my ammeter always read 14 with my old set up and my fusible link wire was always HOT. After fixing some resistance points and the addition of a new alternator, that ammeter barely settles much above 12. (same gauge)
A ammeter reads amps and the one built into the dash should be streight up to slightly to the right when the engine is running. If you turn on the head lights and apply the brakes at idle the indicator might go slightly to the left of center.
If you are doing as I asked, you are using an external volt meter to measure voltage between the positive and negitive posts on the battery.
