I recently changed the battery of my iPad 4 A1458 with a third-party one, so I restored it and now I can't pass the activating step, it gives me an activation error. I tried activating it with iTunes but still the same result.
If you’re getting a restore error, here is a starting place.
If the restore succeeds but the device doesn’t finish setup, contact Apple Support as you may need further repair.
It’s unlikely they will service it, but you might have an exemption in some regions.