Services have been disrupted since a fire last week
Iarnród Éireann has confirmed full services will operate between Dalkey and Greystones on Sunday.
Trains will run from the first service, following disruption caused by a fire last week.
Irish Rail say repairs were completed ahead of schedule.
Services were disrupted last week due to signalling damage caused by a firee in the signalling relay room at Bray.
The first service from Bray will be at 9:00am, and from Greystones at 9:20am, on Sunday morning.
All services after that in both directions will operate as per its Sunday timetable.
The company has apologised for any inconvenience caused.