Tail light / turn signal wiring issues

[fredsfiat]

My Spider ('79 2000) was disassembled for body and paint work and in the process of re-assembly, I find that the tail lights are doing some weird things now. When the engine is on and I turn the turn signal to the left, the turn signal light seems to work appropriately. When the engine is on and I turn on the lights and then turn the turn signal to the left, the right turn signal light alternates with the rear tail light to the cadence of the switch. When I turn the turn signal to the right with the lights on, nothing happens. All of the bulbs look good. Also, the license plate lights are not coming on at all now. Have not checked the bulbs yet, but they were working after re-assembly at first. What should I check first? Any suggestions would be greatly appreciated.

Fred

[vandor]

Definitely some grounding and connection issues. Those circuit boards can be a huge pain.
I would start by making sure everything gets a good ground.

[spider2081]

I agree on the grounds. In addition be sure the plastic covers have been put back on the marker plate light spade connectors. I have seen a few cars with them missing and that allows the light wire to short to ground. If that happens it burns a PC land off the drivers side light PC board.

[fredsfiat]

Thanks for the advice. I will start with the grounds and let you know how it goes.

Fred

[jkn070458]

My 78 lights all worked, every thing! Did a bulb check and one of the rear turn signal lights didn't work. Nuts. Using a power probe I found that the usual amount of corrosion after 35 years ha taken it's toll. I had clean powers and grounds to the wires (no voltage drop) but it wasn't reaching the bulbs. I removed the tail light assemblies and took them apart. It's not easy unless you have all the right stuff and skills on hand.

First you have to drill out the rivets to remove the socket, nest your get a pocket pry bar and take apart the socket. Note the way it comes apart. Now you can remove the copper ribbon (power) that contacts the bottom electrode of the bulb. Take that to the wire wheel and CAREFULLY whiz off all the corrosion and put the socket back together.

At this point you have 2 choices, get the right size rivets and re rivet the reflector back together or use some small screws to do the job. I did it both ways since I have all this stuff in my shop but it was easier with the small screws (the screws I used were in my bins for the last ten years and really fit nice without splitting the plastic. The first one took me about 45 minutes and did all 8 sockets in about 4 hours!
Tedious but boy do I have bright bulbs!