Traffic signals — Pennsylvania Permit Test
Traffic signals on the Pennsylvania permit test — 19 rules, each with the reason behind it and a question on it while it is fresh.
The rules
At a steady red signal you must stop before crossing the marked stop line or crosswalk, and if there are no lines, before entering the intersection. Wait for the green signal before you start.
The line is set back far enough that people crossing have room to walk in front of you.
You may turn right on a red signal unless a no turn on red sign is posted, but you must stop first and check for and yield to people crossing and to other traffic.
The stop is what buys you the look, and a cyclist on your right is easy to miss without it.
You may turn left on a red signal only if you are in the left lane turning from a one-way street onto another one-way street, unless a sign forbids it, and you must stop and yield first.
Both streets running one way is what keeps the turn clear of oncoming traffic.
A steady yellow signal tells you a red signal will soon appear: slow down and prepare to stop, but if you are already in the intersection or cannot stop safely, go through carefully.
Speeding up to beat it puts you in the crossing exactly as the other direction gets its turn.
You may continue carefully through a yellow signal if you are already within the intersection or cannot stop safely before entering it.
Stopping dead inside the crossing is worse than clearing it.
A steady green signal means you may drive through the intersection if the road is clear, and you may turn unless a sign forbids it, but when turning you must yield to vehicles and people already in the intersection.
The signal gives you the crossing, not the space inside it somebody is still walking through.
If a green arrow changes to a steady green signal you may still turn that way, but you must first yield to people crossing and to oncoming traffic.
The arrow held the oncoming traffic for you; the plain signal does not.
A steady green arrow means you may turn the way it points, and the turn is protected because oncoming traffic is being held at a red signal.
Protected means somebody else is holding the oncoming traffic, which a plain signal does not do.
A steady red arrow means you must stop and may not turn the way it points; the same turns allowed on a steady red signal are allowed on a steady red arrow.
The arrow holds your movement alone while everything else keeps going.
A flashing red signal has the same meaning as a stop sign: come to a complete stop, look both ways, and go only after the intersection is clear.
A flashing signal never turns to go, so nothing will tell you when your turn is but your own look.
A flashing yellow signal means slow down, look and go with care.
Nobody is being told to stop, so the intersection only works if everybody slows.
A flashing yellow arrow means you may turn that way, but you must first yield to oncoming traffic and to people crossing, because the turn is not protected.
The oncoming traffic has a green signal, so nothing is holding it for you.
A traffic signal that is not working should be treated as though it were a four-way stop sign.
With nothing telling anybody to go, every driver has to take a turn.
When signals are arranged in a vertical line the red signal is always on top and the green signal on the bottom; arranged horizontally, stop is always on the left.
The order is fixed so a driver who cannot tell colors apart can still read the signal by position.
Some highway entrance ramps have ramp-metering signals that alternate between go and stop; on a single-lane ramp only one car may enter each time it turns to go.
The signal spaces cars out, but it does not clear a gap in the traffic for you.
A ramp-metering green signal does not protect your entrance onto the highway; you must still find a safe gap in traffic.
The signal controls the ramp, not the road you are joining.
A downward green arrow on a lane use control signal means you may use that lane.
These lanes reverse direction by time of day, so the signal is the only thing telling you which way it runs.
A steady yellow cross above a lane means you must change lanes, because the direction of travel for that lane is about to be reversed.
The lane is about to start running at you.
A steady red cross above a lane means you are not allowed to use that lane at all.
The lane is being run the other way, so a car in it is facing oncoming traffic.
On the test
Where must you stop at a steady red signal?
Before the stop line or crosswalk. The line is set back far enough that people crossing have room to walk in front of you.
How this works
Most practice tests hand you a bank of questions and leave the manual somewhere else. This one puts them together.
You read one law and the reason behind it, then answer a question on that law while it is still fresh. Get it right and you move on; get it wrong and you have found the gap while it is cheap to fix, not on the morning of the exam.
Learning one rule at a time, and proving it immediately, is what turns a manual you skimmed into something you actually know — and it makes studying feel like getting somewhere rather than like waiting to find out.
All Pennsylvania permit topics
Where these come from
Every rule here is checked against PA Driver's Manual, published by the Pennsylvania Department of Transportation, and against the state code itself. Last checked 2026-09-06.