Intersections: Practice Questions & Explanations

When making a left turn at an intersection, you must yield to oncoming traffic. This is true at uncontrolled intersections, intersections with green lights (when no left-turn arrow is present), and even when you have arrived at the intersection first if you are turning left while another vehicle is going straight. Left turns are one of the most common situations for collisions because the turning driver crosses the path of oncoming traffic; mistakes about gaps, speed of oncoming traffic, or visibility are common. Wait for a gap large enough that you can complete the turn without forcing oncoming traffic to slow down. When in doubt, wait. A clear gap is always available eventually; a rushed turn that causes a crash is not recoverable.

A flashing red light is treated exactly like a stop sign: come to a complete stop at the stop line (or before the intersection), yield to any traffic in or approaching the intersection, then proceed when safe. A flashing yellow light is treated like a yield sign or a caution signal: slow down, proceed with care, and yield to any conflicting traffic. Flashing signals are typically used at intersections where full traffic signals are temporarily disabled, at quiet intersections during overnight hours, or as part of railroad warning systems. Sitting and waiting at a flashing red until it turns green will keep you sitting forever because the signal is operating as designed.

A roundabout is a circular intersection where vehicles travel counter-clockwise around a central island and yield to traffic already in the circle. Roundabouts replace traditional intersections and traffic signals in many places because they have fewer conflict points than four-way intersections, slow traffic to a safer speed (typically 15–25 mph), reduce serious crashes (fewer head-on or T-bone collisions), and keep traffic flowing without waiting for signals. Approach a roundabout in the correct lane (right lane for right turns and continuing, left lane for left turns or U-turns), yield to traffic already in the circle, enter when there is a safe gap, and exit by signaling and moving to the right lane. Pedestrians cross at the entries, not within the circle.

A DARK OR NON-FUNCTIONING TRAFFIC SIGNAL must be treated as a FOUR-WAY STOP in virtually all US states. This is a statutory requirement, not just a recommendation. HOW A FOUR-WAY STOP WORKS: (1) All vehicles must come to a COMPLETE STOP at the stop line or before entering the intersection; (2) The first vehicle to arrive and stop has the right-of-way to proceed first; (3) When two or more vehicles arrive at approximately the same time, the vehicle on the RIGHT has the right-of-way (right-before-left rule); (4) If vehicles are directly opposite and turning in different directions, left-turning vehicle yields to straight-through traffic. WHY DARK SIGNALS ARE TREATED AS 4-WAY STOPS: A dark signal means all approaches have lost their control — none can proceed safely without coordination; treating it as uncontrolled (no one yields to anyone) would create chaos and high-speed conflicts at a potentially blind intersection. COMMON MISTAKE: Some drivers slow significantly but don't stop, treating it as a caution light — this is incorrect and potentially unlawful. A complete stop is required. POLICE DIRECTION: If a law enforcement officer is directing traffic at a dark-signal intersection, always follow the officer's signals, which override traffic device rules.

FLASHING YELLOW LIGHT means CAUTION — proceed but with care. This is different from a solid yellow (which means prepare to stop for an upcoming red) and different from a flashing red (which means stop). FLASHING YELLOW — WHAT IT MEANS: The intersection has reduced control (often used for cross-traffic that has a flashing red); you must: reduce speed; look carefully for crossing vehicles, pedestrians, and cyclists; yield if cross-traffic is present or approaching; proceed when safe — you do NOT need to stop if the way is clear. COMMON LOCATIONS: Flashing yellow is used at intersections where one road is more heavily traveled (the main road gets yellow, the cross-street gets red); at times of day when full signal operation isn't needed (late night flash mode); at intersections with lower traffic where a full signal isn't installed but some control is desired. CONTRAST WITH FLASHING RED: A FLASHING RED means STOP completely, then proceed when safe — it functions identically to a stop sign. Many intersections have one direction with flashing yellow and the cross-direction with flashing red. CHECK YOUR STATE: Most states align with the Manual on Uniform Traffic Control Devices (MUTCD) standard described here, but there may be minor variations in specific local ordinances. ARROW SIGNALS: A flashing YELLOW ARROW (at turn lanes) specifically means you may turn in the indicated direction but must yield to oncoming traffic and pedestrians — it is not a protected turn.

A steady yellow light means the signal is about to turn red and you should prepare to stop. If you can stop safely before the intersection, you should. You should proceed through only if you are already so close that stopping would be unsafe (for example, requiring hard braking that could cause a rear-end collision). The yellow light is a warning to clear or stop for the intersection, not an invitation to accelerate and 'beat the red,' which is dangerous and often illegal. Approaching intersections at a controlled speed and being ready to stop on yellow is safe intersection practice.

A flashing red traffic light means the same thing as a stop sign: come to a complete stop, yield to other traffic and pedestrians as required, and proceed only when it is safe. A flashing yellow light, by contrast, means proceed with caution — slow down and be alert, but you do not have to stop. Flashing signals are often used at night or at intersections where full signal operation is not needed. Treating a flashing red exactly like a stop sign — full stop, then go when clear — is standard intersection knowledge tested on the permit exam.