The Four-Way Stop With a Broken Signal
You are driving south on a two-lane road at about 30 mph and approach a four-way intersection. The traffic signal is completely dark - no lights showing in any direction. There are no stop signs for your direction, and you see no police officer directing traffic. A car is already stopped in the northbound lane across from you, its left turn signal blinking. A second car approaches from the east on your right and is slowing. A third car is close behind you. You intend to continue straight south.
1. What must you do first as you enter this intersection, and why?
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A dark signal is treated as a four-way stop. You must come to a complete stop at the intersection (at the stop line if there is one, otherwise before entering the crosswalk or intersection), because the signal is not functioning and there is no officer or sign controlling you.
You cannot simply roll through because your light is 'green in your mind' - with no power, every approach is uncontrolled by signal, so the default all-way-stop rule applies. Stopping also gives you time to read the other three vehicles' intentions before committing.
2. Assuming all vehicles arrive and stop at roughly the same time, who goes first, and when is it your turn?
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At a four-way stop, the first vehicle to stop is the first to proceed. If arrivals are simultaneous, yield to the vehicle on your right.
Here the northbound car across from you is already stopped, so it has priority over you. However, it is signaling a left turn, which means it will cross your path. The car from the east is on your right; if it stopped at the same time as you, you must yield to it as well.
So your sequence is: let the northbound left-turner clear (it may also have to yield to the eastbound car depending on timing), then yield to the eastbound vehicle if it is on your right and stopped simultaneously, then proceed straight when the intersection is clear. Do not assume the left-turner will wave you through - proceed only when you can see the path is actually clear.
3. What should you do about the car close behind you, and what does that change?
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The tailgater raises your risk of being rear-ended when you brake for the stop. You should still stop - the law requires it - but brake early and smoothly rather than late and hard, and flash your brake lights early so the driver behind has maximum warning.
What it does not change: you cannot skip the stop or roll through to 'keep traffic flowing' for the follower's benefit. The correct adjustment is gentler deceleration and more following-distance awareness, not a violation. After stopping, if the tailgater is still close, accelerate normally and let them pass rather than speeding up to create a gap.