Wyoming CDL — Air Brakes: Safe Driving Practices Practice Test

Question 1

Which of these is NOT part of a normal stop as Section 5 describes it?

Accepted Answer

Pulling the parking brake knob out as the vehicle slows — A normal stop is made with the brake pedal alone: press it, control the pressure for a smooth stop, and pick a starting gear when stopped. With a manual transmission, the clutch stays out until engine rpm is near idle. The parking brake control plays no part.

Answer

Pushing the brake pedal down

Answer

Controlling the pressure so the stop is smooth and safe

Answer

Selecting a starting gear once the vehicle has stopped

Question 2

Which part of an air brake system is an electric switch that air pressure operates?

Accepted Answer

The stop light switch — The stop light switch is worked by air pressure and turns the brake lights on whenever the air brakes are applied, so drivers behind get a warning.

Answer

The air compressor governor

Answer

The safety relief valve

Answer

The alcohol evaporator

Question 3

Which of these is NOT part of the Air Gauge and Governor Cutoff Check, the first item in Section 11M's air brake check?

Accepted Answer

Holding the foot brake down for one minute — The first part has you chock the wheels, start the vehicle, see that the gauge works and that pressure builds to governor cutoff (roughly 120 to 140 psi), and identify your own vehicle's cutoff pressure. The one-minute hold on the foot brake belongs to the second part, the air leakage rate test.

Answer

Chocking the wheels

Answer

Confirming that the air gauge works

Answer

Identifying the cutoff pressure for your vehicle

Question 4

In Section 11M's air brake check, you finish the air leakage rate test and go straight to the air warning device test. What does the manual say about the engine at that point?

Accepted Answer

Do not restart it; leave the key or electrical power on — The warning device test is done with the engine still off. The key (or electrical power) is left switched to "on" or "battery charge" so the buzzer, light or flag can work while you fan the pressure down with the foot brake.

Answer

Restart it and hold a fast idle while you fan the brakes

Answer

Restart it only if the vehicle is a combination

Answer

Restart it, then shut it off once the gauge steadies

Question 5

On the vehicle inspection test you look over the air hoses and electrical lines at a tractor's coupling area. According to Section 11, what should NOT be showing through a hose?

Accepted Answer

Steel braid — Section 11 has you listen for air leaks and look over the hoses and electrical lines for cuts, chafing, splices and wear; a hose worn far enough to expose its steel braid fails. The lines also should not be tangled, pinched or dragging against the tractor.

Answer

The hose's color

Answer

The maker's label

Answer

The glad hand seal

Question 6

Your tank pressure dipped to the governor's cut-in level a moment ago and is now climbing through 115 psi. Going by the manual's approximate figures, what is the air compressor doing?

Accepted Answer

Pumping, and it will keep on until roughly 125 psi — The governor lets the compressor start pumping when tank pressure falls to cut-in, around 100 psi, and stops it at cut-out, around 125 psi. On the way up between those two levels the compressor is still pumping.

Answer

Resting, because pressure is already above 100 psi

Answer

Resting, because the safety valve has opened

Answer

Pumping, and it will not stop before 150 psi

Question 7

Which pair of tests in the Step 7 final air brake check does the manual have you begin by shutting the engine off?

Accepted Answer

The air leakage rate test and the low pressure warning signal test — Both the air leakage test and the low pressure warning test begin by turning the engine off. The governor check is run at a fast idle and the buildup check at operating rpm, so those two need the engine running.

Answer

The governor cut-in and cut-out check and the pressure buildup check

Answer

The parking brake test and the service brake test

Answer

The pressure buildup check and the service brake test

Question 8

Which of these does the manual actually credit ABS with?

Accepted Answer

Better control of the vehicle when you brake hard — ABS is an addition to the normal brakes. It neither adds to nor takes away from normal braking capability, it comes into play only when wheels are about to lock, and it does not necessarily shorten a stop. What it does is help you stay in control when you brake hard.

Answer

Always shortening your stopping distance

Answer

Raising the vehicle's normal braking capability

Answer

Working on every brake application, light or hard

Question 9

Your dual-system truck fails the Step 7 air pressure buildup check, even measured against the manufacturer's specifications. What does the manual tell you to do?

Accepted Answer

Do not drive until the problem is fixed — If pressure does not build fast enough, it can fall too low while you are driving and force an emergency stop. The manual's instruction is plain: get the problem fixed before you drive.

Answer

Drive, but keep below 45 mph

Answer

Drive, and watch the gauges closely

Answer

Drain the air tanks and then drive

Question 10

Section 11M has you look for fluid and air leaks at the front of the vehicle with the engine off. Why does it say an air leak matters?

Accepted Answer

It can point to a failed component in a spot that is hard to inspect, such as the air compressor — Section 11M says an air leak can signal that a part has failed somewhere you cannot easily see, and it names the air compressor and other air components as examples. The inspection itself covers the hoses and air lines, looking at their condition and for leaks.

Answer

It proves the governor's cut-out is set too high

Answer

It means the air tanks have been drained too often

Answer

It shows that the alcohol evaporator has run dry

Question 11

A truck tractor and a trailer, both with air brakes, were each built in June 1997. Going by the dates in the manual, which of them was required to have ABS?

Accepted Answer

Only the tractor — ABS became mandatory for air-braked truck tractors built from March 1, 1997 onward, but for other air-braked vehicles, trailers included, only from March 1, 1998. A June 1997 trailer could still have ABS, since many vehicles were fitted with it voluntarily.

Answer

Both of them

Answer

Only the trailer

Answer

Neither of them

Question 12

Which test in the Step 7 final air brake check is done with the vehicle rolling forward?

Accepted Answer

The service brake test — For the service brake test you let air pressure reach normal, take the parking brake off, creep forward at about 5 mph and brake firmly with the pedal. The leakage and warning tests start with the engine shut off, and the governor check only needs the engine running.

Answer

The air leakage rate test

Answer

The low pressure warning signal test

Answer

The governor cut-in and cut-out check

Wyoming CDL — Air Brakes: Safe Driving Practices practice test

Study questions with answers

1. Which of these is NOT part of a normal stop as Section 5 describes it?

2. Which part of an air brake system is an electric switch that air pressure operates?

3. Which of these is NOT part of the Air Gauge and Governor Cutoff Check, the first item in Section 11M's air brake check?

4. In Section 11M's air brake check, you finish the air leakage rate test and go straight to the air warning device test. What does the manual say about the engine at that point?

5. On the vehicle inspection test you look over the air hoses and electrical lines at a tractor's coupling area. According to Section 11, what should NOT be showing through a hose?

6. Your tank pressure dipped to the governor's cut-in level a moment ago and is now climbing through 115 psi. Going by the manual's approximate figures, what is the air compressor doing?

7. Which pair of tests in the Step 7 final air brake check does the manual have you begin by shutting the engine off?

8. Which of these does the manual actually credit ABS with?

9. Your dual-system truck fails the Step 7 air pressure buildup check, even measured against the manufacturer's specifications. What does the manual tell you to do?

10. Section 11M has you look for fluid and air leaks at the front of the vehicle with the engine off. Why does it say an air leak matters?

11. A truck tractor and a trailer, both with air brakes, were each built in June 1997. Going by the dates in the manual, which of them was required to have ABS?

12. Which test in the Step 7 final air brake check is done with the vehicle rolling forward?

More CDL — Air Brakes topics

Practice Safe Driving Practices in another state