Wire Colours For Tail Lights

[Sleb]

My question is there are 3 wires going to the 3157 tail light bulb. The colours are black, brown and blue/white. I need to know which one is the ground and which one is the brake/turn. The other should be tail/running light. I'm adding a load resistor to stop the quick flashing as I have installed leds.

Thanks for your help

 

[Sleb]

So I think:

Black = Ground
Brown = Tail/Running Light
Blue/White = Brake/Turn

Please correct me if I'm wrong