KiwiRail is to spend $90 million on new signaling and train control systems for Auckland's rail network.
The company says the upgrade is needed to support the proposed electrification project and an increase in the number of commuter services.
KiwiRail chief executive Jim Quinn says large parts of the Auckland network are old, fragile and prone to failure.
New equipment will include a back-up computer to keep signals working if a failure occurs and a protection system which will automatically intervene if a train passes through a stop signal.
Mr Quinn says key routes between Otahuhu and Britomart, Newmarket and Morningside will be the first to be upgraded.
The equipment will be installed over the next two years.
