When I had the oil changed on my 2007 Dodge Dakota, the service guy checked my battery and said it was “marginal”. He did not say that any of the cells were deceased. It is the original battery and I do lots of short trips requiring frequent starts.
But it has never failed and it never gets below freezing here in balmy southern California.
The service guy said that a “marginal” battery could actually harm the alternator. I have heard a much contested argument on whether charging a completely discharged battery will harm the alternator.
Is this true? Could a battery near the end of it’s happy life ham the alternator? Time for a new battery?