My multi gauge in my 72 will not stop flashing
First thought was that I needed to reset the master cylinder after the breaks were done. I did that - Still flashing

I checked the switch on the emergency brake. I had connected one of the wires for the back pad light to it Fixed that
- Still flashing

I was blowing a fuse for the drivers side signals. After reading posts I thought this could be indicating I had an issue with lights. I tracked down the ground, fixed the problem - Still flashing

I had replaced almost all of the lights in the dash with LEDs. So after reading posts about how the flasher relay works, I swapped these 2 lights and the turn signal lights in the tac back to regular bulbs - Still flashing

Any ideas?

Below is the circuit for the turnsignal/brake warning flasher system for your car. On the right side, notice the brake warning bulb. It connects to the brake master cylinder switch and the e-brake switch.

Try disconnecting the wires to one of the switches then the other to see which one is providing the current path to ground for the warning bulb.

Yep.

If the wires are reversed on the MC switch it will do what yours are doing.

Also check all the ground wires.

Good luck, I had this same problem.

My car’s 2 wire master cylinder switch was faulty, I could not make it stop flashing until I converted it to a 1 wire switch.