trailer wiring

Trying to wire up a 6 pole round trailer socket to my rear tail lights, everything is working but the brake lights on the trailer. It is a 97 Grand Am 4 cyl., wanted to tow a single place motorcycle trailer. Any suggetions what to wire to for the brakes? By the way, my first post here.

If anyone is interested, after searching the web I found that I need the 5 wire to 4 wire converter(have not checked the auto stores yet for one). Then I am going to install small LED trailer taillights, hoping not to draw to much power from the system.