"Signalfeil" (signal error) does not actually always mean that there is an error with the signaling! Happened to read up on this while stuck on a train due to signal error!

It is means that they have gotten a signal that there is an error somewhere, which might be the signaling system, but also loads of other things! [1]

The term is super confusing thought, should probably have been "error signal" instead

[1] https://www.banenor.no/nyheter-og-aktuelt/bane-nor-forklarer...