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California CDL DMV Knowledge Test Class B 2

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1. In a vehicle with dual air brakes, a leak in one system ____ the second system.
Will always affect
May not affect
Is caused by

A dual air brake system is made up of two separate air brake systems. If there is an air leak in one system, it may not affect the other.

2. When loading a trailer, weight should be:
Placed as high as possible.
Placed as low as possible.
Placed as far to the left as possible.

Cargo with a high center of gravity makes a vehicle more likely to tip over than cargo with a low center of gravity. For this reason, it is important that the weight of cargo be distributed as low as possible.

3. When adjusting your mirrors before a trip:
No part of your vehicle should be visible in any mirror.
Part of your vehicle should be visible in the mirrors.
More than half of each mirror should show the vehicle.

When properly adjusted, your mirrors should each display some part of your vehicle. Being able to see your own vehicle in your mirrors will give you a point of reference when judging the positions of other objects.

4. Drivers trapped behind a slow-moving vehicle often:
Follow the vehicle too closely.
Allow the vehicle plenty of space.
Are happy with the speed of travel.

It is common for drivers to tailgate slow-moving vehicles that cannot keep up with the speed of surrounding traffic. If you are being tailgated, allow the other driver to pass your vehicle.

5. Texting while driving is especially dangerous because:
It is both a mental and physical distraction.
A message may be upsetting to the driver.
People like to read and may become too engaged in their phones.

Texting while driving is particularly dangerous because it is both a mental and physical distraction to the driver. In addition to diverting a driver's mental attention away from the road, texting requires a person to remove at least one hand from the vehicle's controls.

6. A truck tractor built after March 1, 1997 must be equipped with:
An Anti-Lock Braking System (ABS).
A flag.
Hydraulic brakes.

Truck tractors with air brakes built on or after March 1, 1997 are required to be equipped with Anti-Lock Braking Systems (ABS).

7. When leaving a vehicle unattended, a driver should:
Always set the parking brake.
Only set the parking brake if the vehicle is parked on a slope.
Deflate the tires by 10 percent.

Always apply the parking brake when leaving your vehicle unattended.

8. During an applied leakage test, the maximum leakage rate for a double combination vehicle is:
10 psi in a minute.
8 psi in a minute.
6 psi in a minute.
4 psi in a minute.

It is important to know the maximum air loss rate that is safe for your specific vehicle. A double combination vehicle should have a leakage rate no higher than 4 psi in a minute during an applied leakage test.

9. Truck tractors with air brakes built on or after March 1, 1997 must have:
An Anti-Lock Braking System (ABS).

Truck tractors with air brakes built on or after March 1, 1997, and other vehicles with air brakes built on or after March 1, 1998, must be equipped with anti-lock brakes.

10. How should you brake if your vehicle's ABS is not working?
Brake normally, as you will still have functioning brakes.
Pump the brake repeatedly.
Press the brake pedal down as hard as you can.

Without a working Anti-Lock Braking System (ABS), your vehicle will still have normal brake function. Continue to drive and brake as you normally would and have your ABS serviced as soon as possible.

11. When completing an offset back/left parking maneuver, a driver should:
Pull straight forward, then back to the left.
Drive straight back, then pull forward to the left.
Pull straight forward, then drive straight back.

If you are asked to complete an offset back/left parking maneuver, you should first pull straight forward, then back up to the left. Your vehicle must be parked completely within the boundaries of the parking space.

12. As part of the vehicle inspection test, a CDL applicant may be asked to:
Check the engine oil level.
Replace a tire.
Remove the alternator belt.

When checking the engine compartment during the vehicle inspection test, you will need to check the engine oil level.

13. A danger of swerving to avoid a hazard while driving a large truck is that:
The truck may miss the object.
The truck may flip over.
The truck may stay in the same lane.

While swerving can sometimes be the safest way to handle a hazard on the roadway, doing so is not without risk. Top-heavy vehicles and tractors with multiple trailers may flip over in a swerve.

