u/Goran-II

Can someone tell me what could have caused this damage to my serpentine belt?

The damage is on the outer side of the belt — the ribs still look like new all the way around. The damage is localized to the area shown in the photo: a rip in the middle of the belt, damage immediately beside it, and edge damage farther down the belt on the opposite side (in the direction of rotation).

I’ve checked all the pulleys and they all seem fine. Both the belt (Continental) and the tensioner (INA) were installed about a year ago.