He said they went into the Cook Strait to investigate the issues, before deciding to return back to Wellington.
Nalder confirmed there was no risk to anyone on board, and things are going smoothly as they return now.
Interislander executive general manager Duncan Roy said the vessel is returning to Wellington so the technical issue could be investigated and resolved by technical staff based there.
“The issue became apparent as part of standard procedures prior to entering Tory Channel, and the return to Wellington was decided on as a safety precaution rather than sailing through the Sounds.
“The appropriate authorities have been notified, and we will work with our passengers and freight customers to reschedule them,” Roy said.
Sign up to The Daily H, a free newsletter curated by our editors and delivered straight to your inbox every weekday.