Traffic signals can go out for a variety of reasons. These outages can range from short glitches to full signal blackouts. The most common causes include:
Power outages due to storms or grid failure
Vehicle crashes damaging signal cabinets or poles
Construction work disrupting underground cabling
Hardware failure in the controller or signal head
Software bugs in the signal programming system
What to Do at a Blacked-Out Intersection
If you approach an intersection and all signal lights are completely off, treat it as a four-way stop.
Rules to follow:
Come to a complete stop at the stop line.
Yield to the vehicle that arrived first.
If two vehicles arrive at the same time, yield to the driver on your right.
Always yield to pedestrians in the crosswalk.
Tip: Treating the intersection with caution reduces the risk of crashes during unexpected outages.
⚠️ What Flashing Lights Mean
Sometimes the signal doesn’t go dark—it switches to a flashing mode. This happens when the system enters fail-safe mode during a malfunction or power dip.
Flashing Red Light 🚨
Means STOP completely.
Treated exactly like a stop sign.
Yield based on right-of-way rules.
Flashing Yellow Light ⚠️
Means PROCEED WITH CAUTION.
Cross the intersection only when it’s safe to do so.
Yield to pedestrians and any traffic already in the intersection.
What Happens Behind the Scenes
When a signal outage occurs, local traffic maintenance crews or DOT teams are alerted in one of several ways:
Automated alerts from the signal controller
Citizen reports via non-emergency numbers
Real-time monitoring from city traffic operation centers
Technicians are dispatched to:
Inspect the controller and wiring
Reboot or reprogram the system
Coordinate with utility providers if power is involved
Set up temporary signage or deploy officers if needed
Emergency Response and Law Enforcement
In major or high-traffic intersections, police officers may be deployed to manually direct traffic while signals are being repaired. This helps:
Prevent backups during rush hour
Reduce the chance of driver confusion or collisions
Ensure safe pedestrian movement
âś… How You Can Help
If you notice a traffic signal outage, you can:
Report it to your city’s public works or transportation department
Avoid the area if traffic is backing up
Stay alert and patient—outages are temporary, but safety is permanent
.gif)