Ok, my electrical ignorance is showing again -
72 coupe, wipers not working. I noticed an electric tab near the wiper motor body with no connection.
If I run a ground to this tab, the wipers work.
What confuses me is this tab has a steady 12 volts going through it, even with the key off - is this normal for a ground connection ? I don't want to run a permanent ground to it and cause a short circuit or something ?
Ray
Adams' Apple
Wiper motors have 12v at the connector all the time. The wiper SWITCH is the ground. 9 times out of ten, the problem is the switch itself is not properly attached/grounded to the dash, thereby providing a good ground thru the switch. The "extra" terminal you see is probably for a wire from the blower motor ground. Myself, and others have sometimes added a redundant ground wire to the switch where it attaches to the dash bezel to make sure it is well grounded. I have some wiper troubleshooting stuff here somewhere...I think. Lemmie look...🧐
Joel Adams
C3VR Lifetime Member #56 
My Link 
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
I believe you are correct again !
I found a black wire nearby that had a proper clip for that terminal, so I unhooked the fan motor ground wire and did a continuity check, which I assume indicates that it is the same wire, or at least part of the same ground system. So I plugged it into the tab on the wiper motor. So far, so good.
I do use a battery disconnect when not driving until I get the wiring sorted out. And there is a fire extinguisher handy at all times, just in case.
