"Can you help me fix the wiring on my old trailer?" #%@%^*$_!*#^$*# yeah

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greymouser7

greymouser7

Vagrant Vagabond “Veni Vidi Vici”
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78002 down the road from Atascosa, Texas
My 69 year old uncle is a 'sugar daddy' to a 31 year young lady. Never mind that!
He set her up with a business on her grandmother's property selling trailers. (She also works at a Toyota plant)

You know some times I think am smart or stupid and then I get a reality check working with others. There are some beacons of sunshine and dark pits of hella stupid...

I work my way past 'why this girl hasn't done any of this leg work' {hella...} and (as requested) dive head first to help a friend of the family, i guess...

7 wire set up,
two derelict pickups which NEITHER have working trailer plugs/outlets/connections working...
have to bring the 6 year old daughter with me while the wife works-of course she gets bored so I am also keeping an eye open watching to keep her safe,
this grandmother's single wide mobile home trailer is F I L T H Y (still has her 3month passed on grandmother's dentures in the bathroom,
I DO have good trailers to reference,
I had a single sheet copy diagram of wiring schematic for the connector ( I assumed was accurate, but Noooo),
girl got off of her shift at 06:00 AM, is tired and cranky (no biggie, i worked in a pipe full of asset holes right!) and I got done helping OTHER family at midnight last night,

i get me and the 6 year old ready, feed 2 cats, dog, feed/clean 2, two week old kittens and head out
dig for my multimeters, extension cords, surge protector, battery charger as a verified 12 volt source, wire strippers, test light, buy some supplies,
get there and trailer has a connector with 8 wires and 6 connectors
wires are not the color of the designation of the connector

I disconnect the two tail lights of the OLD RUSTY trailer, clean the contacts, check the bulbs, check the grounds and then commence checking continuity on the tail light wiring

Brown wire is the running lights
yellow is brake/blinker for one side, green the other side
white is a ground, blue is brakes,

there is black wire labeled battery for a break away system that engages brakes with a fist size battery tied into what i guess is a solenoid that engages the drum brakes when the trailer miraculously falls off the truck - i think it charges with the running lights

bad trailer has TWO green wires, one is a ground besides white-eventually figured that out and tied them together into the connector's harness

bad trailer has a different black wire and a second white wire

good trailer has 2 whites, 2 blacks, 1 brown, 1 yellow, no green

Neither trailer matches the diagram (which as a brainwashed MT, the documentation was always our HOLY reference point and NEVER questioned on the big bombed SLBM's)

good trailer is verified good after i convince the young lady to let me take the truck to the auto parts store and check/verify all the fuses -one fuse missing, one blown, truck now good-it took over an hour to convince her to do this -NOW I have a reliable power source to check a completed connector (all wired back up)

the male/trailer connector on the old, rusty trailer is warped, chewed up and I easily mix up top from bottom which are slotted for installing on the truck -so I wired the crappy trailer for the diagram, no bueno,..
wire up the crappy trailer connector like the good trailer, no bueno, reverse top to bottom reference with crappy connector
BINGO! We are now progressing...
grounds are ****, i am not quite seeing double in the heat but am second guessing my name and all perceptions...do i have enough grounds, do i have not enough grounds:

running lights check, but weak, weaker on the drivers side

blinkers check SAME but weak on drivers side

running lights on -some times the left (inside the taillight plastic assembly) running light blinks, sometimes the top, or bottom, or both of the TWO filaments of the tail light bulb blink

running lights off, left blinker works great

clean, clean, wire wheel fresh metal where grounds are, all over
it gets better, then it gets worse

introducing the running lights into the circuit re routes where the electricity is flowin through the bulb

connect the trailer onto the hitch on the pickup for more ground - right side is brighter,

left side is still hella dim

am gonna run extra wire tomorrow, but ALL IDEAS are GREATLY APPRECIATED! thank you!

despite seeming intelligent in this slew of writing, I am a noob, and am fumbling my way thru what some of you guys solve in minutes, lots of frustration
 
You don't mention which wiring you have so here is the chart for them all.

TRAILER WIRING.jpg
 
My uncle showed me a neat way to do the tail lights. Use a 16 ga extension cord. 3 wires 1left 1right and 1running lights. An make sure you have good grounds everywhere you need them. You can tie in the side lights at the end or at the side.
The ground thru the plug and brakes and the breakaway use heavier wire.
 
Glad u got it fixed. With wiring like that I just start from scratch with all new stuff. U can drive urself crazy trying to figure things out. Kim
 
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X2, I use them on occasion, but stuff them full of dielectic grease to slow down the green wires.
Borrowed my brother in laws car trailer, the only lights that worked on it were the brake lights.
I replaced every light on that old trailer, just because he is a good guy, and he said when I borrowed it, to bring it back whenever I wanted to.
I have a new car trailer but for a year and a half, I have a broken old rusted cuda sitting on it, just cannot find enough time to finish stripping it out.
I hate borrowing stuff, but I will not return anything broken, even if I did not do it.
 
I've been beating my brains out trying to figure out what's wrong with my trailer brakes on my car trailer. I did away with the factory installed Scotch locks first thing! I have a Tekonsha Prodigy brake controller in my truck...been there since the truck was new in 04. I have an intermittent code flashing on the controller....NC and sometimes OC. When those are flashing, the brakes on the trailer won't engage. When it has a C (connected) the brakes work fine. I've replaced both the plug on the truck, and the plug on the trailer, and it still does the same thing. I think my next move is to hook to the trailer and take it to the dealer I bought it from to get it checked. They have a gizmo that they can hook to the truck plug, and then hook it to the trailer plug to see which way the problem is. Any ideas? Grey Mousers frustrations kinda hit home....lol.
 
Oh By The Way,

In the end, I tested an idea on the ground.:

I ran a wire from the negative terminal of the battery (truck and trailer completely hooked up) to the negative on the passenger tail light. No changes to blinkers or brakes until I turned the running lights.
Blew a fuse on the truck with the running lights AND blinker/brakes.
Seems like there was a short on the power line.
 
i need to rewire my trailer, and put new lights on em
I cant remember the occasion, but I picked up some LED tail lights during a FABO fundraiser, I just need to find a way to mount em
 
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