I put a cargo box on the back of my 2010 but it now blocks my license plate so I mounted it on the back but I need to light it. I bought two leds to get it done but I dont know which wires to splice into. Ive got access to the rear taillights but which wire is which? Some pics attached.
why don't you just hook into your original license plate lights? there's even enough of a gap to get the wires out to your new lights/
try this TL-LHD.pdf or even better/simpler, check it with a multi-meter (buy something at harbourfreight & get a basic one for free....)
