Irish Rail says full train services will operate from first service on Sunday between Greystones and Dalkey.
Services have been disrupted since a fire last week in a signalling relay room at Bray.
But the company says repairs were completed ahead of schedule.
The first service from Bray will be at 9:00am and from Greystones at 9:20am tomorrow morning.
Iarnród Éireann has apologised for any inconvenience this disruption may have caused.