Wiper switch circuit breaker and a jolt

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64longroof

64longroof

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1964 dart, push button, auto. Recently reassembled the dash with new wire harness.....only driven car half dozen times, but last time I got a good jolt when I lifted the park lever. While trying (unsuccessfully, of course) to reproduce this apparent short, I could hear a very faint sound that can be best described as grinding, for a second. Then it sounds like the wiper switch circuit breaker , I assume, cycling on and off about every five seconds. "Boing, click."
I tightened the wiper switch retaining ring, thinking the switch had a poor ground.
No change.
It may be that the circuit breaker sound and the jolt I got are not related.
I also add that the wipers are not working, not are headlights....acc fuse is tested ok.

I wonder if the whole shift mechanism is supposed to be grounded /isolated from dash metal?

Any suggestions what might be going on?
Thanks.
 
The cable or mechanism could be rubbing against a uninsulated cable.
 
12 volts won’t shock you, so it has to be something else. I would think that you may be on to something with the wiper motor. If the wiper motor is on and stuck, it would pull a lot of current. When the circuit breaker opens, it breaks the current flow. When you break the current flow on an inductive circuit like a motor, the voltage rises to to try & keep the current the same. This is how your ignition system works.

I bet the timing was just right with you touching the shift lever & the breaker tripping. The voltage must have found a path to the lever.
 
Mike69cuda said:
12 volts won’t shock you, so it has to be something else. I would think that you may be on to something with the wiper motor. If the wiper motor is on and stuck, it would pull a lot of current. When the circuit breaker opens, it breaks the current flow. When you break the current flow on an inductive circuit like a motor, the voltage rises to to try & keep the current the same. This is how your ignition system works.

I bet the timing was just right with you touching the shift lever & the breaker tripping. The voltage must have found a path to the lever.
Click to expand...
It's either 12 volts DC or 15,000 volts dc from a plug wire.
 
toolmanmike said:
It's either 12 volts DC or 15,000 volts dc from a plug wire.
Click to expand...
Mike its past 4:20 what have you been smoking?????:poke:
:rofl:

50973.jpg
 
Dana67Dart said:
Mike its past 4:20 what have you been smoking?????:poke:
:rofl:

View attachment 1715977204
Click to expand...
Mike69cuda said:
12 volts won’t shock you, so it has to be something else. I would think that you may be on to something with the wiper motor. If the wiper motor is on and stuck, it would pull a lot of current. When the circuit breaker opens, it breaks the current flow. When you break the current flow on an inductive circuit like a motor, the voltage rises to to try & keep the current the same. This is how your ignition system works.

I bet the timing was just right with you touching the shift lever & the breaker tripping. The voltage must have found a path to the lever.
Click to expand...
"12 volts won't shock you so it has to be something else"
 
Put one finger on positive post and one on negative post of your car battery & see what happens. Nothing….
 
toolmanmike said:
"12 volts won't shock you so it has to be something else"
Click to expand...
Mike69cuda said:
Put one finger on positive post and one on negative post of your car battery & see what happens. Nothing….
Click to expand...
agreed BUT...

Load up a starter motor and break the feed wire while touching ground and the post and guess what... ZAP.

a coil winding of a motor is very much like an ignition coil. That's what Mike69cuda was trying to point out.

Mike69cuda said:
2 volts won’t shock you, so it has to be something else. I would think that you may be on to something with the wiper motor. If the wiper motor is on and stuck, it would pull a lot of current. When the circuit breaker opens, it breaks the current flow. When you break the current flow on an inductive circuit like a motor, the voltage rises to to try & keep the current the same. This is how your ignition system works.
Click to expand...

Ask me how I know about the starter motor!:mad:
 
Mike69cuda said:
12 volts won’t shock you, so it has to be something else. I would think that you may be on to something with the wiper motor. If the wiper motor is on and stuck, it would pull a lot of current. When the circuit breaker opens, it breaks the current flow. When you break the current flow on an inductive circuit like a motor, the voltage rises to to try & keep the current the same. This is how your ignition system works.

