I recently pulled the motor and put new seals, gaskets, etc. and after putting everything back together I had a HUGE electrical problem. I had bad/ no charging and all kinds of warning lights.
After removing the Negative battery cable with the key off, I had 6V running through the body.. Something was still on.. or? Bad ignition? Relay? Bad Ground?
After much trial and error I removed the Positive Cable and STILL found 6V. (neither +/- cable hooked up)
I eventual completely removed the battery and found that this was all because of a dirty battery running current to/ through the body. I never had any issues before the pull and it was a black battery so it wasn't obvious.
Problem: Now my exciter wire is only putting out .6V.
When I first pulled everything I pulled out the alternator without discounting the exciter and pulled the wire right out. I was oblivious to the pulled wire and after putting everything back together ran it with the wire dangling. (ROOKIE MOVE) It may have hit ground. I found one article that said the Exciter starts with low voltage and then rises. Is this a result of a alternator signal or something else? Fried my PCM? I get a great charge if I touch the exciter with direct battery voltage. And I also checked/ Cleaned all the wiring under the battery.
2000 Z28, Was A4, now M6. No other wiring modifications.