Maine CDL — Air Brakes Practice Test 1

1.Several parts of the Step 7 final air brake check have you pump the brake pedal so that tank pressure comes down. Which of these checks does NOT work that way?

Finding the governor's cut-in pressureTesting the low pressure warning signalChecking the rate of air pressure buildupChecking that the spring brakes apply on their own

2.How does the manual's final air brake check have you confirm that the parking brake will hold?

Stop, set the parking brake, and pull gently against it in a low gearSet the parking brake at about 20 mph and time the stopSet the parking brake and stand on the brake pedal with full forcePark on a steep hill, shut off the engine, and see whether the vehicle rolls

3.A new driver believes the governor sets how hard the brakes apply when the pedal is pressed. What does the governor actually do?

It decides how much air reaches the front brakes on slick roadsIt controls when the compressor pumps air into the storage tanksIt opens to vent the tanks when pressure gets dangerously highIt turns on the brake lights when the pedal goes down

4.Maine's inspection test section explains why the air lines running from the power unit to the trailer matter. What does it say losing the air supply to the trailer will lead to?

The trailer brakes harder than the tractor doesThe tractor's ABS lamp switches offThe governor raises its cut-out pressureThe towed unit loses some or all of its braking

5.One part of the final air brake check confirms that the spring brakes apply on their own. As you keep fanning off air on a tractor-trailer, which controls should pop out when pressure falls to the manufacturer's specification?

Only the parking brake valveOnly the tractor protection valveBoth the tractor protection valve and the parking brake valveNeither, because the valves on a combination never pop out

6.A Maine driver wants an air brake restriction taken off a CDL. Which of these is NOT part of what the Maine manual requires?

Applying for the changeQualifying on the air brake knowledge testQualifying on a skills test in a vehicle that has air brakesWaiting one full year after the restriction was issued

7.According to the Maine manual, which two things must an applicant do to keep the air brake restriction off a CDL?

Qualify on the air brake part of the exam and take the skills test in a vehicle that has air brakesPass the general knowledge test twice and hold a permit for a full yearTake the skills test in any vehicle and hand in a mechanic's letter about air brakesPass the hazardous materials test and a second vision screening

8.Some wedge brakes use two brake chambers instead of one. Where do the wedges push in that design?

At each end of the brake shoesAgainst the outside of the brake drumBetween the slack adjuster and the s-camAgainst the disc, from opposite sides

9.On Maine's inspection test, the trailer brake check has you pull gently forward with the trailer parking brake set and the power unit's parking brake released. Besides showing that the trailer brake holds, what does the manual say this check assists with?

Measuring the governor cut-out pressureDraining moisture from the trailer air tankChecking that the trailer coupling is connectedSetting the automatic slack adjusters

10.A Maine driver whose CDL carries the air brake restriction is asked to cover a shift in a dump truck that has air brakes. What does the Maine manual say about that?

It is allowed for trips that stay inside MaineIt is allowed if the employer signs a waiverIt is not allowed, because the restriction bars the driver from operating air brake equipped vehiclesIt is allowed as long as the truck pulls no trailer