TheSamba.com :: View topic - Trailer wiring with out the converter box?

Tue Dec 28, 2010 10:13 pm

I have a plug adapter for my trailer lights that is mounted just above the bumper. Unfortunately it's no longer is hooked up to the vans wiring. If my research leads me correctly, I need a converter box to get the european tail lights to work with the single bulb trailer lights. Is this correct?

Is there no way of getting around the need for this box? I need to leave for Portland in about 5-6 days and need working lights and can't order the box from GoWesty since they are closed until Jan 3rd.

Since I will be traveling at night, I will obviously need taillights and of course brake lights. I'm less concerned with the turn signals, but obviously they would be good to have.

Any tips will be greatly appreciated.

Tue Dec 28, 2010 10:15 pm

You need a Euro to US converter box.

There's no way around it.

Tue Dec 28, 2010 10:25 pm

You can use any generic converter box from Walmart or something. It looks like that's all that GoWesty sells, with their instructions. I fit mine inside the wiring breakout box in the engine compartment, this is where I spliced into the van's wiring as well.

I don't recommend it but you can temporarily hook the van's brake lamp circuit to the left & right trailer lights to get the brake lamps working; no blinkers. The parking light can be directly connected to the trailer wiring. For all that work might as well put the converter box in.

Tue Dec 28, 2010 11:56 pm

The first european trailer wiring harness I bought was expensive, from a trailer place.
The second one I bought was the same exact part from Wlamart and it was around
$15. Really pretty easy to hook up. I removed the drivers side tail lamp and then
exposed the wires up the harness sheath towards the front od the van.
With your bentley see what wire is what and tap into it with your trailer harness.
They usually give you plenty of length so it shouldn't be an issue to reach up there.
Once you have all the wires in place either wrap them with tape or something else.
Then zip tie them in place away from the exhaust components, this is why I
have bought two of these units. The first was touching the muffler and melted the wiring.
Also it went back to the black box of the harness and melted that too, so I just
couldn't replace the melted wires.

On the bottom of this vent are small holes that you can not see in the picture but
you can zip tie the wires to them to keep the away from heat. The set of wires in
the middle are the trailer wires, the ones on either side are my additional backup lights
on my GW trailer hitch.
Good luck and hope this helps......................Tim

Wed Dec 29, 2010 6:50 am

You can do a simple converter with a $3 pack of diodes from Radio Shack. That is what I used to do when putting a towing harness on Vanagons in the days before the modern converter was available.

http://www.radioshack.com/product/index.jsp?productId=2062591

I used 4 diodes. They get wired together in a ' W ' configuration.

This will allow the brighter element in each tail light to be both turn signal and brake light. The turn signals won't blink while the brake lights are on though. That is the big advantage of the modern converter box.

Mark

Rhinoculips wrote: I have a plug adapter for my trailer lights that is mounted just above the bumper. Unfortunately it's no longer is hooked up to the vans wiring. If my research leads me correctly, I need a converter box to get the european tail lights to work with the single bulb trailer lights. Is this correct?

Is there no way of getting around the need for this box? I need to leave for Portland in about 5-6 days and need working lights and can't order the box from GoWesty since they are closed until Jan 3rd.

Since I will be traveling at night, I will obviously need taillights and of course brake lights. I'm less concerned with the turn signals, but obviously they would be good to have.

Any tips will be greatly appreciated.

Wed Dec 29, 2010 7:29 am

crazyvwvanman wrote: You can do a simple converter with a $3 pack of diodes from Radio Shack. That is what I used to do when putting a towing harness on Vanagons in the days before the modern converter was available.

http://www.radioshack.com/product/index.jsp?productId=2062591

I used 4 diodes. They get wired together in a ' W ' configuration.

This will allow the brighter element in each tail light to be both turn signal and brake light. The turn signals won't blink while the brake lights are on though. That is the big advantage of the modern converter box.

Mark

Can you explain this in more detail? If the diodes are in a "W" then there would be three wires going in and two going out. Is this correct? If so, which wires go to the outer part of the "W" and what goes the the middle? Then how is the bottom 2 'exit' points wired?

Wed Dec 29, 2010 7:34 am

The top center is from the brake light wire. The top left and right come from the left and right turn signal wires. The 2 bottoms go to the left and right trailer tail lights, bright filament.

Mark

Rhinoculips wrote:
Can you explain this in more detail? If the diodes are in a "W" then there would be three wires going in and two going out. Is this correct? If so, which wires go to the outer part of the "W" and what goes the the middle? Then how is the bottom 2 'exit' points wired?

Wed Dec 29, 2010 7:38 am

crazyvwvanman wrote: The top center is from the brake light wire. The top left and right come from the left and right turn signal wires. The 2 bottoms go to the left and right trailer tail lights, bright filament.

Mark

Rhinoculips wrote:
Can you explain this in more detail? If the diodes are in a "W" then there would be three wires going in and two going out. Is this correct? If so, which wires go to the outer part of the "W" and what goes the the middle? Then how is the bottom 2 'exit' points wired?

That makes sense. Thanks! Is there any 'neat' way of putting it all together or is is get taping things up?

Wed Dec 29, 2010 8:01 am

I just solder the diodes together, solder on the 5 wires, tape it all up.

The 4 diodes all point with the band end toward the trailer lights, bottom of the W.

If they don't have the 6A in stock you can use these 3A, assuming only 1 bulb per side of the trailer.

http://www.radioshack.com/product/index.jsp?productId=2062577

Mark

Rhinoculips wrote:

That makes sense. Thanks! Is there any 'neat' way of putting it all together or is is get taping things up?

Wed Dec 29, 2010 12:47 pm

If you don't want to make one up you can buy a converter box from NAPA for about $15.00. I did this about 2 months ago, very easy to hook up...

Wed Dec 29, 2010 1:57 pm

A modern converter is the way to go, since it allows the trailer turn signal to flash even when the brake lights are on.

I have not used a NAPA one but I assume it is typical. NAPA# BK 7551086

http://www.napaonline.com/Search/Detail.aspx?R=BK_7551086_0282455800

Mark

shepherdsond wrote: If you don't want to make one up you can buy a converter box from NAPA for about $15.00. I did this about 2 months ago, very easy to hook up...

Wed Dec 29, 2010 2:09 pm

I agree that you should probably just spring for a converter box unless it's really not available. The diodes would be inexpensive, but you won't have many places you can buy them whereas the converter will be available at most FLAPS, trailer supply stores, or places like Walmart (probably Lowes as well). It's easy to hook up the converter and not have to worry about things shorting out, and the converter will likely have a fresh flat four connector with it.

Another option is rig Euro-style lights on the trailer and use a round 5 or 6 pin connector. I used to do that with my sailboats because I like the visibility of the amber turn lights and separate turn & brake. No converter is involved, but you need to buy the lights, connectors, run extra wires on the trailer... so you're not ahead costwise or hassle-wise. Then if you have multiple cars and multiple trailers you need to do it all over again. I finally removed the amber turn lights and went back to standard flat-four connectors. I used an off-the-shelf converter box on the Vanagon (it was already there, but the wiring sucked so I tore it all out and wired it fresh.

Paul