Welcome 2008,You should have five wires there. One left turn and brake( one wire ), one right turn and brake ( one wire ), one running lights, one reverse, one dedicated ground. Do you know which one is the ground? If you do know and you are absolutely positively sure you have the ground, you can attach it to the negative post of a 12 VDC battery, touch your other wires to the positive post and see what lights up. Mark them with their function with a piece of tape. Then follow this wiring diagram, standard 7 post round connector. If I could figure out how to post pics I would do that for you. Cant figure it out so have to give you this link. http://www.etrailer.com/faq-wiring.aspx . All this being said, if you dont know absolutely positively which is your ground, do not do this. You could damage your wiring, start a fire, etc. One thing that would be helpful is knowing where you are located. Maybe some one is close that could lend a hand.
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