Mark,
Not so...
A fully charged Lead-Acid battery will show 13.8V at no load.
Under charge it can go up to 15V.
A fully discharged battery could show anything between 11V to 6V and
even lower depending on the condition of the battery..
A voltmeter can indicate when you have a dead or shorted cell.
It can also be an indicator of the condition of your system when it
momentarily drops from 12V to around 6V on cranking the starter...
There are a few other things I could think of... but that's enough to
start with.. :-))
Dave G.
> the voltage difference between a
> charged battery and a discharged battery is only about 2 volts which
> is hard to see on a analog car voltmeter anyway.
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