Using LED lights on trailer

[Flipper Dog]

Hi all,
I have been looking through other treats but can not find any information on this.
I have a Facelift (T2) Touareg with tow hitch (or tow bar in my part of the world) which has been towing a trailer with standard incandescent light bulbs, no problems with this.
Now I have another trailer I need to tow that is fitted with LED lights, problem now is that the vehicle’s electrical system will not allow this. What I am experiencing is a persistent weak erratic flicking on indicator lights (amber ones), opposite signaling once the indicators are turned on, no reaction once driving lights are applied and the brake lights possessed with a mind of their own in reference to when it is time to function.

I have tried applying an additional ground wire from the vehicle’s ground to the trailer, and placing extra incandescent bulbs on the circuit to deceive the vehicle into the belief a load is present, but to no avail.

Spoke to a trailer specialist today in relation to his and they suggested you can purchase an adaptor which is fitted between the vehicle’s out plug and the trailer’s in plug, is this possible ?

I have approached Volkswagen on this issue and had the trailer wiring inspected which, surprise surprise, emerged as faultless. Advice was “don’t use LED lights!” and “We will post this as an issue to head office!” Translation…we don’t know what to do so stick our heads into the sand!

The complete removal and replacing the LED lights on trailer number 2 is not a problem if I have to but most modern trailers getting around now have LEDs on them so I will encounter this subject again.

Has someone a fix for this problem yet?

[sumar]

Hi Flipper Dog,
Yes I had to fix mine as I am getting my new Kimberly Karavan, hopefully late in the Week or early next. It has LED lights and I was aware of the problem. The fix was done in Brookvale NSW by Walkers Auto Electrics 02 99050073 cost including installation about A$ 850.00, talk to Bruce,

[Vegas Matt]

There is a simple adapter sold by U-Haul in the US that takes care of the LED trailer problem. It has been discussed on here and VWVortex. I don't know the part #'s, but they are on here. I think it may have been about $30USD

Matt

[Treg2]

Hi Flipperdog,

Just so happens that I am install LED's on my Jayco caravan at the moment.

Have not tested the lights with the Treg yet but expect that I will have the same issue.

The company that supply me with my LED replacement globes also supply load resisters that clamp inline to creates a resistance equivilant to a 21w filament bolb.

This is the link to their web sight LED TRAILER LIGHTS, LED MARKERS, LED CLEARANCE LAMPS, LED LIGHTS

I still have to install the side clearance LED's but once I have completed that I will connect up and see what happens.

Treg2

[4xMotionTDI]

Here's the Uhaul adapter.
U-Haul moving supplies: LED Light Trailer Module

[Flipper Dog]

Thanks all so far on your advice, this what makes this forum worth being a member of.

In Australia we have the following trailer connection standard according to Volkswagen .

On the vehicle side.

and


The trailer end.

We run 7 (small round, large round and flat) or 12 pin connections but I only need to use the 7 pin large round so the U-Haul is not looking very helpful.

Treg2's link is helpful however I was thinking more for something between the vehicle and trailer much like the U-Haul idea as I will most likely tow someone elses trailer with LED lights and will not have time to re-wire the circuit.


For everyones info this is a 7 pin flat.

[Mike's Panzer]

Valley makes the plug connector with balast bult in. 39008 is round 7 to flat 5. 53032 is round 7 to to 6 round.

[Devoman]

This what you need to do.And if you are wondering about this.This was givin to me from a friend who is a vw tech and got it from the rep.It works.This has been posted a very long time ago.

[Flipper Dog]

Thank you Devoman,
that is the simple DIY fix I am looking for.
Will try it out this weekend to see if it works.
Beats me why VW can not come up with this fix down this end of the world.

[Devoman]

Just make sure they are the right ones.Let me check before you do anything ok.I need to double check these are the right ones.I think the ones in the picture were in the testing fase at the time.I will get back here shortly.I have never done this to my Newer Airstream but still plan on doing it.
Here is the post I put up a long time ago to fix this.This will help out for those who have the LED problem.Remember though...This is only for one fix.The other could never be figured out but it does help alot.
LED Trailer & Brake warning fix for Touaregs. - Airstream Forums

This is the e-mail I got from them.If you notice though this has been a fix since around 2005 .Remember to get the right resistors and dont get any other.


Daniel,

I hope that this helps. Remember that these resistors need to be metal oxide and from what engineering was telling VWoA these should be 3 watt. I know that we have used 1 watt type from Radio Shack and they work sufficiently in the past.

Please keep in mind that you have to identify what wires are what on your harness. They may vary depending on the manufacturer of the harness adaptor. I would assume that any LED light needs to be modified for correct operation. As I mentioned to you I would modify the adaptor "pig tail" harness so that the trailer would work properly on another vehicle and also that if you use another trailer with regular lights on this Touareg that it will also work properly.

If you need any more information about this fix, send me a e-mail and I will send you some more photos etc.

Here is the pic for how it is done.
Remember the resistor are 100 ohm 3 watt.