Problems  Problems   Problems lol

 Okay, so my RV and Truck, like all vehicles used to be, are 3 wire 1157 dual bulb lighting systems (Left Turn & Stop,,,,,,Right Turn & Stop,,,,,Tail Lights). Similar I have three trailers all of which (like most trailers) are 3 wire so no problem so far.

 HOWEVER my car/toad I haul or tow to Florida is a 4 wire (Left Turn,,,,,,,Right Turn,,,,,,,Stop Light,,,,,,,,,Tail Light). Sometimes I tow that car and sometimes I use it to tow my golf cart trailer.  Its no big deal to buy a readily available cheap 4 to 3 Converter which I have installed on the car so I can tow my trailer which has the 3 wire systems and all works well as its already installed.

 BUT THE PROBLEM is when I tow the car as a toad behind the  3 wire RV and it (car) has the 4 wire lights!!!!!!!!!!!!!!

 So I go to Flea Bay and they have a 3 to 4 (some call them 2 to 3) converter which will supposedly allow my 3 wire RV to tow the 4 wire car yet all will work yayyyyyyyyyyyyyyy I hope???

 QUESTION I just wonder if having BOTH those Converters (4 to 3 to tow trailer behind car, then another 3 to 4 so RV can tow car)  will cause a wiring or cross talk or feedback rendering one or both inoperable?? I hope not since they are mostly just diodes inside those small plastic boxes. Sure, there are other ways to skin this cat (light bar on car trunk etc etc), but it would be neat and easy (once all is wired) if the 4 wire car will work behind the 3 wire RV and also,, if a 3 wire trailer will work behind the 4 wire car (but that's easy and already in and working)

 Anyone used that 3 to 4 converter before?? Thoughts???

 I figure there's no way to find out except to try it, so later next week I will let yall know what happens, cross your fingers.

 John T

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Comment by david craft on November 30, 2014 at 4:39pm
Great John, I figured you got it solved by now. I just wanted to explain what has worked for me. These threads get indexed by the search engines as well so it may help folks in the future. I like how in the 2-2 setup, power from the motorhome doesnt run through any diodes to get to the lights. Considering a 40 foot run of wire to the back, a voltage drop over a diode would be good to avoid. Not faulting your install. I used to be a 2-3 guy for a few years. Im sure what you have is working fine. I just picked up a hanging thread and put in my 2 cents..
Comment by R. Randall Halton on November 30, 2014 at 10:32am

That's en-lighting to know that the wiring and converters are functioning John.

Comment by John "T" Nordhoff on November 30, 2014 at 9:31am

 Yep I am past that conflict, all works fine now. To summarize, I bought BOTH a 3 to 4 (RV to toads) and 4 to 3 (4 wire toads can pull a small 3 wire trailer) Converter and all systems and combinations are good n bright and all works well yayyyyyyyy:

 The toads (car and truck) are 4 wire (Left Turn, Right Turn, Brakes, Tail)

 The RV is 3 wire (Left Turn & Stop, Right Turn & Stop, Tail)

 I need the RV to tow the 4 wire toads (4x4 Pickup or car) and all its lights work and the 3 to 4 converter I bought on E bay works fine.

 I also needed the toads (4 x 4 pickup) to be able to tow a 3 wire trailer and the 4 to 3 Converter I bought on E Bay works fine.

 I think what helps keeps it all working fine and all the lights shining nice and bright is how I wired good grounds all the way to the Neg post on the batteries (RV and Toads) and theres absolutely no cross talk or interference  IM A HAPPY CAMPER 

 Fun chat, thanks yall

 John T

Comment by david craft on November 30, 2014 at 2:24am
I usually use the same 2 to 2 to do the rear clearance lights as well. That way I get more intensity. Even though they brighten up with the engine running, the clearance lights are still not stock brightness without the diodes. Removing the front lights from the circuit does the trick.
Comment by david craft on November 30, 2014 at 2:08am
I know your probably past this dilemma John, but, I used to always use the 2 to 2. I like this because its less invasive. You cut the wires to the stop light onthe toad, and install the 2 to 2 there. Then your stop/turn wires hook after the unit and you brake light onthe toad does the stop and turn function. Perfectly legal. Your toad still uses all the original lighting during standard use. The 3 to 2 for the toad to tow wires in with no conflict.
Comment by John "T" Nordhoff on June 20, 2014 at 7:37am

  Yo Wolf Man, Its seems nowadays the 7 pole RV type plug and receptacle has become the standard if you look at new trucks off the assembly line, UNLIKE the older 6 pin what I call horse trailer plugs. STILL those are set up for 3 wire trailer systems, they have the Left Turn & Stop,,,,,,,Right Turn & Stop,,,,,,,,and Tail Light terminals. If the truck is a 4 way they have the 4 to 3 converters built in as trailers are still 3 wire systems. UNFORTUNATELY I need to do the OPPOSITE LOL I need to convert the 3 wire RV to tow the 4 wire car and all its lights still work right which it appears the 3 to 4 converter on Flea Bay is supposed to do, wont know until next week when I try it....

 John T

Comment by Lakota Wolf on June 19, 2014 at 4:05pm

Thats a good question to ponder John,,,,, I plug everything into my 7 prong RV plug,, excluding magnetic lights that I use on a rare occasion. I used to have a 3 way, a 4 way and even an old 5 way plug hanging off the truck,, BUT with salt air, they don't last very long corroding beyond recognition.



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