When is it appropriate to use cruise control?

• A. On dry, open surfaces with steady traffic and no heavy braking or acceleration.
• B. In heavy traffic to maintain speed.
• C. On dry, open surfaces with steady traffic and no heavy braking or acceleration; avoid use in rain, snow, or heavy traffic.
• D. On hills with frequent braking.

Answer: (C)

Cruise control works best when you can maintain a constant speed without needing to slow down or speed up suddenly. That’s most reliable on dry, open roads where traffic is steady and you’re not braking or accelerating heavily. In these conditions the system can hold a steady pace smoothly, reducing driver effort. It should be avoided when rain or snow threatens traction, or when traffic is heavy and speeds change often, because the system can’t respond quickly enough to unpredictable conditions. Hills with frequent braking are also unsafe for cruise control, since the system may not manage speed safely on inclines. So the guidance is to use cruise control only on dry, open surfaces with steady traffic and no heavy braking or acceleration, and to avoid it in rain, snow, or heavy traffic.