Now before winter I charged my 5 year old AGM battery externally over night, because the tester indicated charging.This morning after the disconnect, the tester on it and then he said the battery is good. This afternoon I stuck the tester again and then he says swapping (exchanges), although the values are almost identical. Works everything, except on start stop, that works only after several 100km highway and then mostly only 2-3 days How does the test rate Should I be taking care of a new AGM battery?