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Tue Apr 26, 2016 6:10 am

I would like to splice in a trailer style harness for when I am flat towing my baja I can hook the brake/turn lights up as if they were trailer lights. My baja already uses the trailer converter to use trailer style rear lights, but wasnt sure if I could just splice it in up front or if I need some sort of one way diode to protect the circuit?
Has anyone done anything similar, am I just overthinking this?

Tue Apr 26, 2016 6:17 am

If you already have a "flat 4 trailer" wiring plug - just go to the fuse block and direct wire your towed vehicle system to your new trailer wiring harness.

Tue Apr 26, 2016 6:26 am

This is what I did so I did not light up or energize any circuits in buggy other than lamps on rear... This would protect trailer converter if you have one...

Also I put a plug/socket connector in front of buggy so tow umbilical disconnects from buggy when removing tow bar... My umbilical stays zip tied to my tow bar....

But if you have "trunk" you could just coil up umbilical and toss in trunk when not towing...

Dale

Tue Apr 26, 2016 7:15 am

thanks. that was pretty much what i was thinking. no trunk, and there looks to have been a similar connector to that previously on the car (though its seen better days).

Tue Apr 26, 2016 3:38 pm

Pollak is a good brand, typically sold in NAPA stores everywhere. the cheap chrome ones are not compatible with each other, you may buy a mating connector somewhere that does not fit.be wise, buy Pollak

Tue Apr 26, 2016 4:37 pm

And the diodes? I'll probably order them, no good supply stores around here.

Tue Apr 26, 2016 6:43 pm

ponyboy88 wrote: And the diodes? I'll probably order them, no good supply stores around here.

I typically use a 6 amp, 50 PIV diode from "Radio Shack" BUT they are going through some bad financials and don't know if there is still a store in your area, so many have closed.... Many online places like Digikey will have them...

Something like this will work...

http://www.digikey.com/product-detail/en/micro-commercial-co/6A05-TP/6A05-TPMSCT-ND/773696

Dale

Fri Apr 29, 2016 1:11 am

This post is probably just noise to the OP after Dale provided an answer to his issue. But for others, my info may help their situation.

I rigged both my '65 Baja and my '58 Baja with a 4-connector cable plug in the nose, a cable that stayed with the tow bar, and just connected the plug in the nose to the wire harness near the fuse block. For years, the tow vehicle was my '61 F100 which has 1 2-filament bulb on each side.

In the Bajas with stock 61-67 tail lights, the tail/stop lights served well for both stop and turn function. I don't remember how I managed to prevent feedback, but maybe it was because I connected the wires from the front plug to the turn indicator wires to the back of the Bug. With all red taillight lenses, the turn indicator bulb on top lights up red anyway.

I took out the tow harness years ago when I added cage structure out to the beam and the tow bar wouldn't fit anymore. I have a trailer if I want to tow a Baja anyway. That fixes the issue pretty well right there. :wink:

A friend of mine bought one of the Harbor Freight tow light setups with magnetic lights and uses it to tow with the tow bar or to tow on his trailer.

For another suggestion of how to deal with this issue...

Back in the early 70s, when I bought my '65 Bug, it was sitting near the Mexican Border with a dead engine and I was north of LA, some 150 miles apart.

So I borrowed a pickup truck and bought a pair of trailer tail lights with license plate brackets, a 4-prong trailer connector, and 4 25' spools of 14 gauge wire. I wired it all up, tested it and taped the harness every foot.

When I got there, I hooked up the tow bar, plugged the harness into the back of the pickup and ran the wires over the Bug to the back using things like the radio antenna to hang the wire bundle. I used the existing license plate bolts to attach the license plate brackets of the tow lights to each side of the license plate on the car and away I went. The only tools I needed were a screw driver and a 7/16" wrench for the 1/4-20 hardware on the license plate. The license plate lenses on the bottom of the trailer lights lit the VW plate better than the pickup's plate was lit.

Fri Apr 29, 2016 6:37 am

I also have a "light bar".... Its a set of $25 lamp holders and cables with plug ... Its like a trailer lighting "kit" from O'Rilleys... The two lamp housing are mounted on four foot length of shelf bracket angle iron (the type with multiple holes) and I can plug it in to any 4 wire connector and drape it along towed vehicle and either use bungee cord or zip ties to secure to rear of towed vehicle (specially to somebodies trailer with crap wiring) .... Something similar to what tow trucks use... Since it was original made for mount on back of fiberglass buggy hence the bar as buggy body is not steel there for not magnetic....

Horror Fright makes a tow set with magnetic bases also...

http://www.harborfreight.com/12-volt-magnetic-towing-light-kit-63100.html

Also since all my tow vehicles have 7 pin connectors I carry a 4 pin to 7 pin adapter in each vehicle... In case I have to rescue somebodies trailer or what ever...

Also it help to use "standard" plug/pin configurations so it fits most any vehicle...

