Flashing Yellow, Flashing Red, and a Signal That Is Completely Dark
At 9:40 p.m. you are westbound on a two-lane state highway posted 55 mph, five miles from the nearest town, with light rain still falling after a thunderstorm knocked out power in the area. You approach a four-way intersection where the signal is running on backup power: your approach shows a single flashing yellow, and across the intersection you can see the cross street's signal flashing red. A pickup is waiting on the cross street, headlights on. Trees on the right limit your view down that road to about 250 feet. A fully loaded grain truck is following you roughly two car lengths back - close enough that you can read its grille in your mirror. About 600 feet past the intersection, a second signalized crossing sits completely dark. Your turnoff is just beyond that second signal, and you are already running late.
1. What does the flashing yellow require of you on approach, and how does the grain truck behind you change how you handle it?
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A flashing yellow is not a green light and it is not a stop. It means proceed with caution: you may not enter until you can do so safely, and you must still yield to any vehicle already lawfully in the intersection and to pedestrians. You do have priority over the driver facing the flashing red - but priority you can only use if you actually get there.
How to handle it:
- Lift off the throttle and cover the brake at least 300 feet out. With a loaded grain truck two car lengths behind, do your slowing early and gently; a late, hard stop from 55 mph is exactly how a rear-end collision with a heavy truck happens.
- Tap the brake pedal two or three times before you really slow, so the truck driver sees brake lights and has time to react.
- Scan the cross street left-right-left. The trees cut your view to 250 feet, which at 55 mph is about three seconds of travel - not enough to assume anything about the cross street, so arrive at a speed from which you can stop.
- Keep your headlights on and your lane position steady. Erratic movement plus a tailgater is a worse combination than either alone.
2. The pickup on the cross street edges forward as if it is about to go. Who has the right-of-way, and what should you actually do?
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Legally, the pickup faces a flashing red, which requires a full stop and a yield to traffic on the through road. You hold the right-of-way. That does not make the conflict safe.
A single flashing red at 9:40 p.m. in rain is a classic situation for a tired or confused driver who reads the signal as 'broken' and rolls through. The trees hide your headlights until you are close, and the driver may be watching the wrong approach.
What to do:
- Enter slowly with your foot over the brake. Do not accelerate to claim the intersection; the goal is to avoid a crash, not to win a rule.
- Watch the pickup's front wheels rather than its headlights. Wheels tell you whether it is genuinely stopping.
- If it creeps into your path, brake in your own lane. Do not swerve left into the oncoming lane or right toward the trees - a controlled stop or a glancing hit is survivable, a head-on or a rollover usually is not.
- Do not flash your high beams to wave the pickup through. Mixed signals cause more crashes at dark intersections than they prevent. If it does enter, let it clear, then proceed.
3. You reach the second intersection and every signal head is dark. Describe your approach, who goes first if two vehicles arrive together, and what you should not assume.
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A signal showing no indications in any direction is treated as an all-way stop. The logic is simple: with no lights, no approach has priority, so the lawful default is that every driver stops and takes turns.
How to handle it:
- Stop at the stop line or crosswalk, or before entering the intersection if neither is marked.
- Yield to any vehicle that arrived before you. If you arrive at the same moment as another vehicle, yield to the one on your right, then proceed one at a time.
- Do not assume cross traffic is stopping merely because the law requires it. Scan each direction twice before you move, and be ready to stop again if someone blows through.
- Signal your turn early, keep headlights on, and once you are safely through, report the outage to the non-emergency line or 911. Two dead signals 600 feet apart is strong evidence the whole corridor is down, which means the next driver behind you faces the same trap.
The temptation at 10 p.m. is to roll through a dark signal because nothing appears to be coming. That assumption is the crash.