Traffic Signals and Pavement Markings
Traffic signals and pavement markings divide space and time on the road. The exam tests signal meanings in unusual states, especially flashing and arrow displays, and whether you can read lane lines correctly.
Signal states
- Solid red: stop at the stop line. Right turn on red after a full stop unless posted otherwise; left on red in Idaho only from one-way to one-way.
- Solid yellow: the light is about to turn red; stop if you can do so safely, otherwise clear the intersection.
- Solid green: proceed if clear; green does not override pedestrians in a crosswalk.
- Flashing red: stop, then proceed when safe, the same duty as a stop sign.
- Flashing yellow: caution; slow and proceed when safe.
- Flashing yellow arrow: unprotected left turn; yield to oncoming traffic and pedestrians. It is not a protected green arrow.
- Green arrow: protected movement in the direction of the arrow.
Pavement markings
- Yellow lines separate traffic moving in opposite directions: solid means no passing, dashed means passing permitted when safe, double solid means no passing either way.
- White lines separate lanes moving the same direction; a solid white edge line marks the right edge.
- Stop bars, crosswalks, and railroad markings tell you where to stop and where pedestrians or trains have priority.
- A diamond symbol marks an HOV lane; sharrows mark a shared bicycle lane.
Worked example
You are waiting to turn left and the left arrow changes from green to flashing yellow. You may still turn, but you must yield to oncoming traffic. A flashing yellow arrow is permission to proceed with caution, not a protected turn.
Traps
Treating a flashing yellow arrow as a green arrow; stopping on a flashing yellow when the intersection is clear; crossing a solid yellow line to pass; assuming a green light means pedestrians must wait.