A-4 trailer lights

As anyone used these connectors to make a "splice-free" trailer light harness ?

I would like to hear of your experiance.

I've been using this setup for about six years.
Works great with a powered Valley converter. I just plug the converter into the trunk power outlet when I use it and drape about a foot of flat four wire out under the trunk lid. Then store both wires in the tray behind the spare tire when "unhooked" from my trailer.

Looks interesting. I was going to use .110" female spade connectors.

Looks like I can order them from 1stVWParts:

wires are $5.80 each x 3 = $17.40
Housing (BR) is $11.25 each x 1 = $11.25
Housing (31-BL-S) is $5.15 each x 2 = $10.30

Total: $38.95 + shipping

Oops, don't you need 4 wires: Taillight (BL), Brakelight (BR), Left Turnsignal (S), and Right Turnsignal (S)

So the new total would be $44.75 + shipping

I just ordered the parts.

I just wired up my Wagon yesterday (bulb housing is a bit different on the wagon but basically the same). I was going to go this route and purchase the VW connectors/wires and make it plug and play. I always like to do things the right way, clean install. But then I was thinking, why do I need it to be plug and play? And why am I going to spend $50+ dollars for connectors and wiring that once plugged in will most likely not be disconnected again?

I chose to order a pack of 10 .110" spade connectors from McMaster-Carr for $8.84. I purchased the Reese trailer light adapter from Amazon for $24. Both parts took 2 days to arrive at my door, no wasted time driving around.

No added wires needed as the length of wires from the Reese trailer adapter were plenty long enough. Just crimp the spade connectors on the end and plug into the back of the tail light housing. Technically it is plug and play. Easy to remove and use on a friends car if so needed. I left the adapter and trailer plug wiring end in my driver side storage compartment in the back of the wagon. When needed I will just pull it out. You can do the same thing in the sedans.

Just my two cents.

loco, I was going to use the .110" connectors (btw, you could have got them cheaper at your FLAPS), but just ordered the VW connectors for a "cleaner" fit. How did you connect the power lead to the power port on the driver's side of the wagon? I was thinking of just using a "cigar" plug-in connector so that the power isn't continuously going to the trailer converter. I plan on storing the cable in the same place as you.

I ordered this converter from Amazon - Reese Towpower 74209

http://www.amazon.com/Reese-Towpowe...3024125&sr=8-11&keywords=reese+trailer+wiring

There was no power lead necessary. My trailer is a 5 x 8 with small lights so I judged this would be okay.

I understood that use of an un-powered converter may cause problems due to the way VW does their circuits. Just about every thread I've read on hooking up lights, both here on TDIClub and on other VW sites, say a powered converter is the way to go.

I'm looking at either a

Hopkins 46365 Short Proof Power Converter


or a

Curt 56146 SMD Trailer Wire Converter

I did a lot of research on this as well on both of the forums. I read mostly the same thing but also one thread that had the link to the Reese I used that swayed me that way. I don't forsee a problem if I just use a trailer with the basic two light setup. My trailer also has LED lights so almost no power is being used.

If I would have seen that Curt powered converter I would definitely have payed the extra $5 just for the security.

I will say that wiring the converter up was so simple. Just need a $3 test light from Harbor Freight. I pulled the steel protector plate across the back of the wagon which exposed the factory wiring loom to the passenger side light. Ran my wire in the factory loom for the right tail light.

I have a Nu-Way 5x8 trailer I bought back in the 90s. It has the required front & rear side marker lights (and a license plate light in the left taillight housing), so I have a total of 7 bulbs just as running lights. I think I'll need the power!

I just found a "cheaper" Curt powered adapter:

Curt 56187 3 to 2 Wire Power Converter



From the description at the Curt website, this one handles 7.5 watts/ circuit while the other model only handles 6 watts. I've asked Curt for more info.

Running LED trailer lamps eliminates any worry of circuit overload, as they just don't draw that much current. Plus, the LEDs are almost indestructible, as they can tolerate lots of abuse like empty trailers (or also in my case, an empty car dolly) will give them.

True, but don't you have to put resistors in the vehicle circuit if you replace incandescent bulbs with LEDs? Or will the converter isolate the trailer LEDs from the vehicle wiring?

I have a diode box, yes, but it isn't powered separately (meaning it feeds off the rear light harness as depicted in Herm's original post).

romad said:

I just found a "cheaper" Curt powered adapter:

Curt 56187 3 to 2 Wire Power Converter



From the description at the Curt website, this one handles 7.5 watts/ circuit while the other model only handles 6 watts. I've asked Curt for more info.

Click to expand...

It looks like the 56187 is NON-circuit protected while the Curt 56146 IS circuit protected.

Herm TDI said:

As anyone used these connectors to make a "splice-free" trailer light harness ?

I would like to hear of your experiences.

Click to expand...

See Custom Wiring Harness link in my signature.

romad said:

True, but don't you have to put resistors in the vehicle circuit if you replace incandescent bulbs with LEDs? Or will the converter isolate the trailer LEDs from the vehicle wiring?

Click to expand...

