Kansas CDL — Air Brakes Practice Test 5

11.In an emergency, you hand-adjust an automatic slack adjuster so you can get the truck to a repair shop. What should you expect afterward?

The adjuster is now repaired for goodThe adjuster will stay in manual mode from now onThe brake will probably slip out of adjustment again soon, because the cause hasn't been fixedThat brake will now apply harder than the others

12.On a long downgrade you keep leaning on the service brakes even after they start to fade. Where can that lead?

The ABS will take over and cool the brakesThe fade will stop once the drums finish expandingThe fade can keep growing until you can no longer slow or stop the vehicleThe spring brakes will hold you at a safe speed automatically

13.Which of these would NOT cause the spring brakes on an air-braked truck to apply?

Pulling out the parking brake control knobA leak that drains all the air from the systemPressing hard on the service brake pedalAir pressure falling into the 20 to 45 psi range

14.Air-operated disc brakes begin applying force the same way s-cam brakes do. Which two parts do they share for that job?

A brake chamber and a slack adjusterBrake shoes and a brake drumAn s-cam and a return springA wedge and a front brake limiting valve

15.You're about to pull an old trailer built before ABS was required, and you can't tell whether it was fitted with ABS. What does the manual suggest looking for underneath it?

A red air line running to the front of each brake chamberAn electronic control unit (ECU), plus wheel speed sensor wires running out of the rear of the brakesA second set of brake chambers mounted on every axleA blue diamond-shaped decal next to the trailer's air couplers

16.Halfway through a run, the yellow ABS malfunction lamp on your dash comes on and stays on. What does the manual advise?

You still have your regular brakes, so keep driving normally and get the ABS serviced soonPull over immediately, because the service brakes will no longer apply at allPump the brake pedal at every stop until the lamp goes back outSet the front brake limiting valve to 'slippery' to make up for the lost ABS

17.For an emergency stop in an air-braked vehicle, which two braking methods does the manual describe?

Pump braking and coast brakingEngine braking and parking-brake brakingControlled braking and stab brakingTrailer hand-valve braking and spring-brake braking

18.On an air-braked vehicle, during which step of the seven-step inspection do you check the slack adjusters, brake drums, linings, and brake chamber hoses?

Step 2, the engine compartment checksStep 5, the walk-around inspectionStep 7, the final air brake checkStep 1, the vehicle overview

19.Your air compressor is belt-driven. What should you check about the belt during the engine compartment step?

Only that a belt is presentThat it slips slightly at idle to protect the compressorIts condition and how tight it isThe part number printed on it

20.On a long downgrade, a couple of your truck's brakes are out of adjustment while the rest are properly adjusted. How does this lead to trouble?

The adjusted brakes lock up, which sets off the spring brakes on the drive axlesThe poorly adjusted brakes overheat first and turn on the ABS malfunction lampThe air compressor falls behind, so the tanks empty before the bottom of the gradeThe badly adjusted brakes stop pulling their weight, so the others overheat and fade