Hmm. Not sure what part of a wiring diagram you're looking for... As far as I know, the Solera 7 way does not include a separate brake light output. Some (all?) brake controllers use the combination of both left and right turn signals to indicate brakes on. (So they probably think four way flashers are brakes going on and off...).
Some wiring diagrams have been posted (for recent R and W models, I think) but I don't think they include details of the 7 way connector as that is run largely by a separate controller which is supposed to isolate the Solera wiring from the toad wiring...