And even when it's running, you have to expect up to at least 16V, some of the cars and trucks with larger alternators will run a bit higher, I've seen 15V myse

And even when it's running, you have to expect up to at least 16V, some of the cars and trucks with larger alternators will run a bit higher, I've seen 15V myself but I've always heard that 16V is what to expect.