bought.

http://www.amazon.com/Hopkins-46155-Taillight-Converter-Universal/dp/B0002Q8036

Has anyone ever used this custom harness from etrailers? It looks to be a plug-and-play affair. I am ordering it and will report back with my findings.
http://www.etrailer.com/p-118667.html