2017 S60 Inscription - 40K miles, bought a new battery 2 years ago (16K miles). Started getting an SID message of "Low Battery Charge". I checked the battery charge and very strong, but with my limited skills/knowledge, when I had the engine running and checked the charge, it was on the low end of "OK". Anything else a novice can check before I hand over to a professional? I don't have a trusted pro yet as I bought the car 2 years ago and everything has been covered under dealer.

Also - trusted Volvo shops in the Long Beach / Seal Beach / Huntington Beach CA area leads appreciated.