I am having major problems with 89 PAthfinder charging. To start with the alternator was putting out around 16 volts. Had it tested at Autozone and they said it was bad. Bought a new one and it was also overcharging. A couple hours later started it up and it looks like it is not charging at all. Only shows 12,3 volts at the battery with engine running. The alternator indicator on the dash does not come on when the ignition is turned on I could have gotten another bad alternator but was wondering what else might cause this problem. Thanks in advance for any suggestions.