Rhode Island CDL — Air Brakes Practice Test 5

11.The manual says brakes can drift out of adjustment quickly. Under what condition does it say this is especially likely?

When the truck sits parked overnightWhen the air tanks are fullWhen the ABS lamp is litWhen the brakes are hot

12.The air compressor on your truck has an oil supply of its own instead of running on engine oil. What does the manual tell you to do about it?

Drain the compressor oil at the end of every driving day, along with the air tanksNothing, because compressor oil is serviced only by a mechanicTop it up with engine oil each time the governor cuts the compressor outCheck the compressor's oil level before you start driving

13.Which pairing of warning device and its usual color matches the manual?

Low air pressure warning: usually a yellow light; ABS malfunction lamp: redLow air pressure warning: usually a green light; ABS malfunction lamp: blueLow air pressure warning: usually a red light; ABS malfunction lamp: yellowLow air pressure warning and ABS malfunction lamp: both red

14.You need to troubleshoot a brake adjustment problem on automatic slack adjusters. What should you consult first, and why?

The maker's own service manual, because adjusters from different manufacturers do not all work alikeThe ABS certification label, because it lists adjustment limitsThe application pressure gauge, because it shows adjuster wearNothing, because all automatic adjusters operate the same way

15.One half of your dual air brake system has dropped very low on pressure while the other half is normal. How does that affect stopping?

The front or rear brakes lose full effectiveness, so you need more distance to stopIt does not, because the other half takes over all the brakesOnly the trailer brakes are affectedYou will stop shorter because the spring brakes help out

16.Partway down a long grade, your application pressure gauge shows you need more and more pressure just to keep the same speed. What does this mean, and what should you do?

The air tanks are overfilled, so pump the pedal to bleed off pressure and hold your speedYour brakes are fading, so you should slow down and get into a lower gearThe spring brakes are dragging, so push the parking brake knob in firmly and carry onIt is normal on a grade, so keep steady pressure on the pedal until you reach the bottom

17.Your air compressor is driven by a belt. During the engine compartment part of your inspection, what does the manual have you check on that belt?

Only that it is the brand the maker installedIts condition and how tight it isIts color, which shows whether it is overheatingNothing, because compressor belts are checked only by a mechanic

18.A car suddenly pulls out in front of your truck, and your instinct is to hit the brakes. When does the manual call that a good response?

When there is enough room to stop and you brake correctlyAlways, since braking is the only safe choiceOnly when the truck has ABS on every axleNever, because you should always steer around instead

19.What is the safety relief valve on the first air tank there to prevent, and at about what pressure is it usually set to open?

Too little pressure for braking; about 60 psiToo much pressure in the system; about 150 psiWater building up in the tank; about 100 psiSpring brakes applying while you drive; about 45 psi

20.A Rhode Island applicant passes the Air Brakes knowledge test but takes the skills test in a truck that does not have a full air brake system. What happens?

Nothing, because passing the knowledge test is enoughAn L or Z restriction is still noted for vehicles with full air brakesThe applicant must retake the General Knowledge testThe applicant receives an E restriction instead