Toyota Repair: Trailer lights for 1998 4Runner, hardwired system, toyota factory

Question
I noted your answer for no trailer lights on a 1999 4Runner. My 1998 4Runner has most trailer lights working except right side Brake and Turn Signal. My Toyota dealer suggested I take it to UHaul. UHaul was very gracious. They determined that all fuses were working. They thought that there was a "module" somewhere that was most likely problem, but they thought the module was behind an interior panel in the back so the referred me back to Toyota. They said they could tap into the rear lights but they thought it would be preferable to get the hardwired system working. Thanks a lot. Brian

Answer
Does it have a toyota factory trailer hitch and the wiring or is it an aftermarket unit? If it's the factory installed unit then the entire towing harness with the converter should be replaced, most of the time the converter box is the problem but it is not available seperately from toyota, if it's an aftermarket installation it may be available in which case I think the U-Haul store would have been able to fix it so I tend to think it's a factory installed hitch and wiring.