Originally Posted by
BlueKat
While the car is running, disconnect the battery. If the car dies, your alternator is bad.
Used to be done BUT since all the computers/electronics, NEVER do this!
Originally Posted by
ala_xfire
Yea, that's one way to do it, but NOT a good idea.
I prefer the 13.8-14.2 volts reading when running, 12.2-12.8 when off method though.
Plus 1
Originally Posted by
pizzaguy
THAT is dangerous advice. A voltmeter will tell you if the alternator is charging, but to disconnect the battery while the engine is running means that the alternator is driving the electrical system with no filter (an automotive storage battery is one HELL of a filter capacitor).
I don't see taking such a risk when a $30 meter from Lowes or any auto parts store will tell you what you want to know.
Plus 2
Originally Posted by
James1549
That could be one costly diagnoses...
Plus 3
.