Arkansas Commercial Driver License (CDL) Practice Test

When are you required to dim your lights?

1. When following a vehicle within 500 feet

2. When parked on the side of the road

3. When driving through a tunnel

4. When driving below 55 mph

The correct answer is: When following a vehicle within 500 feet

Dimming your headlights is required when following a vehicle within 500 feet. This practice helps to prevent glare that can impair the vision of the driver in front of you. By dimming your lights in this situation, you are being considerate and ensuring safety on the road. It reduces the likelihood of causing distraction or discomfort to other drivers, which can help prevent accidents. The other situations offered aren't universally applicable for dimming your lights. For instance, while parked on the side of the road, turning on your parking lights or hazard lights is more relevant than dimming your headlights. In tunnels, there are often specific lighting systems, and while good driving practices may suggest adjusting your lights according to conditions, it’s not a strict rule like the 500-foot following distance. Lastly, speed does not dictate the use of high beams in the same manner as being too close to another vehicle does; the focus should be on the distance to other road users, not just speed alone.