King,

Any charger will continue to pump the juice to the batteries, not knowing there is dead cell or two sucking the life out of the others. It's an easy answer with the Guest, if the red light is on for a prolonged time, you have a problem. I check mine after about 24hrs from turning it on to make sure it's in float (green light). Mango never looks in his engine compartment, he's too busy repairing whiskey dents.