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Topic: 4 round pin to 4 flat pin trailer wiring adapter? (Read 40 times) previous topic - next topic
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4 round pin to 4 flat pin trailer wiring adapter?
Yahoo Message Number: 136393
Hello I have '11 LD.  I appears to have four  pin round outlet for trailer lights.
 I will be towing a 500 lb utility trailer with no brakes.  It has a four pin flat plug.
 Is there an adapter anyone has had success with (no need for rewiring adapter)?  If not any suggestions..
Re: 4 round pin to 4 flat pin trailer wiring adapter?
Reply #1 –
Yahoo Message Number: 136394
You could try U-Haul.  They have a lot of that kind of stuff.

I wouldn't depend upon any standard for an adapter.  You may still have to rewire the LD outlet to match that particular trailer.

Dick
Re: 4 round pin to 4 flat pin trailer wiring adapter?
Reply #2 –
Yahoo Message Number: 136395
Good to know.  Was wondering about the standard (if any).
Re: 4 round pin to 4 flat pin trailer wiring adapter?
Reply #4 –
Yahoo Message Number: 136398
Check Walmart. 6 round to 4 flat is pretty common. The 2 you don't need are just dead connections.

John A Wozniak  Sent from iPhone Please excuse any typos
Re: 4 round pin to 4 flat pin trailer wiring adapter?
Reply #6 –
Yahoo Message Number: 136400
I think if I needed to adapt from the 4 pin round to 4 pin flat, for my own equipment, I would make my own adapter.  Get the two pieces, one flat and one round, verify the circuits so you know what wire does what for both the round and flat connectors, then solder the wires together, making an adapter perhaps 6" to 8" long.  Use some heat shrink tubing on the splices, then wrap the whole thing with rescue tape or with vinyl electrical tape, and you are done.  If you get a pre-fab adapter and there is anything non-standard with the wiring either on the RV or the trailer, you will have a problem.  Making a short adapter lets you be sure it is right, is inexpensive, and is easy to do.
 Many years ago, I maintained and towed canoe trailers as a leader in a white water canoe program.  Everybody's hitch connections were different.  Sometimes green was left and yellow right, and other times it would reverse.  Our solution was to have a 4 screw terminal block on the hitch end of the trailers, and to have an assortment of connectors with screw terminal connector ends on the wires.  We had a little 12v bulb on a socket with alligator clips that we used to test the connector.  We would plug the connector in to the person's car who would be towing, ground the test light, and identify each lead, then screw that lead to our terminal block, which we had marked.  It gave us a quick, easy way to deal with people with 4 pin flat, 4 pin round, 6 pin and 7 pin connections.

Ken F in NM
'08 MB
Re: 4 round pin to 4 flat pin trailer wiring adapter?
Reply #7 –
Yahoo Message Number: 136404
Thanks for the suggestions.  I'll be sorting it out over the next couple weeks.  Lets just say this 5x8 trailer purchase has a few rough edges.  I'm planning on carrying ATV or Yamaha 400 scooter on trailer.

1.  Safety chains too short on trailer.  Also  LD safety chain hook point restricts type of hooks or clips.

2.  Tongue jack installed had too much hang in the minimum position, promptly dragging and destroying it.  I found one on etrailer w/ 5 inches fully retracted vs. 9 inches as installed.

I can make it work, but if I were doing it over, I'd consider a trailer with a little higher ride height, not requiring so much drop in the drawbar.  I'd also not expect the utility trailer dealer was any kind of capable of getting them out the door in usable condition (at least for being towed behind a motorhome).
Re: 4 round pin to 4 flat pin trailer wiring adapter?
Reply #8 –
Yahoo Message Number: 136405
Well you ought to get by with a standard adapter for the wiring....
 As for the tongue jack I prefer the swing back on the lighter trailers like yours. They have a spring loaded pin that lets you swing them back up parallel to the trailer tongue.

One similar to this one.....
 http://www.wmjmarine.com/38571.html?gclid=CNW48Ya2gbUCFQSg4Aod0QIAPQ

Garry
Re: 4 round pin to 4 flat pin trailer wiring adapter?
Reply #9 –
Yahoo Message Number: 136406
I was looking at the swivel adapters and my go that route.  I've had them on other trailers in the past.  This particular trailer has a L channel frame and the swivel mounts tend to either be welded on or use U bolts.  I "think" the new A frame adapter will retract higher than a 6" stand welded onto the trailer, and therefor be protected.  But if it continues to be problematic, I'll have a swivel mount jack welded on.
Re: 4 round pin to 4 flat pin trailer wiring adapter?
Reply #11 –
Yahoo Message Number: 136411
Steve and others,
 Mechanical compatibility is one thing and electrical is another.  Just in case, I could check with one of those multimeters that have been discussed to make sure that right signal comes out on the right pin on the flat connector.  Looking for a blown fuse in the rig may not be much fun.
 On the other hand, I could be overly cautious and there is a rigorous standard all manufacturers adhere to.

Alex Rutchka, SE #4 '05 MB
Re: 4 round pin to 4 flat pin trailer wiring adapter?
Reply #12 –
Yahoo Message Number: 136412
For what it's worth, most Walmarts have a trailer-towing section back in with Automotive, and in that section's rack of electrical gear you can almost always find four-pin flat "diagnostic connectors."
 Each pin on the connector has a labeled LED associated with it, so you can quickly run through the brake and turn signal sequences and see which indicators light up. That has to be a faster way to test towing setups than going pin by pin with a multimeter.

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: 4 round pin to 4 flat pin trailer wiring adapter?
Reply #13 –
Yahoo Message Number: 136414
Excellent suggestion, I ordered one.  Beats the heck out of the way I would have gone about it before.