Southern Line train services in Auckland have been disrupted for a second time this morning, with some services now switching to the Eastern Line.
Earlier, all Southern Line train services were suspended after the vehicle hit a train overbridge in Ellerslie.
Auckland Transport said bus services were being brought in to replace the trains as a result.
At 7am Auckland Transport said that trains on those lines would be down "until further notice''.
A short time later it announced engineers had cleared the bridge and trains on the Southern Line would resume normal services.
Since then it has announced that "due to a train crew matter" normal services have been suspended again and Southern Line services will travel via the Eastern Line, not stopping between Ōtāhuhu and Britomart.
Customers between Ōtāhuhu and Britomart are asked to use the bus services.
Motorists on the Northern motorway also faced delays after a crash on the Northcote Road citybound on-ramp.
The vehicle has since been towed away.