I just did this. With these headlights. let me see if I can find the paper I scribbled my wire color notes on..
I remember reading a lot about this because I also incorporated LED corner markers with the turn signals. It's a floating ground system where the signal powers up each side of the stock incandescent bulb to make the blinker flash, but that won't work with the LEDs or something like that. Either way, my notes show the order on both sides is Ground - Parking - Signal. So ground is ground, the middle wire goes to the DRL (even though this makes the "DRL" only work when the parking lights are on) and the end wire is the signal. That's how I wired mine up, though I ended up making harnesses to connect the factory connector, factory turn signal, LED headlight and LED marker light. Cleaner that way.
Double checking my Inspired Engineering install instructions, they do say to wire the DRL to the center wire in the harness which puts the DRL on with the running lights. If you're looking for a real DRL, connect that wire to any switched power source. The white LEDs light up when the headlights are on anyway.
Just a note, I've had these headlights installed for a few months and I'm very happy with them
Last edited by icrashbikes; 03-10-2017 at 06:58 AM.