Odd Brake System light issue

[str12-340]

I installed a whole new original style KH disc brake set up with power booster in my 1970 Dart - all new lines, calipers, wheel cylinders, hoses, brake hardware in the back, pads shoes, etc. When I turn the key on ('run') the Brake System light on the dash comes on and it stays on when I push the brake pedal. When I start the car, the light remains on until I step on the brakes, when it goes off. The brakes seem to work fine. When I hit the brakes with the car running and the light goes off, I can pull the emergency brake on and the light comes back on, as expected. I have 2 other 1970 Darts and the light only comes on when I pull the emergency brake on (and hopefully if half the system fails, but it never has). The "proportioning" valve ( distribution block) where the wire for the brake failure plugs on is new, as is the M&H wiring throughout the car.

Any ideas what might cause this?

 

[4spdragtop]

Mine comes on/off in our 67 cuda, loose connection at the switch by the handle. I havent climbed under(yet) to dbl chk.

 

[Murray]

Pull the wire to the distribution block and try again.

 

[Oldmanmopar]

I just wired Todds Barracuda rally dash. The light comes on with the park brake. And with a brake failure. I also wired it to a oil pressure sending unit so if the pressure drops the brake light comes on. So the light is always on with the key on but goes out when you start it and the pressure builds. The car now has a gauge and a light. So if the pressure drops there is a light to warn you to check the gauge.

 

[Dana67Dart]

The spool In the brake warning system ( in the distro block) should have 2 springs to keep it centered.

Most likely one spring is weak or sticking and the spool is too close to one side or the other.

The factory service manual has a cutaway.

Short of taking it apart and cleaning everything, you MIGHT be able to get it more centered by bleeding the front or the rear to move the spool.


It should not be necessary.

As Murray said you can prove it is not a wiring under the dash thing by disconnecting the wire on the distro block and putting things through their paces.

If no abnormal lights it's the distro.