Turn signals not working

Passanger side turn signal works erratic. When the brakes are applied the passanger side turn signal blinks fast, also the back up lights come on on both sides but are dim.I switched the rear brake light assembly to see what happened and it done the same thing, but everything on the driver side works correct except for the back up light lighting up when the passanger side turn signal is on and the brakes are applied, I have changed several bulbs to see if that would help, nothing changed.I also made sure all the bulbs were correct