Alternator charging issue

[dcdoug]

I have a battery charging issue that I'm struggling to fix.

A bit of background, because this has been a complicated issue:

First, I had problems with the car starting (out of the blue, not because I made any changes). The solenoid tested bad and was replaced. Then the ignition switch stayed in the "on" position and ran down the battery and that was replaced. Then the start circuit seemed to work, but the battery stopped charging. I will say that right before all of this happened, I briefly saw a weird "ticking" of the ammeter while it was showing charge (while driving), but the needle would tick back to the middle neutral position. I haven't seen that before. Next day, car wouldn't start and the above happened.

It feels like I must have a loose wire somewhere, but I've checked all the obvious ones and they are tight. The car starts fine, but the ampmeter shows discharge when it's running and the fans are on. I have confirmed with a multimeter at the battery that the battery is not being charged.

I have had the alternator tested and it's good. I replaced the voltage regulator. I checked connections under the dash and they seem tight (I tightened a few). I did not remove the dash, but crawled under it, so it wasn't a thorough inspection as space is tight and I could have missed something.

The only other clue I have is that when the starting problem went away and changed to a charging issue, the "on" ignition light stopped working, which seems to also be referred to as the "alternator problem" light. The bulb visually appears Ok, but I have ordered a replacement. The wiring diagram shows that the other side of this connection is the "I" terminal on the voltage regulator. I find it hard to believe that a bad bulb would be a cause of this problem and is more likely a symptom. I can say that with the bulb installed, there is no continuity between the two leads going to the bulb and it seems like there should be.

Thoughts?