Three electrical questions - 68 Fury III Convertible

[Julesva5]

All - hoping someone can help me here who has troubleshooted this issue. I have a 68 Fury III Convertible, and the interior dash light/down light does not turn on when I open the door. Dash lights themselves do work, and I pulled the door switch and it seems fine. I can get the down light to turn on when I pull the frame out that it sits in, but as soon as I start to screw that frame back in (e.g., ground it) the light goes back out. Also - my trunk light is not working, so I'm assuming maybe something that's related - I have put in all new bulbs of course.

Second question is regarding LED lights. I put them in the tail lights, but as soon as I do that, the turn signals do not work - just turn on and stay on. Is there some type of different flasher needed here to use LED? It's not a big deal as I can use the incandescent ones, but I like the brighter quality of the LED's.

Finally, my four-way flasher is not working at all. Is that the switch or a relay or...?

Thanks for the help here!!

 

[Mopars & Missiles]

The LED's are causing your turn signal and 4 way problems (provided they worked fine before). There is very little electrical load on the factory flashers when you convert to LEDS. You need to change the flashers (both of them) to electronic ones suited for LEDS.

Something like this from Summitt will solve that problem.
United Pacific LED Flashers 90650

 

[Turboomni]

Just to add to the confusion I installed LED tail lights to my 69 Fury. Tried the leds on the front too but did not like the running lights were dim. Put the Edison bulbs back in the front and the turn signals were fine and brighter because the rear lights pulled a lot less current.

 

[Mopars & Missiles]

Just to add to the confusion I installed LED tail lights to my 69 Fury. Tried the leds on the front too but did not like the running lights were dim. Put the Edison bulbs back in the front and the turn signals were fine and brighter because the rear lights pulled a lot less current.

I did the same on my '69 B body. I believe with the front bulbs (as you say "Edison bulbs") used in conjunction with the rear LEDs, you are pulling "just enough" current through the turn signal circuit to trigger the bi-metallic factory type flasher and make it work. A little 'less' current and the factory flasher ceases to work. Its just a matter of whether you are 'above' or 'below' that current threshold that you may need to switch to the electronic flasher previously mentioned. The factory flasher doesn't care about LEDs or Edison bulbs, all it cares about is enough "current draw" to operate properly.

 

[Julesva5]

Thanks all - that's definitely the issue with the LED's then. I purchased the electronic flasher to solve that one. However I still have the problem with the four-way flasher not working and interior light/trunk light not working when grounded. Any ideas there? Is the four-way flasher the same as the turn signal ones (and I just noticed I need two of those I guess)? Or is it perhaps just the dash switch itself? Thoughts?

 

[GregG48203]

I still have the problem with the four-way flasher not working and interior light/trunk light not working when grounded

IIRC, the '67 & '68 Furies had a 3-position switch for the map/dashboard light: ON all the time, ON when you open the door, and OFF. This is where having a FSM (factory service manual) with wiring diagrams is handy. The trunk light works the same as the door switches: switch closed - light goes on. If you inadvertently ground the wrong wire, you blow a fuse.

 

[Julesva5]

All - thanks for the help here. Turns out that when I was able to get up under the dash the four-way flasher was just disconnected! Easy fix and with the new electronic flasher now installed I have successfully converted the rear lights to LED. All works fine! I tried LED's on the front turn signals but found the incandescent bulbs look way way better so I kept them.