Here is a thought abouit the possibility of gremlins.

Corroded connections in the connector that connects the pcm harness to the body harness, just inside the firewall on the passenger side, behind the kick panel.

Your wire that turns on the voltage regulator (comes from instrument cluster) is a small guage red wire that connects to your engine pcm harness through a small white connector ( 10 pin connector with 2 vacant pins) or mine is anyway).

I had a few weird electrical issues that traced back to this connector. A few wires had begun to turn green with corrosion. I hard wired around the connector and all was good.

Hope you find your gremlin!

Keith

 

I replaced the pigtail for the alternator and have not come across any more issues with charging. Thanks everyone for your help.

 

I am reviving an old thread. I have a similiar problem.

I had an alternator stop charging. I took it to O'Reilly's and it tested good.

I then chased all the wiring and never found a problem with any of the wiring....at least nothing obvious.

Gave up and bought another alternator and instantly the car was charging again......but only for a few days before the new alternator has stopped charging.

I am getting 12v at both the exciter and charging wire on the alternator. I am also getting 12v at the dash cluster.

Any ideas what could be going on here? Am I burning out alternators with some wiring problem or just another bad alternator?

Any idea would be appreciated.

Thanks,

James

 

Have you checked your grounds? Have any wires been replaced before? My problem was similar and I replace the alternator pigtail, it testes fine, but when the wire was plugged in there was no connection, due to the cable location. It didn't really show any signs of corrosion, but it was one of the last things I could replace.

Hope this helps