Taillight kit - are backup and brake lights supposed to work?

I got the "Deluxe cargo box" with my new TX which included the taillight kit. The lights have a top red section and a bottom white section, similar to the way taillights and backup lights look on autos and pickups. However, I notice that only the red taillights work when the lights are on. Should the white lights come on when I put it in reverse? Also, are there supposed to be brake lights? Nothing changes when I press the brake pedal. I'm not finding much info about how these lights are supposed to work.