I have a 1995 Passport. The brake and low fuel warning lights started coming on when I was driving on the highway. From what I have read, this usually means that the alternator is bad. On the way to have the battery and alternator checked, I noticed that before the warning lights came on, the battery would drop from around 14 volts to around 9 volts. This would happen around 3000 rpm.

I had the battery and alternator checked and both checked out fine. The guy said that it might be the voltage regulator.


If the voltage regulator is bad, will the alternator check ok? Is there anyway to trouble shoot it?

 

the voltage regulator is in the alternator. This would mean the alternator is bad. Which is also my guess as to the problem. The voltage drop could only be explained by a bad regulator.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Evil Monkey &raquo;</TD></TR><TR><TD CLASS="quote">the voltage regulator is in the alternator. This would mean the alternator is bad. Which is also my guess as to the problem. The voltage drop could only be explained by a bad regulator.</TD></TR></TABLE>

Right but when the alternator was checked the guy said it checked out. It may have checked out because their tester is set to test at 2000 rpm and mine does not have problems until around 3000 rpm.

Thanks for the reply. It looks like I will try a new alternator. I can buy a rebuilt alternator for the price of a new voltage regulator.