discharge/overcharge?

One thing to note also, is that there is a big difference between volts and amps as to how they show on a gauge.
My Dad always told me I should use amp gauges instead of volt gauges, and my argument was that I didn't care what the draw or state of charge was but more the system total volts available.
Lack of amps is a lot easier to track down (diagnose) usually that a lack of volts.
It always has been for me anyway.