Wellington train passengers face disruptions on Monday, with KiwiRail saying half the usual number of trains will be running during peak times.
A vital rail track evaluation car which checks tracks has broken down meaning required safety checks can't be carried out in the Capital.
As a result all trains on Wellington's rail network have to travel at reduced speeds which is having a big impact on timetables.
The Wellington Regional Council has called it "a monumental failure" and Kiwirail will have to front up to Transport Minister Michael Wood.
KiwiRail's executive general manager for operations, Paul Ashton, spoke to Ingrid Hipkiss.
