2019 XC90 with 200 miles
sat for 2 days after bought it. and when I started gave me charging fault message.
I fully charged the battery over night from the front outlet.
message did not go away in the morning, went to dealer, did software update, message went away. said battery is good, just software needed update.

The message is gone now. I left the car for one day in the garage after that (locked, and keys away), the next day unlcoked car (may have small voltage drain with lights, chair, etc...) and measured voltage , about 12.34v

is this OK???

can someone please with xc90 2016-2019 measure the voltage (car off) after car is locked for one day and give me their voltage.

Love this car, but I want to make sure , the battery is ok?

 

Simple answer is if you can leave your car for days and it starts up, the battery is fine.

The voltage of the battery won't wander unless there's a large current draw where the battery can't keep up (chemically it has some resistance) - you may have some minor resistance with your meter probes or need to zero out your meter to measure the exact voltage but anything within the 12 to 12.6V range sounds normal. If you are concerned about a current drain, you can measure that to see if its in spec. You are correct in noting that there is a standard parasitic draw for powering stuff with the key off but its very small - not sure about your model but on the older Volvos the expected value is somewhere under .02 Amp (20mA). To measure you'd put your multimeter in mA mode and put in series between the battery terminal and cable.