I was just out taking out all my old nasty rear end wiring, and when I started putting everything back together when I put the left blinkers on, the right ones blinked as well. I had cut out the resistor! The problem was, that when the blinker and brake wires met and the blinkers were applied, the current was jumping to the other side via the brake wire.
Long story short, make sure you put a resister back in if one was there, or you will just be scratching your head in confusion (I would know...)
