Delaware CDL — Air Brakes Practice Test 10

11.Your test vehicle has a backup air system. What does Delaware's manual say you need to do during the emergency brake test?

Tell the examiner the vehicle has a backup system, so its valves will not pop outSkip the test without saying anythingDisconnect the backup tank before startingKeep fanning the brakes until the valves pop out anyway

12.You are checking the governor's cut-out pressure during the final air brake check. How should the engine be running?

Shut off, with the key onAt a fast idleAt full throttle with the transmission in gearAt the slowest idle it will hold

13.A pickup cuts across your lane with little warning, and your instinct is to hit the brakes. When does the manual call that a good response?

Always, no matter how little room there isOnly when the vehicle has ABS on every axleNever; the manual says to steer around insteadWhen you have enough room to stop and you brake correctly

14.Two of your brakes are out of adjustment as you work down a long grade. What does the manual say happens to the others?

They do less work, so they stay coolerThey pick up the extra load and can overheat and fadeThey lock up automaticallyNothing changes as long as air pressure is normal

15.For the L restriction on a CDL, what does the manual count as 'air brakes'?

Any brake system that works wholly or partly on the air brake principleOnly systems that run entirely on airOnly the spring brakesOnly the brakes on a trailer

16.In an emergency, you manually adjust an automatic slack adjuster so you can get off the road. Why does the manual treat this as only a temporary measure?

The adjuster locks up after a single manual adjustmentThe brake is likely to drift out of adjustment again soon, because the real fault has not been fixedManual adjustment releases the spring brakesThe low air warning stops working afterward

17.A modulating control valve lets the driver bring the spring brakes on gradually. Why does the manual say it works that way?

It gives the driver a controllable way to stop with the spring brakes after a service brake failureIt lets the parking brakes be set without using any airIt gives the compressor time to cut inIt makes the trailer brakes apply ahead of the tractor brakes

18.During the emergency brake test on Delaware's inspection test, your vehicle has valves that do not pop out by design. How do you tell that the parking or emergency brakes have applied?

Watch for the ABS lamp to lightWait for the low air buzzer to go quietCheck that the governor cuts inListen for air discharging from the air system

19.What does the manual say is the likely result of routinely adjusting most automatic slack adjusters by hand?

The adjuster itself wears out earlyAir pressure builds fasterThe brake drums crackThe governor sticks at cut-out

20.On a vehicle with air brakes, what takes the place of the hydraulic brake check in Step 7 of the seven-step inspection?

The final air brake check laid out in the Air Brakes sectionNothing; Step 7 is skipped on air-braked vehiclesA second walk-around inspectionA repeat of the engine compartment check