Trains drivers have been given a rark up about not assuming they are on the right tracks following a botch up on the Auckland commuter network four years ago.
The Transport Accident Investigation Commission has released its findings into an incident in south Auckland in 2012.
A controller's mistake meant a commuter train took the wrong tracks at the Wiri junction.
The driver didn't notice his train had taken the wrong tracks and was heading to Papakura instead of Manukau.
He was travelling at just 40km/h, no other trains were about and there was no serious danger.
However, a problem emerged when the driver, following miscommunication with the controller, tried to head back to get on the correct track but was in the path of a following train. They stopped 800m apart.
The TAIC report made no recommendations but said drivers must actively look at, correctly interpret and respond to all signals "rather than making assumptions about what lies ahead of their trains".
Controllers and drivers must also communicate clearly and concisely -- leaving no doubt as to what was going to happen next -- when resolving abnormal situations, it said.