Taichung's driverless green line metro has broken down seven times in under eight months, and city councillors are now openly questioning whether the system is safe.

• Most of the recent failures trace back to the signalling system, with platform door and control faults, power trips and train breakdowns also hitting the line since late last year.
• One stretch in June saw two separate failures inside 48 hours.
• An audit found high-risk emergency repair jobs are rising as a share of callouts, and the average repair now takes far longer than it did a year ago — a sign the faults are getting harder to fix.
• Breakdowns cluster at rush hour, when trains run closest together and delays hurt most.
• Passengers are left without clear information during outages, unsure whether to get off or how to continue their journey.

Outlook: The metro operator has brought the original equipment maker back in to inspect the system and restart the project, but councillors want a concrete fix plan before the next failure.