Bought a car in auction. Now seeing these on the dash

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.

I still suggest getting the batteries checked. You will find many threads here on weak batteries causing all kinds of electrical warnings when there is actually nothing wrong with the actual features.

And if you are still covered by the 3/36 warranty, they will be covered if they fail the testing.

How long ago did you change the main battery?

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.