What would cause a bow light to over heat?

I have a Lowe aluminum SeaNymph 175 fishing boat, equipped with a pole mounted, bi-color, bow light with built in courtesy light (to illuminate the front casting deck). The light over heats and trips the circuit breaker after several minutes. The rocker switch is a three position type: Up = Navigation (bow and stern lights on), middle = Off, Down = Anchor (white stern light only). I can leave it in the Anchor position and it does not trip the circuit breaker. What should I look for? I opened up the light and the connections all seem intact. The following link is for the manufacturer's mounting instructions, but the light was installed already when I bought the boat brand new at a local marina. I ume the light base and wiring were factory installed. a href="http://www.perko.com/instruct.php" rel="nofollow"http://www.perko.com/instruct.php/a