Wiring standards can be found at places like e-trailer...

http://www.etrailer.com/faq-wiring.aspx

Dale

Sat Apr 30, 2016 8:12 am

I put two dedicated taillights in the back of my buggy with a separate 4 wire going back in their own harness.
It solves the issue of feedback and the American Verse European taillight issue.
I have the same plug as Dale bolted to the front bumper with a harness jumper that can be either left with the towbar or pulled off.

I also have a two wire plug by each rear light so I can remove the tow lights if necessary. I have only taken them off once when installing my Full flow Oil filter when they conflicted. I fixed that issue and they are back on.

Mon May 02, 2016 2:21 pm

Timely subject for me. Bought a flat 4 wire trailer harness and hooked it straight to my tail lights for a trip to the frame welder. Lights worked very erratically. Is this the diode issue? It might be that these are LED lights?

Mon May 02, 2016 3:04 pm

IF you are just using as trailer lights and not connecting to buggy/rail harness, no it is not a diode issue...

Did tow vehicle have factory harness with flat four connector for trailer lights? OR did you just add "something in"...

Usually erratic lighting problem is loose connection or ground problem...

Tow lighting is no different then standard vehicle lighting, quality of parts and workmanship (connections) count...

Fact that they are LEDs might be issue, BUT SHOULD NOT if package is presented as universal lighting kit...

Dale

Mon May 02, 2016 3:53 pm

Make sure you have clean grounds.

Tue May 03, 2016 10:00 am

Yes, factory flat four connector and I wasn't running it through the rail harness (as I've stripped just about everything off the frame for powder coating).
Probably was a ground issue. I kinda just threw it on for a pretty short trip.
Thanks

Tue May 03, 2016 12:58 pm

This thread confuses me because years ago, I spliced a flat four plug straight into my cars harness under the hood and used it many times without issues.

Tue May 03, 2016 3:38 pm

sloboatnova wrote: This thread confuses me because years ago, I spliced a flat four plug straight into my cars harness under the hood and used it many times without issues.

You can do that with no problems.... The isolation diodes just keep front turn signal bulbs on front fender of vehicle being towed from flashing in your rear view mirrors...

Dale

Tue May 03, 2016 6:53 pm

Dale -

I think the diodes purpose is to prevent cross-function in cars that use the same bulb and filament for brake and turn lights. If the circuits are not kept separate, as I did in my Bajas as I described above, when the turn indicators lights up the left side lights, it will light up both sides, and vice-versa. So both tail lights would light up on both the towed vehicle and the towing vehicle whenever either turn indicator is switched on in the tow vehicle.

If the same bulb and filament are used for brake and turn indicator, there must be diodes to prevent that crossfeed.

As for the front turn indicators on the towed vehicle operating when it is towed, I LIKE that. For one thing, it lets me know that the lights are working. For another, it increases the visibility of the turn signal to drivers on the side. You might have noticed that some late model cars have turn indicator lamps on the side of the front fender near the door.

Tue May 03, 2016 7:30 pm

dustymojave wrote: Dale -

I think the diodes purpose is to prevent cross-function in cars that use the same bulb and filament for brake and turn lights. If the circuits are not kept separate, as I did in my Bajas as I described above, when the turn indicators lights up the left side lights, it will light up both sides, and vice-versa. So both tail lights would light up on both the towed vehicle and the towing vehicle whenever either turn indicator is switched on in the tow vehicle.

If the same bulb and filament are used for brake and turn indicator, there must be diodes to prevent that crossfeed.

As for the front turn indicators on the towed vehicle operating when it is towed, I LIKE that. For one thing, it lets me know that the lights are working. For another, it increases the visibility of the turn signal to drivers on the side. You might have noticed that some late model cars have turn indicator lamps on the side of the front fender near the door.

My main purpose for adding diodes was to prevent feeds back into buggys system as to possibility of turning on dash lights or front parking lights or turnsignsls...In other words "fuctionally same as pure trailer lights".. Never had any thoughts of cross ups and false illumination of any bulbs... Basically with isolation diodes, any buggy wiring or circuits are nonexistant as far as towing are concerned...

Bacially any tow vehicle with a 4 wire connector (or popular 7 pin RV style connector) "should" have proper tail, stop, and turn signal wiring and functionally to proper illuminate'"trailer" lighting bulbs or LEDS...

http://images.lmgtfy.com/?q=trailer+light+wiring

Keyword here is "trailer lighting"...

Dale

Wed May 04, 2016 6:14 am

I also used a flat connector at where my rear cage attaches to my buggy.
I also used boat trailer lights mounted on my cage (incase the water gets deep).
Norm
Makes for easy cage removal and an extension cord will hook it to my truck.
After running it like this awhile, I need to add some heat shielding or change something (exhaust or move the wiring).
I'm probably going to change it all.

Wed May 04, 2016 7:34 am

A little dielectric grease in connector will also prevent corrosion in connector...

Dale