Hi all - this isn't actually RV related, but it is trailer related. I purchased a flatbed from a co-worker over the weekend and I had to re-wire the 7 blade connector since it had been driven over (or something). I was able to get things working, but I wanted to run this by anyone who would know. I have the following wires;Yellow - Left TurnRed - Trailer BrakeBlack - Ground???Blue - ???Green - Right TurnBrown - Tail/running lightsThere are two things that are strange right out of the gate. First, no white/ground wire. I have black wired into ground right now, and while I dont think it would be anything else, I haven't yet verified that (ie, remove it, and see if everything fails). The other is that the trailer brake is on red...when everything says it should be on blue. The brakes indeed work, and it's recognized by the controller...but very strange. Right now, I have the blue wire not connected to anything, but I believe its the aux/charging circuit for the breakaway battery. Still need to verify that too. That said, is there any sort of "other standard" out there that would explain, or at least validate what I've found so far?

https://en.wikipedia.org/wiki/Trailer_connectors_in_North_America

How old is it? From having trailers for 20+ years and my own experience I would guess that it's been rewired at some point. How old is it?

Blue is supposed to be the backup light circuit.

Its a 1999, and anything is possible that it was re-wired. However, based on the discussion with the owner it was rarely used, so while certainly possible - it seems unlikely.

ScottG wrote:Blue is supposed to be the backup light circuit. Blue is brakes and trailers rarely have backup lights because they would serve little purpose. I'm sure OP could find a wiring diagram as easily as any of us, the question was is the setup he has of any standard.

Odd 7 pin wiring harness | Good Sam Community

Lynnmor
Explorer
Jun 12, 2018
dougrainer wrote:
NONE of the previous schematics and even the Internet Links are WRONG for RV's. Just goes to show the Internet is not always right.

Brown----- RT
RED--------LT
BLUE-------Electric Brakes
WHITE------Ground
BLACK------12 volt positive
GREEN------Running Lights
YELLOW-----Center pin unused but if used Reverse lights.

The link to eTrailer, that I posted, showed exactly that!
Farmboy666
Explorer
Jun 12, 2018
dougrainer wrote:
Farmboy666 wrote:
dougrainer wrote:
NONE of the previous schematics and even the Internet Links are WRONG for RV's. Just goes to show the Internet is not always right.

Brown----- RT
RED--------LT
BLUE-------Electric Brakes
WHITE------Ground
BLACK------12 volt positive
GREEN------Running Lights
YELLOW-----Center pin unused but if used Reverse lights.

Before you attempt to correct me-----I have wired and repaired miswiring on hundreds of 7 way RV trailers. Since this is an RV forum, the correct answer is posted above

Now, what confuses some people is 4 way BOAT or Utility trailer wiring
4 way flat is
YELLOW---LT
BROWN ---Running lights
WHITE----Ground
GREEN----RT

So, some know 4 way flat and then use the same colors when connecting to a 7 way plug. Which is wrong. Doug

Why don’t you read the original post, he doesn’t care what’s normal, he wants to know if anybody has seen a trailer wired like his.

If someone wired it wrong, then it is ridiculous to ask if someone has seen his wiring. I am telling him HOW to correctly wire HIS trailer so it will work on any vehicle that is correctly wired. Make it correct, not work around the problem. I was also responding to the mistaking wiring links so people will realize those links are wrong. Doug

Well he’s the one asking if anyone has seen his wiring so your calling his question ridiculous? He has already stated he can google a wiring diagram himself without any help. Don’t be so sensitive Doug, you’ve been wrong before.
dougrainer
Nomad
Jun 12, 2018
Farmboy666 wrote:
dougrainer wrote:
NONE of the previous schematics and even the Internet Links are WRONG for RV's. Just goes to show the Internet is not always right.

Brown----- RT
RED--------LT
BLUE-------Electric Brakes
WHITE------Ground
BLACK------12 volt positive
GREEN------Running Lights
YELLOW-----Center pin unused but if used Reverse lights.

Before you attempt to correct me-----I have wired and repaired miswiring on hundreds of 7 way RV trailers. Since this is an RV forum, the correct answer is posted above

Now, what confuses some people is 4 way BOAT or Utility trailer wiring
4 way flat is
YELLOW---LT
BROWN ---Running lights
WHITE----Ground
GREEN----RT

So, some know 4 way flat and then use the same colors when connecting to a 7 way plug. Which is wrong. Doug

Why don’t you read the original post, he doesn’t care what’s normal, he wants to know if anybody has seen a trailer wired like his.

If someone wired it wrong, then it is ridiculous to ask if someone has seen his wiring. I am telling him HOW to correctly wire HIS trailer so it will work on any vehicle that is correctly wired. Make it correct, not work around the problem. I was also responding to the mistaking wiring links so people will realize those links are wrong. Doug
bucky
Explorer II
Jun 12, 2018
A lot of equipment trailers don't use 7 wire connectors. Go to Tractor Supply and buy 2 things. A female 6 wire end and a converter to plug it into your 7 wire truck.
Open the package and read the wiring schematic to be sure, but I think that is the issue.
Farmboy666
Explorer
Jun 12, 2018
dougrainer wrote:
NONE of the previous schematics and even the Internet Links are WRONG for RV's. Just goes to show the Internet is not always right.

Brown----- RT
RED--------LT
BLUE-------Electric Brakes
WHITE------Ground
BLACK------12 volt positive
GREEN------Running Lights
YELLOW-----Center pin unused but if used Reverse lights.

Before you attempt to correct me-----I have wired and repaired miswiring on hundreds of 7 way RV trailers. Since this is an RV forum, the correct answer is posted above

Now, what confuses some people is 4 way BOAT or Utility trailer wiring
4 way flat is
YELLOW---LT
BROWN ---Running lights
WHITE----Ground
GREEN----RT

So, some know 4 way flat and then use the same colors when connecting to a 7 way plug. Which is wrong. Doug

Why don’t you read the original post, he doesn’t care what’s normal, he wants to know if anybody has seen a trailer wired like his.
MEXICOWANDERER
Explorer
Jun 11, 2018
He wants to know which color does what on HIS vehicle to Socket wiring harness(?)
dougrainer
Nomad
Jun 11, 2018
NONE of the previous schematics and even the Internet Links are WRONG for RV's. Just goes to show the Internet is not always right.

Brown----- RT
RED--------LT
BLUE-------Electric Brakes
WHITE------Ground
BLACK------12 volt positive
GREEN------Running Lights
YELLOW-----Center pin unused but if used Reverse lights.

Before you attempt to correct me-----I have wired and repaired miswiring on hundreds of 7 way RV trailers. Since this is an RV forum, the correct answer is posted above

Now, what confuses some people is 4 way BOAT or Utility trailer wiring
4 way flat is
YELLOW---LT
BROWN ---Running lights
WHITE----Ground
GREEN----RT

So, some know 4 way flat and then use the same colors when connecting to a 7 way plug. Which is wrong. Doug
MEXICOWANDERER
Explorer
Jun 11, 2018
2oldman
Explorer II
Jun 11, 2018
Derick wrote:
Yes, I can google, I know what they SHOULD be.....this is a thread on what they actually are.
Without being there and using a voltmeter, I wouldn't know.
MEXICOWANDERER
Explorer
Jun 11, 2018
You have a classic and still very much in vogue T.T.M.A. Truck Trailer Manufacturers Association.

Wire harness color code arrangement.

Big rig. 18-wheeler

Blue is also used for power to the inside the van trailer ceiling lights AUX

Black is clearance lights

Brown is tail lights

Red is for stop lights

And 12 o'clock high is the big white pin for chassis negative

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