Japan Ordinary Licence Theory key terms

A legally defined slow speed at which the vehicle can stop immediately if necessary, generally interpreted as roughly 10 km/h or less. Required at blind intersections, when turning at such intersections, and near stopped trams.

Bringing the vehicle to a complete halt and confirming safety before proceeding. Mandatory at stop signs, at stop lines, and at railway crossings; a rolling stop is a violation.

A white transverse line painted across the lane that marks where a vehicle must halt for a stop sign, signal, or crossing. The front of the vehicle must not pass it while stopped.

An intersection where buildings, walls, or hedges block the view of crossing traffic. Approaching vehicles must slow down (徐行) and, if a stop line or sign exists, stop before entering.

A road designated as having priority at an intersection, usually wider or marked by signs and centre lines. Traffic on the narrower or non-priority road must yield to vehicles on the priority road.

An electrically operated device with red, yellow, and green lights controlling traffic. Red means stop before the stop line; yellow means stop unless stopping is unsafe; green means proceed after checking safety.

A yellow light warns that the signal is changing to red. Drivers must stop before the stop line unless doing so would be dangerous, for example when a following vehicle is close behind.

Signs erected along roads that instruct, warn, or guide drivers. They are classified as warning signs (yellow diamonds), regulatory signs (blue or red circles), and guide signs (rectangles).

Markings painted on the road surface, such as centre lines, lane lines, stop lines, and zebra crossings. They have the same legal force as roadside signs and must be obeyed.

The obligation to signal with the direction indicator at least three seconds before changing lanes, turning, or pulling away from the kerb, and to confirm the mirror and blind spot first.

Moving from one lane to another. The driver must signal, check mirrors and blind spots, and yield to vehicles already in the target lane; abrupt or signal-free changes cause sideswipe crashes.

The habit of checking mirrors, blind spots, and surrounding traffic before any manoeuvre. Direct visual checks, not mirrors alone, are required where the view is obstructed.

The difference in turning radius between the front inner wheel and the rear inner wheel. The rear wheels cut inside the front wheels' path, so large vehicles can crush cyclists or pedestrians at corners.

A crash in which a turning vehicle sweeps a bicycle or pedestrian into its path, typically caused by the rear inner wheel cutting the corner. Prevention requires mirror checks and shoulder checks before turning.

A collision between two vehicles entering the same intersection from crossing directions. Most common at blind intersections and often caused by failure to slow down or stop.

The gap to the vehicle ahead. It must allow stopping if that vehicle brakes suddenly; a common rule is at least the distance covered in two seconds at the current speed.

A rear-end collision in which a following vehicle hits the vehicle ahead. It is usually blamed on insufficient following distance or on the follower failing to watch the road.

Aggressive driving such as tailgating, horn blasts, or cutting in to force another driver to yield. It is punishable by law and is a major trigger of road-rage incidents.

A place where a road crosses railway tracks. Drivers must stop before the stop line, look and listen both ways, and never enter while the barrier is down or a train is approaching.

A collision between a road vehicle and a train at a level crossing. Causes include entering while the warning sounds, stalling on the tracks, and ignoring barriers.

A braking technique in which the pedal is pressed lightly first to show brake lights and warn followers, then pressed harder to stop. It reduces rear-end collisions.

Slowing the vehicle by releasing the accelerator with the transmission in gear, so the engine resists the wheels. It supplements the foot brake on long descents and prevents brake fade.

Loss of braking power caused by overheating of the brake pads and discs after repeated or prolonged use, as on long downhill runs. Engine braking and lower gears prevent it.

Sudden hard braking that risks a rear-end collision and loss of control. It is permitted only to avoid imminent danger; normal slowing should start early and gently.

The pressure of air inside a tyre. Too low increases rolling resistance and heat and worsens fuel economy; too high reduces grip. It should be checked when the tyres are cold.

The pre-drive check of tyres, brakes, lights, fluids, and mirrors that the driver must perform. It is legally required before driving and prevents breakdowns and accidents.

Fuel-efficient, environmentally friendly driving: gentle acceleration, early accelerator release, steady speed, and avoiding unnecessary idling. It cuts emissions and fuel cost without slowing journeys.

Switching off the engine while stationary, for example at long waits or level crossings. It saves fuel and reduces exhaust emissions and noise.

Avoiding hard starts and rapid acceleration, which sharply raise fuel consumption and emissions. Smooth acceleration to cruising speed is a core element of economical driving.

The legal duty of a driver involved in a crash to stop immediately, help the injured, and report to police. Leaving the scene is a serious offence (ひき逃げ).

The legal obligation to give first aid to anyone injured in a crash, such as stopping bleeding and calling an ambulance, before attending to other matters.

Fleeing the scene of a crash without stopping, helping the injured, or reporting to police. It carries heavier penalties than an ordinary accident.

First aid given at the scene before medical help arrives, including checking breathing, stopping bleeding, and keeping the casualty warm and still.

Drivers must carry a valid driving licence while driving and produce it when asked by police. Driving without carrying it is an administrative violation.

The periodic renewal of a driving licence, generally every five years for ordinary drivers, with shorter periods for those with violations. Renewal requires a lecture and eye test.

The green-and-yellow mark that drivers with less than one year of experience must display on the front and rear of the vehicle. Failure to display it is a violation.

Driving with alcohol in the breath above the legal limit, even if the driver does not feel drunk. It is punished with licence points, fines, and possible imprisonment.

The administrative revocation of a driving licence for serious violations such as drunk driving or hit-and-run. The driver loses the right to drive and may face a disqualification period.

Driving while too tired or sleep-deprived to stay alert. It is prohibited and is a leading cause of highway crashes; rest breaks are required on long trips.