2006 Outback 23 KRSI am replacing the 7 Pin Pigtail, it was worn out and unreliable. Interesting thing, when I was disconnecting the old one the yellow wire was clipped off and unused. I did not connect the yellow one on the new pigtail and the left blinker/brake still works! Every schematic I have seen show the yellow as left blinker... On the trailer end there is only a yellow/white wire, no pure yellow, and that goes to the upper marker lights.Usually I am trying to figure out why things don't work that should, now I am trying to figure out why this is working when it shouldn't be!What am I missing?

Don't count on the wiring colors to match on either side of the connection. Go by which pin # does what.

downtheroad wrote:L turn and stop light.Got that, read post, yellow wire not connected to anything but L signal works???

Look closely as it could be faded or weak orange which is normally connected to the center pin. This center pin is an auxiliary connection for items like back up lights.

There are 2 primary standards. The SAE standard is used on cargo trailers and is what most of us know. There is an RV standard that some of the RV manufacturers use that sounds like what you are observing. One reference for this is: http://www.hopkinstowingsolutions.com/doc/trailer-wiring-codes.pdfI personally wire all my trailers to the SAE standard as being the most universally used and recognized.

7 Pin Wiring - Yellow Wire??? | Good Sam Community

Miles_Away
Explorer
Dec 10, 2017
If it was on the truck side, clipped off and not used and everything else worked, it might be for a back-up light. Most truck plugs are wired for them, but most trailer don't have back-up lights.
LanceRKeys
Explorer
Dec 05, 2017
Just went through this with my truck. I ended up going wire by wire with a test light to see what each one did and wired it accordingly. Mine may or may not be to the standard, but it works correctly.

Oh, on another note, wear safety glasses when drilling for a mounting location for the plug. A simple job turned into an emergency room visit to get metal pulled out of my eye.
mkirsch
Nomad II
Nov 21, 2017
I must've purchased an RV plug for a utility application, or vice versa, at some point because I followed the colors molded into the plug when wiring it, but they were wrong.
JBarca
Nomad II
Nov 20, 2017
Yes, as DougE stated there are different wiring color standards depending on who puts them on.

See here from Etrialer some nice pic's showing this

They sell both configurations just you need to realize there is a difference and pick the right one when buying.

The good news, the auto makers at least have the pins all in the right place so if the colors change, it does not affect the trailer working.
Throttlemonkey
Explorer
Nov 19, 2017
Great info, I had never seen that before, much appreciated!

The yellow wire is likely for backup lights which is perfect, I just bought some LED floods to mount on the side of the trailer for backing up my driveway at night, now I know where to connect them!
DougE
Explorer
Nov 19, 2017
There are 2 primary standards. The SAE standard is used on cargo trailers and is what most of us know. There is an RV standard that some of the RV manufacturers use that sounds like what you are observing. One reference for this is: http://www.hopkinstowingsolutions.com/doc/trailer-wiring-codes.pdf
I personally wire all my trailers to the SAE standard as being the most universally used and recognized.
enblethen
Nomad
Nov 19, 2017
Look closely as it could be faded or weak orange which is normally connected to the center pin. This center pin is an auxiliary connection for items like back up lights.
Throttlemonkey
Explorer
Nov 19, 2017
downtheroad wrote:
L turn and stop light.

Got that, read post, yellow wire not connected to anything but L signal works???
sch911
Explorer
Nov 19, 2017
Don't count on the wiring colors to match on either side of the connection. Go by which pin # does what.
downtheroad
Explorer
Nov 19, 2017
L turn and stop light.

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7 Pin Wiring - Yellow Wire???

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