Hawaii CDL — Air Brakes Practice Test 7

1.On the external inspection, what do you look for at each brake chamber?

That it is warm to the touchThat it is securely mounted, with no leaks, cracks or dentsThat it shows lining through an inspection openingThat it has 1/2 to 3/4 inch of play

2.You are ready to pull away in a newer air-braked truck, and the yellow, diamond-shaped parking brake knob is pulled out. What do you do to release the spring brakes?

Push the knob inPull the knob out a second notchTurn the knob a quarter turnPump the brake pedal three times

3.Which pairing of an air brake part with its job matches the manual?

Stop light switch: an air-operated electric switch that turns on the brake lightsSupply pressure gauge: shows how hard you are pressing the pedalSafety relief valve: sets the parking brakesGovernor: drains water from the tanks

4.Your truck's air tanks have automatic drains. What does the manual say about draining those tanks by hand?

It is never possible on a tank with an automatic drainIt ruins the automatic valveA tank with an automatic drain can also come fitted for hand drainingIt is required every hour in cold weather

5.Hawaii's restriction list includes Code L and Code Z, and both concern air brakes. How do they differ?

Code L applies only to trailers, and Code Z only to busesCode L bars air brake equipped CDL vehicles, while Code Z bars only CDL vehicles with full air brakesCode L is temporary, and Code Z is permanentCode Z bars all air brakes, while Code L bars only air over hydraulic systems

6.Two parts deal with pressure in the air tanks: the governor and the safety relief valve. Which description fits the manual?

The governor opens at 150 psi, and the safety valve restarts the compressor at 100 psiBoth are controls the driver sets from the cabThe safety valve decides when the compressor pumps, and the governor vents extra airThe governor decides when the compressor pumps, and the safety valve opens if pressure climbs too high

7.Your low air warning activates while you are driving. Besides telling you to stop, what does the manual say it might be a sign of?

An empty alcohol evaporatorThe governor reaching cut-outThe ABS activatingAn air leak in the system

8.The modulating control valve handle found on some dashboards is spring-loaded. What does the manual say the spring loading gives the driver?

A way to lock the lever for parkingA feel for the braking actionA backup supply of airAn automatic return to 'released' once the truck is parked

9.The low air pressure warning required on air-braked vehicles must be of what kind?

One you can hear, such as a buzzer, with a light being optionalOne you can see, with a buzzer as a possible additionOne you can feel through the brake pedalOne that shows only on the application pressure gauge

10.How does the manual say an air compressor may be kept cool?

Only by a dedicated electric fanBy air, or by the engine's cooling systemBy alcohol from the evaporatorBy the water that collects in the air tanks