Illinois CDL — Air Brakes practice
Signals & Pavement Markings
How to read traffic signals, lane lines, and pavement markings — including yellow and white lines, arrows, and flashing lights.
Questions reviewed against the official Illinois driver handbook · July 7, 2026
1 questions · pass with 1 correct. You get instant feedback and an explanation after every answer.
Study questions with answers
1 sample Signals & Pavement Markings questions with the correct answer, a short explanation, and the official handbook reference. Read through them, then take the quiz above.
1. What is the function of the stop light switch in an air brake system?
Correct answer: It turns on the brake lights when you apply the brakes
An air-operated electric switch lights the brake lamps whenever the brakes are applied, warning drivers behind you.
Source: Illinois CDL Study Guide — Section 5.1.12: Stop Light Switch
More CDL — Air Brakes topics
Practice Signals & Pavement Markings in another state
Every Illinois question is written from the official Illinois driver handbook and checked against its current edition. DMV Test Free is a free, independent study resource — not affiliated with any DMV or government agency. About DMV Test Free