I found a really good deal on a Can Am trailer hitch so I bought it thinking i might someday buy a trailer. Someday has arrived and I can not for the life of me get the trailer lights to work. I purchased the Show Chrome harness which is 5 wire out. The trailer has a 4 wire flat so I purchased a 5 wire to 4 wire adapter and the only thing that works on the trailer is the tail lights, no brake or turn. What have I missed. Did I get a bad adapter or is there something else that could be wrong? 2011 RT SM5