Before passing, make sure the passing lane is clear and activate the proper turn signal to show you are going to change lanes. Signal early enough for other drivers to know your plans in advance.

Any defect that may affect the safe operation of a vehicle should be corrected as soon as possible. Defects should be corrected before the vehicle is driven.

If you are under age 21, Pennsylvania's laws do not permit you to drive with any measurable alcohol in your system. If you are under 21, you are considered to be driving under the influence if your blood alcohol level is 0.02 percent or greater.

If you must park on the roadway, use your four-way flashers and allow enough space for passing vehicles. Make sure your vehicle can be seen for at least 500 feet in both directions.

When driving near a blind pedestrian who is carrying a white cane or walking with a guide dog, you must slow down, yield the right-of-way, and then proceed with caution. Be prepared to stop your vehicle in order to prevent injury or danger to the pedestrian.

Unless a posted sign prohibits it, you may turn right or left at a steady green light. When turning, you must yield to other vehicles and pedestrians within the intersection.

This sign is placed at the beginning of one-way streets and ramps to indicate that you must not continue driving in your current direction.

A steady yellow traffic light indicates that the light will soon change to red. You should be prepared to stop for the red light, if it is safe to do so.

If your vehicle breaks down on the highway, you should signal before carefully exiting the roadway and turning on your hazard flashers. Get as far off the road as possible and park in a location where other drivers can easily see you. Lift your hood to let other drivers know your vehicle is disabled.

When approaching a railroad crossing, you must stop your vehicle no closer than 15 feet from the nearest rail if an installed electric or mechanical signal is giving warning of an approaching train. Be aware of other warning signs that may indicate an oncoming train, including seeing a lowered crossing gate or hearing an oncoming train.

In rural areas, an orange triangle is displayed on the back of farm tractors and horse-drawn vehicles designed to operate at speeds of 25 mph or less.

Teenagers who get less than eight hours of sleep per night are at an increased risk of crashing their vehicles when driving.

Because large trucks must make wide turns, it may initially look like a truck is turning left when it is actually turning right. This makes it dangerous to try to pass a turning truck. Truck drivers cannot see vehicles that try to squeeze between them and the curb.

If another vehicle is approaching you head-on in your lane, you should first honk your horn to attract attention. If the other driver does not move over, try to escape to the right. If you swerve left and the other driver corrects at the last instant, you will still crash. If a collision is unavoidable, brake firmly and steadily. Every mile per hour you slow down will reduce the impact.

A steady yellow light indicates that a steady red light will soon appear. If you are driving toward an intersection and a yellow light appears, slow down and prepare to stop. If you are already within the intersection or cannot stop safely before entering the intersection, continue through carefully.

If an emergency vehicle using its lights or siren approaches while you are driving on a one-way street, you must drive toward the nearest roadside and stop.

A speed limit sign shows the maximum legal driving speed for the stretch of highway where it is posted. Driving safely may require you to travel more slowly than the posted limit. When conditions are less than ideal, drivers should slow down.

If you hear a siren or an air horn close by but do not know exactly where the emergency vehicle is, safely pull over to the right side of the road and stop until you are sure it is not headed toward you.