Power to accessories

Has any of the OEM wiring been modified at all? Seeking clues LOL
Brake lamp circuit which is hot at all times can short to turn in the turn signal switch. I think a bad hazard lamp switch can short and back feed the same way.
A back feed would power all 3 of those hot only in run fuses but... this wiring is undersized for powering wipers, blower, etc... A melt down would occur eventually.
One method you might try... Find the black hot in run wire going into the fuse box, pull it from that buss bar. It should have no power if ign' switch is in off position. If it is hot the short is that wire back in the harness somewhere. If not hot/correct, now check that the buss bar is hot. If it is, pull fuses 1 at a time to determine which circuit a back feed is coming from. That's the best I can offer at this point.