Diagnosing an xperia 10 ii with blinking led issue: is it the battery?

Here's a short video from a recent operation on a Xperia 10 ii with 'blinking led' issue, not booting.
Following some tickets online it's the battery, but there's a normal voltage...
Thanks for watching this video!
// Subscribe //
Channel subscriptions are here with some exclusive video, community post and original pictures:
/ @jolladevices