South Carolina Driver's Permit Practice Exam

When should tire pressure be checked?

1. After a long drive

2. When tires are warm

3. When tires are cold

4. Only when the warning light illuminates

The correct answer is: When tires are cold

Tire pressure should be checked when the tires are cold because this provides the most accurate reading. When tires are cold, the air inside them has not been heated by friction from driving, which can cause the air to expand and give a false reading of higher pressure. Checking tire pressure under these conditions ensures that you have an accurate measurement, helping to maintain proper tire inflation, improve fuel efficiency, and enhance overall vehicle safety. Checking tire pressure after a long drive or when the tires are warm is not ideal because the heat generated from driving can increase the air pressure inside the tire, misleading you about the actual pressure. Relying solely on a warning light for checking tire pressure is also not sufficient, as it may not alert you until the tire pressure is already critically low, which could pose safety risks. Regularly checking tire pressure when the tires are cold is an important part of vehicle maintenance.