72 Demon playing the juice harp and brake light misery

[ro23dart]

So i have a couple of problems, probably not related but both electrical. The first is that my dash seems to be playing the juice harp every minute or so. I get a metallic "thung" that seems to be coming from the wiper switch. If its not it is close by, i can feel it strongly when i'm touching the wiper switch. This car is supposed to have the 3 speed wipers, i'm not sure that the switch that is in it is for a 3 speed, or if they are even different switches.

The second problem is the lack of brake lights or hazards. Turn signals work fine. I checked the brake switch and it works, passes voltage to the white wire at the connector. From there i have continuity from the other side of the connector to the white wire on the turn signal switch and no short. If i plug the connectors up though i get no voltage at the switch and i have continuity to ground. Short at a bulb maybe?

Any help or direction you guys could provide would be greatly appreciated, i'm a little tired so i probably missed something obvious.

 

[RedFish]

My best guess for the noise ( if only when wipers are running ) is wiper linkage. We've seen pics of cases where someone had replaced the proper bushing with nothing more than a retainer clip of some sort. Result is metal to metal movement and lost motion.
The turn signal switch should send brake lamp current ( from white ) back out on 2 wires when its in centered position, when the brake lamp switch is closed. The switch changes the current path to one brake and one rear turn when activated for left or right turn.

 

[ro23dart]

Ok, a little update. I unplugged the connector on the wiper switch and the weird noise stopped. Problem solved for now, i need to take the car on a shakedown run before i worry about wipers anyway.

Next i unplugged the TS switch connector and jumpered the white between them. Boom, 12v at the switch. Then i jumpered the brown and dark green wires and no voltage. Unplug the dark green and i have voltage again. Then i plug it back up and pull the bulb on the drivers side rear and i have voltage. I'm thinking a short in the bulb plug or somewhere down the line? Maybe it is shorting out through the bulb? Still kind of weird that the turn signal on that side works but now that i think about it the passenger side was much brighter.

 

[ro23dart]

Alrighty then. Turns out it was a bad connection at the fuse box. It would carry voltage as long as there was no load on the circuit. As soon as i applied a load the voltage disappeared. I used a bench power supply to power the circuit starting at the kick panel connector and backtracked to the switch connector, brake light switch and then fuse panel to find the problem. Figured i would post just in case anyone encounters a similar problem.

 

[RustyRatRod]

What's a juice harp? Do you mean Jew's harp?

 

[ro23dart]

Haha, i just googled it. Turns out thats another name for it! Learn something new every day. I wonder if its a regional thing?