Help: 1955 Ford.   When I put the turn signal on during the day without headllights on everything works fine.  At night when the headlights or parking lights are on and when I put the turn signal on right or left the opposite tail light will be blinking but only very, very lightly, standing back you can see the blinking.  If I were driving behind me I would wonder which way is this guy going to turn.  Now the front parking lights work just fine.  If one is blinking the other is not.  I have the 6 volt system, negative ground.    Where do I start?      Johns55ford

JDH: 1955 Ford car, I have switched from 6 volts to 12 volts. Every thing working on 12 volts except now I have no brake lights, no turn signals. I have 12 volts at the brake cylinder. Where have I gone wrong? Turn signals worked on right hand side of car for a short time but quit.