RobotRisk › TTC (Toronto Transit Commission) › 11 Dec 2024
Automatic Train Control server outage shuts down entire Line 1
S2 · 11 Dec 2024 · TTC (Toronto Transit Commission) · Toronto, ON, Canada
Record
| Company | TTC (Toronto Transit Commission) |
| Industry | Other |
| Type(s) | outage |
| Date | 11 Dec 2024 (day precision) |
| Time of day | ~07:00 ET |
| Location | Toronto, ON, Canada · Line 1 |
| Severity | (minor injury or single-unit damage) |
| Scale | Line 1 systemwide, ~30 minutes |
| Confidence | high |
| Verified flag | Cited source on file; not independently re-verified |
Summary
A server running the Automatic Train Control (ATC) signalling system's train-routing function went offline for unknown reasons on the morning of December 11, 2024, triggering the system's failsafe and halting all Line 1 subway service from Vaughan to Finch for about 30 minutes during rush hour; the TTC's interim CEO called the recurrence of such ATC issues "unacceptable."
Primary source
Publisher: CP24 · Retrieved: 2026-09-16
Supporting source rows (1)
| Date | Supporting source row | Publisher | Link |
|---|---|---|---|
| 11 Dec 2024 | Automatic Train Control server outage shuts down entire Line 1 | CP24 | CP24 |
Other context
outage context
TTC (Toronto Transit Commission) industry position
Related incidents
Other TTC (Toronto Transit Commission) entries
- None on file.
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