Manitoba Airbrake Practice Exam 2025 – 400 Free Practice Questions to Pass the Exam

The function of the stop light switch in an air brake system is to activate the brake lights when the brake pedal is pressed. This is an essential safety feature that alerts other drivers on the road that the vehicle is slowing down or stopping. When the brake pedal is engaged, the stop light switch closes the electrical circuit, turning on the brake lights. This visibility is crucial in preventing rear-end collisions and ensuring overall road safety, as it communicates the vehicle's actions to others.

Other options pertain to different systems or functions within a vehicle. For example, controlling the temperature of the brake fluid or monitoring brake wear and tear relates to maintenance and performance aspects, but these do not relate to the immediate action of signaling through brake lights. Similarly, signaling for the release of the handbrake involves different mechanisms entirely separate from the stop light switch's role. Overall, the stop light switch's primary purpose is to enhance safety by informing other road users of the vehicle's braking status.