Air Brake Coach
Spring brakesQuestion 19 of 116

The park control valve does not pop out when air pressure is gone. What must you do?

  1. Drive to the next stop
  2. Cage the park springs
  3. Put the vehicle out of service
  4. Use only the trailer brakes
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Correct answer: Put the vehicle out of service

The park control must go back to the park position when air pressure is gone. If it does not, the vehicle is out of service.

Source: Air Brake Manual: A Guide for Instructors (Government of Alberta, Alberta Transportation, March/April 2012), Module 5: Park circuit, page 57

Practice spring brakes

Questions last reviewed: 18 October 2026