I bet the timing was just right with you touching the shift lever & the breaker tripping. The voltage must have found a path to the lever.
Click to expand...
Yeah. You keep thinkin that. LOL I used to think that too, but I've been proven wrong on many an occasion. If it's a big enough amperage circuit, it can give you a jolt.
 
Ever been working on your car on a hot day and sweating ??? Then lay your inner forearm across both battery posts. It won’t be ‘too’ bad, but can still get your attention.
Yote
 
Yote said:
Ever been working on your car on a hot day and sweating ??? Then lay your inner forearm across both battery posts. It won’t be ‘too’ bad, but can still get your attention.
Yote
Click to expand...

Yep, same thing with a 9V battery on your tongue. Skin resistance is about 1000 ohms dry, drops fast when wet.

Sitting on a vinyl car seat & touching a piece of metal takes a little more voltage to get a shock than 12V.

My comment was just a theory, I have no evidence.
 
What does the jolt feel like? If you can get "wet enough" or an injured finger, 12V burns not tingle. A "jolt" is either spark or the primary of the ignition coil, or a relay coil "kick."

Possibilities: tach wire, horn relay (button) circuit, any other relays you've added like driving lights that are "near" the column physically or wiring / electrical.

It also might be something REALLY far out like.............You said grinding noise, HOW ABOUT THE STARTER

Maybe the engine block is not properly grounded, and something caused the starter to attempt to engage.

I "did that" once in my old 70 RR I had the battery trunk mounted, and had been doing something --I think a cam change-- somehow the frame / body to block jumper got not reconnected. First time I tried to start it, mucho sparko's came from the clutch linkage and CRAPPED A CLUTCH LINKAGE RETAINER CLIP right out on my foot!!​
 
It might be possible for a running motor like the wiper motor to jolt you but I just can't see this getting "wound up" in the column/ linkage. "Inductive kick" generally, is one term by which this is known.

You can get a "mini jolt" from an older analog ohmeter. I don't know if a digital will. You can get this by attempting to check a motor winding or transformer winding, while holding onto the leads with your fingers.
 
Just like the jolt you get from a push lawn mower.

Prior to this shock , I did disassemble the wiper switch to see if all the contacts looked OK. Looked good, but could I have reassembled it wrong, in a way that would cause the breaker to keep tripping?
 
Is your wiper knob set up for "push to wash?" What is that connected to? Normally it operates the small pump motor on the washer pump assembly
 
Weird things can happen with high voltage. It doesn’t follow the obvious path sometimes. If it is an inductively induced voltage by stopping the current in a winding, the voltage will rise until it finds a path.

Could it be static electricity that shocked you? Similar to walking across a carpet and touching a doorknob?

Taking switches apart can be a challenge. Could be very likely that it didn’t go back together right. Does the circuit breaker still pop with the switch unhooked? Does it pop with the wiper motor unplugged?
 
Closer inspection revealed that the grinding was the wiper motor attempting to turn. But if I wiggle the wiper knob to the right place, the wipers will run strongly. Not sure if that means the wiper contacts are not quite lined up, and so not enough current is moving to the motor, or the motor has some kind of binding issue. Once they start moving they stay pretty strong and I don't see any physical contact of the wiper mechanism arms or pivots with other items.
Anyway, this would explain the breaker tripping and resetting . It might also explain a voltage build up that somehow got transferred to the parking lever. All I can think is that some of the foil backed insulation I added somehow connected between the wiper connecting arm and the top of the gear select/park assy. Which is scary, because electricity should not be able to move from the motor to the mechanism.
The other clue is that the rheostat seems to work, as my test lamp decreases in brightness as I turn the wiper knob, but I get no variable speed. Seems like the only power that moves the motor is in the black/blue connector to the motor.
 
I opened switch up to inspect it after outside of it was slightly charred in a fire. Probably reassembled it wrong, as the motor runs when knob is in off ( fully ccw) position. Why I didn't take photos.......?
 
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