In Partnership with Thomas Crane Public Library

View instructions
The air brakes endorsement applies to applicants who wish to drive a vehicle with air brakes in Class A, B, or C CDL. To drive a vehicle with air brakes, you must pass the air brake component of the Massachusetts CDL knowledge test. The MA CDL air brakes test consists of 25 questions, and you'll need at least 20 correct answers to pass (80%). The test covers the information found in the air brakes section of the Massachusetts CDL Manual. Take this MA CDL practice test now to prepare for the actual air brakes test!
1. You are driving a vehicle with air brakes when the low air pressure warning light and buzzer come on. You should:
activate your hazard lights and drive to the nearest place where you can stop.
slow down and test your brakes.
pull off the road and stop immediately.
apply the brakes as hard as you can.
2. When the air pressure is built up to governor cutoff, the air leakage rate for combination vehicles with the engine off and the foot brake fully applied should be less than_____ in one minute.
5 psi
2 psi
4 psi
3 psi
3. In vehicles with air brakes, the two markings on a front brake limiting valve are:
high and low.
left and right.
normal and slippery.
wet and dry.
4. By pushing the trailer air supply control knob in, you:
shut the air off and put on the trailer emergency brakes.
supply the tires with air.
supply the trailer with air.
keeps air in the tractor or truck brake system.
5. Spring brakes are usually held back by:
the antilock braking system.
air pressure.
modulating control valves.
the brake pedal.
6. If an aggressive driver is involved in an accident down the road, you should:
stop a safe distance from the accident scene, wait for the police and report the behavior you witnessed.
confront the aggressive driver.
make eye contact with the driver.
try to get their vehicle to the side of the road.
7. The __________ keeps air from going out if the air compressor develops a leak.
tractor protection valve
one-way check valve
air compressor drive belt
emergency relay valve
8. The use of brakes on a steep downgrade is:
dangerous, and should be avoided at all costs.
much more effective than the engine braking effect.
the main braking factor.
a supplement to the braking effect of the engine.
9. If you must drive slowly, how should you alert following drivers?
Flash your brake lights
Use your emergency flashers if it is legal
Help them out by signaling when it is safe to pass
Turn on your taillights
10. Which of the following is not a way to know when to change gears?
Use engine speed (rpm)
Use road speed (mph)
Watch your tachometer
Check that the pressure gauge shows normal oil pressure
Page 1 of 3
Next page

MA Air Brakes Test

Number of questions: 25
Correct answers to pass:20
Passing score:80%
Share This Online CDL Test
Rate this Air Brakes Test
4.7 out of 5
based on 187 votes