Commenting on the incident, a spokesperson for P&O Ferries said: "Following a temporary mechanical issue, the European Causeway is now continuing on its scheduled journey to the Port of Larne under its own propulsion, with local tugs on standby, where it will discharge its passengers and cargo as planned.
"There are no reported injuries on aboard and all the relevant authorities have been informed.
"Once in dock a full independent investigation will be undertaken."
A statement from Larne RNLI added: "Three RNLI lifeboats were requested to launch this afternoon to assist a passenger ferry in difficulty one mile south east of The Maidens.
"Larne RNLI’s all-weather lifeboat launched at 2.17pm while Red Bay’s RNLI’s all-weather lifeboat launched at 2.35pm followed by the inshore lifeboat at 3pm.
"The ferry is now tied up in Larne port and all lifeboats have been stood down."