Does battery lght go on when alternator is bad?

Yes the battery light does come on, but to be really sure you should get
yourself a meter (very inexpensive these days about $15 for a digital meter
in an automotive shop) and do a little troubleshooting. First measure the
voltage across the battery terminals and it should measure about 12.8 volts
if it is charged. If the battery is fairly new and it is less then 12v then
the problem could be your alternator not keeping it charged. If the battery
has enough charge to start the car let the motor run and measure the voltage
across the battery terminals again and the voltage should read about 13.5
volts. This tells you that the alternator is working. If it measures less
then what you measured in standby then there is something wrong with the
alternator. More then likely the regulator inside the alternator is gone.
if the alternator is bad you will have to get it fixed or buy a rebuilt unit
and replace it. Buy one with a lifetime warranty because Saturn alternators
are prone to failure. I have changed mine twice already in five years. When
you have found your problem you will have a good tool to help you in the
future with any other electrical problems instead of playing the guessing
game and buy parts for nothing.
Alex
"wreckingballs 2" > wrote in message
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