Pre-trip Inspection Procedures Flashcards
6 cards from real Air Brake Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Pre-trip Inspection Procedures flashcards as text
What should you observe when pumping the brakes with the engine off during a pre-trip inspection?
Answer: Air pressure should decrease gradually with each application, and the low-pressure warning should activate before pressure falls below 60 psi
Each brake application uses air, so pressure drops gradually; the driver verifies the warning light/buzzer activates before pressure falls below 60 psi — confirming the warning system works.
What should a driver inspect at the brake chambers during a visual pre-trip walk-around?
Answer: Chamber condition for cracks or dents, pushrod position and length, dust plugs, and no signs of moisture or oil leaks
Brake chambers must be visually inspected for physical damage, proper pushrod length and condition, and signs of moisture or oil contamination that could indicate internal or external leaks.
How do you confirm proper air line connection integrity at the glad hands during a pre-trip combination vehicle inspection?
Answer: Visually inspect connections for proper coupling and listen/feel for air leaks; confirm colored coupling matches (blue=service, red=emergency)
Glad hands must be visually confirmed as fully coupled, color-coded correctly (blue service, red emergency/supply), and inspected for leaks by feel and sound.
What does it mean if you hear a steady hissing sound from under the vehicle after completing the pre-trip air charge?
Answer: There is an air leak in the brake lines, fittings, or chambers that must be identified and repaired before driving
A steady hissing sound after the system is fully charged indicates a continuous air leak somewhere in the system, which is not normal and must be repaired.
Why is it important to test air pressure buildup time (from 50 to 90 psi) during the pre-trip inspection?
Answer: To verify the compressor is working properly and can maintain system pressure under operating conditions
Testing buildup time confirms the compressor can generate adequate air quickly enough; if it takes too long, the compressor may fail to maintain pressure during driving, risking brake loss.
During the pre-trip, what check verifies that the relay valves and service brake lines to the trailer are functioning?
Answer: Apply the trailer hand valve and listen and feel at the trailer brake chambers for air application and release
Applying the trailer hand valve and physically confirming air flows to and releases from trailer brake chambers verifies the relay valves and trailer brake circuit are functional.