Did this error pop up before you changed the battery?

If it did, it doesn't necessarily mean the battery is dead, and replacing it wouldn't get rid of it.

It could be the DC-DC converter that charges the 12V battery (the equivalent of the alternator so to speak) that has failed for instance.

I had the 12V go flat ~4 years ago and I recall the volvo engineer after jump starting it had this error and couldn't get rid of it for a while and was on a call with Polestar, I think it went away in the end because the battery charged beyond some threshold.

If you have a multi meter handy I'd check the voltage across the battery to see if it's reasonably high, and if you try to activate the car you should see it raise to >14V when the propulsion battery goes online.

 

That error popped up before the battery was changed, but the mechanic that worked on the car, confirmed that the battery was no good. This is great information, thank you so much! I'm actually ending up getting it towed over to Volvo now, fingers crossed. 🤞

 

Did you try clearing error codes with an OBD scanner after replacing the battery?

 

No, I really didn’t know what to do after trying to swap out the 12v battery. I found this forum way after it all was said and done 😅. I took it to Volvo, who informed me yesterday that there’s an issue with the larger battery.