I have a 2017 Dyna Lowrider S. Replacing a rear turn signal and license plate light. I unplugged everything under the seat to get to the wires I need. Everything has something to plug into, that I can see, accept this one plug. Does anyone know what it is? It's on the left side, coming from up front, and it's female.

 

any wire colors???
hard to say but looking at an older schematic, could it be for the anti-theft tracking module which you probably do not have.

 

Black, red, and white colors. I searched for a solid 30 minutes. It doesn't seem like anything plugs into it. Just wanted reassurance. You could be right. I was guessing maybe for diagnostics?

 

I had some time so I did some searching for you.

If I can read wiring diagrams correctly there seem to be only two three-wire plugs under the seat on your bike:

the optional security siren would have
Red wire with orange stripe
White wire with green stripe
Black wire
Uses a delphi 3-place GT 150 connector


The JSS (Jiffy Stand Sensor) would have
Red wire with white stripe
Light green wire with gray stripe
Black wire
Uses a Molex MX 150 connector

You might want to check the colors of those wires again.
.

 

Many Thanks! Just checked it is a red wire with an orange stripe, white wire with a green stripe, and a black wire. So looks like it's the optional security siren.

Thanks to you, I can put it back together and rest at ease.