Charging system troubleshooting

RBConvert said
You got it. This schematic illustrates how I tested the VR yesterday. Bad wire connection - you mean with the jumper? I'm going to try to duplicate it again tonight.

Maybe - I was thinking more like the splice or connection when the second wire was added (by previous owner).

For example if either of these connections is loose.

RBConvert said
I'm not familiar the "blue" VR.

Mopar Performance sold (sells?) blue painted electronic regulators. The one I mentioned was for alternators with one field terminal grounded. I'm pretty sure they also sold one for isolated brushed alternators like you have. Had the same triangular connector as a factory regulator.

RBConvert said
The current VR on the car is a NAPA Echlin. Don't know if this makes a difference: the current VR has a smooth face; the two replacements I found (cheapo Chinese and an ACDelco) have a slight step-down on the face.

I haven't had to experiment with buying these. The most recent AC Delco item I bought was an alternator for my Wagoneer. QC was not there - would have flagged a major problem if this was a GM production item. parts store exhanged it and we got an older one that was fine. It's crap shoot out there.