Couple of weeks in now with my 72 Cutlass Supreme. Lights from interior, map, glove box, hood, trunk, instrument panel, marker lights, headlights, parking lights, courtesy lights were not working. Some were dead, others were missing parts, and all in order and working now.
I am now replacing with LED lights, and many times had to swap out the Sockets (rusted beyond repair). I have been checking continuity and power with every step and all good.
My problem, as with many are the 1157 tail lights. I have read that swapping the old flasher and hazard flasher out with new electronic ones would do the trick. But not quite.
My tail lights do not go on at all. The only time I can get them to light up is if I put only the parking lights on and put the turn signal on. Then it will light up only the side the turn signal is using.
I also read about LED load resistors need to be on each of the 4 connections to the tail lights, but figured I would ask some of the experts here first.
Anyone get around this issue, and if so, how did you resolve?
Thanks

 

You are doing the right things with your methodical approach, checking continuity and power.

When bulbs act strangely it is often the result of a ground problem, which you have been working on by installing new sockets.

Check the resistance between the ground side of each socket and the battery negative.

The load resistor solution only applies to newer cars where it's intended to defeat bulb-out warnings.

The signal and emergency flashers should be replaced as you indicated. They solve no-flash problems but can't solve odd, intermittent problems.

 

Thanks. If not too cold in the northeast today, I will get out there and do more troubleshooting. lol

 

Update: It was a ground problem. thank you! Only issue now is to get an Electric Flasher that works.

 

Final Update: Finally got the signal to work. Tried about 4 different electronic signals and all failed. If there is a 2 prong flasher that works, I could not find it. However, I was able to use the 3 prong, EP36. Had to switch the load wires and use the ground.



Video from Youtube below: