Illinois CDL Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

The service brake is the primary braking system utilized during normal driving situations. It is designed for regular stopping and slowing down of the vehicle under typical driving conditions. This system is activated by the driver’s foot through the brake pedal, allowing for controlled and effective deceleration when needed.

Other options, such as the parking brake, are generally used to secure the vehicle when it is stationary, preventing it from rolling. The emergency brake is intended for use in situations where the service brake fails, providing a backup means to stop the vehicle. As for the brake control brake, this term is less commonly used and may refer to a system that manages braking in certain conditions but does not represent a standard braking system for regular driving. Hence, the service brake is the correct answer contextually, as it is specifically designed for everyday operation of the vehicle.