65 Cuda Part Two Rear turn signals

[Hemioutlaw]

Ok,
Wiring up the rear turns, brakes and running lights and have encountered a problem.
Everything works fine until I turn on the headlights and then the rear drivers side turn does not work.
I am testing doing this in steps with motor not running and ignition switch in accessory position and increasing the load with each step.
Step 1) Turn signals only, result = all work
Step 2) Turn signals with brake applied, result = all work
Step 3) Turn signals with brake applied and headlights on, result = drivers side rear does not work, pass.side does.
*** I do have an extra wire in the harness that was taped on the drivers side rear that does get intermittent voltage when the pass side turn signal is turned on?

I am testing these out of the tail light housings but I do have ground leads going to the aftermarket bulb sockets.

Could this be a wiring problem?
Turn signal switch problem?
Alignment of the planets and Alien interference?
Too many drinks, not enough drinks?
Seriously, doing this stone sober but am baffled.

Any thoughts or suggestions?

 

[Hemioutlaw]

Back in the spotlight

 

[B-onefan]

I have seen this before, Low on blinker fluid.

 

[Keith Mopar]

Could be a ground problem to that signal light, check the ground wire for corrosion.

Come on, if the blinker fluid was low it would happen all the time!

 

[B-onefan]

Could be a ground problem to that signal light, check the ground wire for corrosion.

Come on, if the blinker fluid was low it would happen all the time!

No, as you add more blinkers to the system, the fluid cannot return to the resevior fast enough and then the blinker fluid pump starts running dry, thus it starts drawing air and causing all blinking to stop. If that doesn't work, you may check the bulbs and make sure they are not broken internally on one side. Also make sure they are installed properly.