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My sister gave me her old apple watch series 0 (original). I tried charging it and it starts boot looping instantly. I just get the apple logo, it disappears, apple logo, disappears, you get the point. It also stops as soon as i take it off the charger. I think it needs a new battery but i just want confirmation.
Hi Most of the time a boot loop on the charger is a bad battery,due to its age it is most likely the battery as well as battery’s don’t last forever It could be a board level issue but they are very unlikely on Apple Watches Here’s the guide you will need to replace your battery Apple Watch Battery Replacement Hopefully this helps Any questions please ask Thanks:-)