No Brake lights/flashers/signals 75 Dart

You should have power to your brake switch and turn flasher.
Your brake light switch has power to one side then when you apply the brake pedal it sends power into your column through your hazard/turn signal switch.
Your turn flasher has power and when you turn the signal switch it completes that circuit ,there is a bi-metallic strip inside the flasher that heats up and cools turning lights off and on.
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I have a service manual for 1974 , not sure if 1975 is the same ? But for a 1974 A-body my FSM reads the following:
Fuse #2 should be power to the turn flasher .
Fuse #7 should be power feed to the brake light switch and emergency flasher circuit.

If your fuses are ok ( also make sure #2 and #7 fuse are getting power could be a feed problem into the fuse panel ) and you have battery voltage coming out of the fuse panel, then you have a break in the circuit somewhere.

Hands down the best tool I have ever bought to find an open circuit is the power probe ect2000.


[ame="https://www.youtube.com/watch?v=Ktsp6O9SiAI"]Spike TV Power Probe Commercial ECT 2000 - YouTube[/ame]