I have relatively new wiring and dynamite sticks (6 yrs old) and correct 323 flasher and the tail lights have been working great until recently. I am using the standard bulbs (no led). The left side works correctly in all modes- stop, running lights and sequential flashing. On the right side the stop and running light function work fine, but the turn signal sequential flashing is intermittent. When the bulbs are cold, the inner and middle lamp light but do not flash and the outer lamp does not light. I have repeatedly checked the ground and that looks good. If the rear lights have been on for awhile and the bulbs are warm, all three bulbs light and sequence nicely. I am guessing the warm bulb has a higher resistance and that factors into the operation. I also checked for voltage on that socket with the bulb removed and measured about 6 volts.
Any ideas or suggestions are welcome.
Thanks,
Jim
I've owned my car since April 4, 1972 (about 4pm). I can tell you from experience that these lights are good one day and the next day you have a situation like yours.
For me, this was a solution.
http://www.virginiaclassicmustang.com/67-70-SHELBY-LED-SEQUENTIAL-TURN-SIGNAL-KIT-P2459.aspx
It is a very unobtrusive kit. It will fix all of the problems but has one shortcoming. It won't quick flash the brake likes in sequence.
If you are concerned with looking original, just leave the dynamite sticks hanging there in the corners.
FYI- The problem turned out to be a failing dynamite stick. The stick was a repop that was about 10 years old. When the turn indicators were cold, there was no voltage on the red wire powering the outer bulb on the passenger side. If the passenger side turn signals were on for awhile(like when I was trying to troubleshoot the problem), the voltage on the red wire came back. Replacing the dynamite stick resolved the problem.
Jim