Turn signal problems

I bought some after market front turn signals for my 98 sportster (turn signals were gone when I bought it) and the turn signals have 2 wires (red and black) and the bike has 3 wires (black, purple and blue). While trying to figure out which wire goes where I found that there is a constant 12 volts on the purple wire with the ignition on (figure this is for the running lights). When I check the voltage on the brown wire there is 0 volts until I turn on the turn signal and then there is a constant 12 volts, it does not oscillate between 0 volts and 12 volts. However if I turn on the hazards it does. Anybody know how to fix this? Thx

That did the trick. Thx.