The wiring error was not detected by Metro Trains Melbourne’s verification program.
Safety action taken by Metro Trains Melbourne will mitigate the risk of future wiring errors with respect to this modification.
The low-note whistle wiring document has been updated to provide further clarity and to prevent future wiring errors with respect to this modification. In addition, maintainers involved in low-note whistle modification work have been briefed and re-trained on the modification method statements. Further, completed modification work will require self-checks and supervisor checks.
