My tail lights work and my passenger side brake light and turn signal work but the driver side brake light and turn signals do not. I have replaced the bulbs and still having the same issue.

$1 tester made in china, open the rear tail light, take out the light bulb, ground the DC tester to a chassis bolt, turn the ignition on, flip the turning signal handle to the turning location and touch the inside socket filament, one side at a time, if no juice, your steering wheel turning signal is damage and it's only working on one side. Good luck

one side of the inside socket contact filament will produce light on the screwdriver type $1 tester, it's not dangerous, the other side will not turn the tester light one, this one is the grounded, this is if the turning signal is working. The brake pedal switch is another component not associated with the turning signal, it's independent, it goes behind your brake pedal arm that releases the switch on when the brake is applied.