Not positive on 55 but a 56 has 4 wire’s going to the back of the car. They start under the dash are on top of the trans hump, slide over to the drive shaft hump on the left side, are clipped under the rear seat and enter the trunk on the left side over the wheel well, on to the trunk left edge to the left tail light area.
I advise everyone to purchase a laminated 11 x 14 wiring diagram from classiccarwiring.com if your wiring is original the diagram is color with every wire labeled. 

56 Vic, B'Ville 200 MPH Club Member, So Cal.

Taillights work off the headlight switch.  First, get a test light and see if there is power at the wire at the taillight itself.  If not, trace the wire to the headlight switch and see if power there.  If you have power at the switch and not at the taillight, then something in between is the problem.

To find out what wires go to the switch, note the color and tracer  and find the same color and tracer at the switch.  There should be one wire going to the back (serves both lights). A wire schematic helps if you have one.

If it's the signal and stop lights, then it's a whole different setup.


54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

HI guys. Coming home last night, I had cars flashing their lights on me. When I stopped for gas ai checked out the back end. Found I didn't have any taillights. Everything else was working, directionals, brake lights, headlights, dashboard lights all interior lights. Changed bulbs in the rear this morning. Looked for loose connections, found nothing. Could it be the switch. Any Ideas Thank You.