When I turn my headlights on my brake lights come on. When headlights are off brake lights work like normal.
If you are sure they are your brake lights and not tail lights then I would check for shorted bulbs, filaments broke free and shorted to the other filament, bad sockets, damaged or shorted wiring in the rear lighting and don't forget to make sure the grounds are good. It seems like Asian vehicles wen they get a little age on them the grounds start to go away.
Had a loose wire to one bulb. Blew out the light sockets with air and replaced all bulbs. Crisis averted. Thanks
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