There's more than enough resistance from the incandescent lamps in the car so that the electro-mechanical flasher has enough current through it to operate correctly, even without a converter (five or six wire w/ separate turn lamps on the trailer).
If you switch the car AND the trailer to LEDs the current will be reduced enough that the flasher won't work properly.

The LED resistors? They're shunts (semi-short circuits) to increase the current draw back up to what the incandescents used to pull. You're not saving electricity / alternator load if you use these shunts.
Shunts AND incandescents will likely bump up the current enough to continually pop the fuse.

Herm, I hooked up my wiring using those connectors this weekend; I only used 2 of the repair wires.

I got my trailer lights working.
I used the "MME" light converter: http://www.ebay.com/itm/160879406932?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

I got one of these powered converters for $9.00 (free shipping)
I also used the wired ground in the "31-BL-S" Connector. With my installation all three of the terminals of this connector were used. This made a neat, clean harness that nearly looks OEM. Totaly a plug & play harness.
Another personal touch to my harness was the actual power plug. My power cord has an LED to indicate that the converter is powered on.
Everything works...emergency flashers, stop lights, turn signals, and running lights too.

Here is a link to my trailer: 6'x10' bed. The deck is marine grade plywood. Being aluminum it is really easy to manuver by hand,

Herm TDI said:

I got my trailer lights working.
I used the "MME" light converter: http://www.ebay.com/itm/160879406932?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

I got one of these powered converters for $9.00 (free shipping)
I also used the wired ground in the "31-BL-S" Connector. With my installation all three of the terminals of this connector were used. This made a neat, clean harness that nearly looks OEM. Totaly a plug & play harness.
Another personal touch to my harness was the actual power plug. My power cord has an LED to indicate that the converter is powered on.
Everything works...emergency flashers, stop lights, turn signals, and running lights too.

Click to expand...

For power connection, I was thinking of just using a plug for the power port in the back of my Jetta. Both +12 vdc and the ground would be through there. When I wasn't using the trailer, I'd just unplug the connector.

romad said:

For power connection, I was thinking of just using a plug for the power port in the back of my Jetta. Both +12 vdc and the ground would be through there. When I wasn't using the trailer, I'd just unplug the connector.

Click to expand...

I do plug into the rear utility power outlet.
The only reason that I did not route the ground through the utility power oulet was to minimise the wires in my harness. That is why I went with the "31" position of the connector.

My power supply plug was something I had tossed into my spares bin. I liked the idea of having an LED to give me a visual indication of power "on".

I plan on using 1/4" split-loom to corral the wires.

I decided to follow your lead and use the "31" position in the connector. Once I get the wiring routed and "loomed", I'll take a photo.

I just installed a Westfalia hitch on my 05 MK4 Sedan.

I couldn't bring myself to pay for the connectors to plug into the tail light bulb holders for a splice-free installation.

VW wants $18 alone just for the 1 pin connector! Part 191972701

I bought a MK3 Jetta trunk light harness for $22 shipped from eBay. It has 3 of the 3-pin connectors, 2 of the 1-pin connectors, and several 2-pin connectors that won't be needed (but I think they might be useful for a Passat owner). And it has the pins/wiring already so I didn't need to buy any of those repair kits that come with the yellow wire with the pin on the end.

Also, Volvo sells repair pins/wire for about a dollar each - they don't come double ended, so if you need 2 pins, order 2. This is instead of 000979133AB. All Volvo dealers should have a drawer full of them.


Hope this helps someone else save a few bucks!

romad said:

I decided to follow your lead and use the "31" position in the connector. Once I get the wiring routed and "loomed", I'll take a photo.

Click to expand...

Driver Side Wiring


Pax Side Wiring

I wanted to thank you guys (Herm & Romad) for the quick references in this thread, much appreciated! I installed my Westfalia hitch this weekend & wiring converter using the power outlet in the cargo area. Great quick reference for wiring it all up! Loaded up the shop's utility trailer with ~1000lbs & it hauled with no issue! Now to find me a folding motorcycle/utility trailer to haul!

Will the curt light kits work on the mkvi? I am hesitant on cutting into the factory wires.

This thread is for MK IV models; you'd get a better response if you posted your question in the MK VI forum.

However, IF the MK VI taillights have the same sockets built in to them, then you should be able to use any POWERED adapter kit with the connectors and repair wires to hook them up. No cutting of factory installed wiring. BTW, precisely WHICH Curt light kit model were you considering?

Check out this link for how-to on the trailer wiring.

http://www.tdiblog.com/tdi-do-it-yo...g-harness-for-mkiv-vw-golf-jetta-jetta-wagon/

cevans, if you are replying to TDI_Dan's post, he is asking about a Mark VI 2011 Golf.

BTW, that blog entry describes the same DIY that KCTDI and I did with our vehicles as mentioned earlier in this thread. Looks likes a lot of us are thinking alike. I used Herm's initial post of this thread as my part number reference for ordering the connectors and wires.

Try www.drawtite-hitches.com and search their T-Connectors. They show plug-in kit for Mk V and Mk VI Jettas. I have a question into them about 2010 on Golfs. I'll post when I hear.

Rich