Alloy Wheels
Hi....the 'spiders web' sort of corrosion is caused by water ingress under the laquer....sadly caused by something weakening the coating...ie ..stones...or even pressure washing can force water into the laquer....sadly unlikely to be covered by warranty....
Without seeing the wheel I cant make an informed judgment...also I said 'unlikely' it all depends on why the corrosion is there...well done for getting yours under warranty,nice to hear peugeot giving customer satisfaction....