The governor cuts out (stops the compressor from pumping) at approximately 125 PSI. This prevents over-pressurization of the system during normal operation while maintaining adequate braking pressure.
The CDL (Commercial Driver License) exam tests your knowledge of commercial driving rules, safety procedures, and vehicle operation. You must score 80% or higher to pass the written knowledge test. The exam covers general knowledge, air brakes, combination vehicles, and various endorsements.
This question is from the CDL Air Brakes Test #1 section. Practice with more questions from this category to build confidence before taking the official DMV test.
Browse All Free CDL Practice Tests →