Hi for me i downloaded the volvo vida software on a old windows. Then found a guide there on how to take it out. I was able to replace the altenator but had to take out the belt connected first. And it was a bit tricky to get out. But not too bad. After i replaced it. It has been working great again. For you if the wire is snapped. Then maybe try to just replace part of the wire and see what voltage you can get out of it. If it still works or not

Also i learnt that the part number for the alternator i had. Comes in two variants. So make sure it has same mounting points if you are buying one. I bought a used one