Starboard Side Light Troubles??

I own a 2003 Triton TR186 with a Marine Master trailer with trailer brakes. I have encountered a problem that has stumped me so far. I am desperately seeking some help as I'm sure it would take far too long to have someone fix it for me. It's prime bass fishing time.

The trailer has three side markers on each side, plus of course a stop lamp. Yesterday, when I turned the running lights on the truck, the port side lights came on perfectly as always however, I noticed that the starboard side lights and tail lamp did not except for the first side marker, the one closest to the tongue of the trailer. Although the starboard running lights didn't work, the stop light and turn signal on that side did when you engaged them.

It was suggested to check the grounds on that side, which I did, since the ground for the middle side marker and the ground shared by the rear marker and tail lamp looked a little rough (rusted), I replaced both with new stainless steel hardware, bolt, washer, and nut. The main ground for the trailer was replaced two seasons ago, and remains in pristine condition. Unfortunately, the problem persists. I have checked the bulbs separately with a separate power source, and they all work properly. I even swapped the tail lamps, the starboard one worked perfectly (running lights, stop, and turn) on the port side. I have checked (tested) the truck electrical connections, and all function properly.

I'm stumped! http://www.bassboatcentral.com/smileys/doh.gif Please help.

Thanks in advance.


Modified by ClaudioFromOttawa at 4:17 AM 8/12/2010

I'd say it's wiring. The stop/turn has it's own wire. Usually the marker/tail light wire splits in the tongue with one wire down each side. I'd imagine yours is broken someplace right after the first marker light. I'd pull the first marker light and see what the wire looks like behind it.