i recently replaced the turn signal flasher/relay in my car along with the hazard flasher/relay in my car hopeing that the malfunction would stop, but all the brake lights like to light up when i use my turn signals. the signals in the front work the way there supposed to but everything in the back blinks as well. also if im using turn signals and applying the brake, my doors like to lock/unlock as well. and i've fixed all the grounds in the front of the car in the engine bay but i cant seem to find the ones in the back of the car. im thinking that could also be a problem.
why do both tail lights and third brake light blink when turn signals are used? on 1994 Chevrolet Cavalier