what is the extra wire for? And is this the reason my signals will blink normally for a few seconds then blink fast?

Help

and how do I fix this?

 

So this takes me to my next question about the rear signals and the 4 wires that are located on them. both sets of lights that the harley shop ordered for me are only 2 wire hmmmmmm????

 

something makes no sense, front should match front and so on, some after market ones require a load stabilizer to work properly. think badlands makes them

 

i took my stock signals apart. when i hook the black and blue up to battery, the light is bright. when i hook up the purple and black or purple and blue...the light comes on but not as bright. does this make any sense??

 

The 3 wires are probably ground/running/turn.

 

Front turn signals have two functions.....running light and turn signal. To do this they have a dual filament bulb. So you have a blue wire running to the dim filament for the running light, a violet wire running to the bright filament for the turn signal and the 3rd wire is black which is ground.

Your lights are blinking fast because the turn signals you have on do not match the resistance (too low) and thus the amp draw from the turn signal module that your stock bike had. So it blinks fast which is an aid to tell the rider a bulb is burned out.

Stock harley rear turn signals are turn signals only....so it is a single filament bulb and has two wires running to them, black for ground and probably violet again for the turn signals.

I suggest if you are going to be working on your bike to purchase the factory service manual. It will have the wiring schematics in it which will describe the following:

black = ground
blue = running light
violet = turn signal