What happens when the TU1 fails?

When the TU1 fails, the emergency brake will apply to the entire length of the train. This safety mechanism is designed to ensure that in the event of a failure in one component (such as the TU1), the system prioritizes the safety of passengers and crew by engaging an emergency braking response.

The design of the train's braking system is such that failure in critical components triggers a comprehensive safety procedure, consequently applying brakes across the entire train rather than affecting only a specific section or allowing continued operation. This ensures that the train comes to a safe stop, minimizing the risk of accidents and ensuring the safety of all onboard.

Other potential options, such as the train stopping immediately or only engaging the brakes on the front car, do not align with the standard safety protocols implemented in such systems. These protocols are in place specifically to avoid partial responses that could lead to unsafe conditions.