With the multiple unrelated warning messages, that could indicate weak, failing battery(s). You should get both batteries checked. Be sure they are not connected when you have them checked or the results will be for both batteries.
Check both batteries again. If you replaced the main without changing the aux, if the aux was bad, it could have been bringing down your new battery as they are connected when the vehicle is off. If this goes on long enough, it can kill your new main battery.
I would do this before ordering a part that you may not need.