In a statement on Tuesday morning, a Sydney Trains spokeswoman said the IT disruption has been fixed.
«A technical issue which affected some IT systems at Sydney Trains late last night and early this morning has now been resolved,» she said.
«The outage caused temporary disruption to real-time apps and customer display screens at stations.
«IT systems critical to the safe operation of trains were not affected and frequent services continued to operate across the network.»
While the IT disruption and crash were not related, the signal equipment damage is expected to cause delays on the airport line until Thursday.
«Sydney Trains is planning to provide a full service this morning, however, due to signal equipment damage at Riverwood, customers on the T8 Airport & South Line may experience some minor delays,» the spokeswoman said on Tuesday.
The spokeswoman said early investigations found the IT issue was related to hardware, not software, but a full investigation into the problem was under way.