CDL Air Brake Practice Test Containing
30 Questions and Answers Best Graded
A+ 2024-2025.
The parking or emergency brake on a heavy vehicle can only be held in
position by something that cannot leak away, like:
a. Fluid pressure
b. Spring pressure
c. Air pressure
d. Any of the above - Answer: b. Spring pressure
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, CDL Air Brake Practice Test
A straight truck or bus air brake system should not leak at a rate of more
than __ psi per minute with the engine off and the brake released.
a. 1
b. 2
c. 3
d. 4 - Answer: c. 3
Your vehicle has dual air brake system. If low air pressure warning
comes on for the secondary system or for one system, you should:
a. Bring the vehicle to a safe stop and continue only when the system is
fixed.
b. Reduce your speed, and test the remaining system while under-way.
c. Reduce your speed, and drive to the nearest garage for repairs.
d. Continue at normal speed if only the secondary system fails. -
Answer: a. Bring the vehicle to a safe stop and continue only when the
system is fixed.
If your vehicle has an alcohol evaporator, it is there to:
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