CDL Air Brakes Practice Test Results

Question 1
50% answer correctly
Modulating control valves are used to:
Switch between spring and air brakes
Apply the spring brakes gradually
Apply the air brakes gradually
Apply the spring and air brakes together
Question 2
76% answer correctly
For air brakes, the cut-out level is:
The minimum air pressure for the air storage tanks
The level at which the air compressor will start pumping air into the air storage tanks
The level at which the air compressor will stop pumping air into the air storage tanks
The average air pressure maintained in the air storage tanks
Question 3
43% answer correctly
For vehicles that use air brakes, emergency and parking brakes:
Must be a combination of mechanical and air brakes
Can only be air brakes
Must be mechanical brakes
Are not required