A Dark Signal Is a Four-Way Stop

We lose power more often than we used to, and for reasons that are specific to this part of the state: wind events, public safety power shutoffs during fire weather, heat waves that stress the grid, and the occasional car into a pole. When it happens on a major arterial at the wrong hour, an intersection that normally handles a signal's worth of traffic suddenly has no instructions at all.

The rule, and it is not ambiguous

Vehicle Code section 21800 covers this directly: when the traffic signal controlling an intersection is inoperative, drivers are to stop and proceed as though the intersection were controlled by stop signs in all directions. A four-way stop. Every approach, every time, first to arrive goes first, and yield to the vehicle on your right when two of you arrive together.

The reason this page exists is that plenty of drivers do not know that rule, or know it and assume the main road keeps priority because it always has. Those two assumptions meeting in the middle of an intersection is the entire failure mode.

Flashing is different from dark

Do not confuse the two, because they mean different things:

• Dark signal — treat it as a four-way stop.
• Flashing red — it is a stop sign for that approach. Stop, then proceed when clear.
• Flashing yellow — proceed with caution. It does not mean go, and it usually means the cross street has a flashing red, which means people are pulling out.

A signal can also be in a partly failed state where one direction has an indication and another does not. If what you are looking at does not make sense, treat it as a four-way stop and go slowly. Nobody has ever been hurt by being the person who stopped.

How to drive one safely

1. Stop fully at the limit line, not the rolling version. Other drivers need to see you stop to know what you are doing.
2. Make eye contact before you move. At a dark intersection this is doing more work than the rules are.
3. Go one at a time, in order. Two cars moving together is where it goes wrong.
4. Watch for the driver who is not stopping. Wait an extra beat before entering, especially on the road that normally has priority.
5. Expect pedestrians who have no walk signal and are making their own judgment about when to cross.

Traffic officers directing traffic override the signals entirely, functioning or not. Follow their directions even when they conflict with a working light.

The rest of the outage

An outage takes more than the signals. Streetlights are gone, which changes the whole visual environment on an arterial you know well — pedestrians, cyclists and lane markings all get much harder to read. Gas stations may not be pumping. And after a wind event there is often debris in the roadway that nobody has cleared yet.

Downed lines are the serious one. Never drive over a downed power line, never assume a line on the ground is dead, and if a line comes down on your vehicle, stay inside and call for help rather than stepping out. That is one of the few pieces of driving advice with no nuance attached to it at all.

The insurance side, briefly

Two things worth knowing. A collision at a dark intersection is an ordinary at-fault analysis: the signal being out does not excuse a driver who failed to stop, and these claims often come down to physical evidence and any nearby camera, because both drivers usually believe they went first. And damage to your parked car from a falling limb or a downed line during the event is generally a comprehensive matter rather than a collision one — which only helps if you carry comprehensive, and it is optional in California.

If you are not sure whether you carry comprehensive, send us the declarations page before the next wind event and we will tell you in plain English.