Weird Brake/Lights Problem

[Techrangerbrad]

I was out Memorial Day Weekend with my ol' Niagra (RIP).  We started out and after a mile or so, the brake lights would not light and when I hit the right turn signal the two way flashers would come on. Also, using the brakes had no effect on the trailer brakes, but I could manually use the brake controller to brake the trailer.  If I am not clear enough, please feel free to ask clarifying questions.  What is interesting is I have the same problem with my "Beast" - Avalon.  It works for about a mile and then the fun starts.  I am not sure if I have a loose fuse or what the problem could be.

[pgandw]

I was out Memorial Day Weekend with my ol' Niagra (RIP).  We started out and after a mile or so, the brake lights would not light and when I hit the right turn signal the two way flashers would come on. Also, using the brakes had no effect on the trailer brakes, but I could manually use the brake controller to brake the trailer.  If I am not clear enough, please feel free to ask clarifying questions.  What is interesting is I have the same problem with my "Beast" - Avalon.  It works for about a mile and then the fun starts.  I am not sure if I have a loose fuse or what the problem could be.

Since it happened with 2 different trailers, there is a problem in your tow vehicle wiring, most likely between the towing plug and where it taps into your TV tail lighting.

Without knowing the specifics of your TV, and whether it came with a built-in harness or the TV wiring was done by an after-market installer, I am only guessing.  If you have the orange turn signals on the TV, I would suspect the converter package that combines the separate turn and brake lights on your TV (3 wires) into a single pair of lights on your PUP (2 wires).  A check would be to disconnect the PUP electrically and test the TV lights alone when the problem occurs.  If the TV lights are fine, the problem is likely the converter.

Another possibility (less likely) is TV hitch wiring that has frayed insulation and wires are shorting against each other of the TV frame.  Symptons would depend on which wires specifically, and probably would affect TV tail lights when the problem occurs.  I once blew a TV turn signal fuse when the boat towing plug and wiring got pinched and cut off as the bottom of the hitch receiver hit a speed bump.

just my thoughts
Fred W

['tiredTeacher]

I was out Memorial Day Weekend with my ol' Niagra (RIP).  We started out and after a mile or so, the brake lights would not light and when I hit the right turn signal the two way flashers would come on. Also, using the brakes had no effect on the trailer brakes, but I could manually use the brake controller to brake the trailer.  If I am not clear enough, please feel free to ask clarifying questions.  What is interesting is I have the same problem with my "Beast" - Avalon.  It works for about a mile and then the fun starts.  I am not sure if I have a loose fuse or what the problem could be.

Sounds like a ground problem in the wiring harness on the TV.