14. If the safety relief valve in the air brake system releases air:
The compressor needs more air.
There is something wrong with the brakes.
You may continue driving.

An air brake system has a safety relief valve, which releases air from the tanks if the pressure gets too high. If the valve must operate, something in the system is wrong and should be addressed by a mechanic.

15. Why should you regularly drain the air tanks?
Because the air gets old and needs to be replaced
Because compressed air contains some water and the water collects in the tanks
To allow for a change in pressure

Compressed air usually contains a certain amount of moisture and compressor oil, which can build up in the air storage tanks and damage the brake system. The tanks should be drained to clean out these accumulations. On a tank with a manual drain valve, draining should be performed at the end of each day of driving.

16. When parking, you should not use the parking brake if:
The brakes are very hot.
The brakes are very cold.
There is snow on the ground.

If your brakes are hot after coming down a steep grade, you should not use your parking brake when parking. Let your brakes cool before applying the parking brake or risk damaging the brakes.

17. When asked to make a lane change during the driving test, you should:
Make the change as soon as the examiner asks, without looking.
Use your turn signal and change lanes when safe.
Make the lane change as quickly as possible, even if that means cutting off another driver.

You will be asked to change lanes during the on-road driving test. When the examiner asks you to do this, you should make the necessary traffic checks and use the proper signals before changing lanes.

18. A cardboard box on the roadway:
Should be expected to be on the roadway.
Is usually empty and harmless.
Could contain a heavy object that could damage vehicles.

Almost any foreign object on the road poses some potential danger. For example, even something as seemingly harmless as a cardboard box could contain a hard or heavy object that could damage your vehicle.

19. When inspecting the windshield before a trip, a person should do all the following, except:
Remove and sharpen the wiper blades.
Check the windshield wipers for proper spring tension.
Check the wiper blades for damage.

When inspecting your windshield, you should look for cracks or other problems that could interfere with your ability to clearly see the road. The windshield wiper arms should be checked for proper spring tension. The wiper blades should be checked for damage, stiff rubber, and improper securement.

20. When inspecting your tires, you do not want to find:
Tire tread that is 4/32 of an inch deep.
Valve stems without damage.
Mismatched tire sizes.

There should be at least 4/32 of an inch of tread depth in every major groove on front tires and 2/32 of an inch on other tires. Valve stems should not be cut or cracked. Tire sizes should not be mismatched.

21. During a walk-around inspection, ensure there are no cracks on the brake drums that are more than ____ of the width of the friction area.
One half
One quarter
One third

Before beginning a trip, it is important to check the brake drums during your walk-around inspection. It is unsafe to drive if any brake drum has a crack more than one half of the width of the friction area.

22. Rust around wheel nuts may mean:
It has rained recently.
The nuts could be loose.
The tires should be replaced.

Rust around wheel nuts may mean that they are loose. Check the tightness of the nuts if you see any rust in the area.

23. When accelerating on a surface with poor traction, such as a wet road, a driver should:
Speed up quickly.
Speed up slowly.
Not be concerned about the pavement.

You should accelerate very gradually when driving under conditions that create poor traction.

24. If you are disqualified from driving:
Your employer will be notified by the state.
You must notify your employer within two business days.
You must notify your employer within a month.

You must notify your employer within two business days if your license is suspended, revoked, or canceled, or if you are otherwise disqualified from driving.

25. A ____ allows a driver to gradually apply spring brakes.
Modulating control valve
Trailer air supply control
Relay valve

A modulating control valve allows a driver to gradually apply spring brakes. In equipped vehicles, the valve is controlled by a lever located on the dashboard.

26. During the driving test, when asked to make a lane change:
You should not be concerned with other motorists.
You should use your turn signal and change lanes when safe.
You should make the lane change as quickly as possible, even if that means cutting off another driver.

When asked to make a lane change during the on-road driving test, you should make the proper traffic checks, use your turn signal, and smoothly change lanes when it is safe to do so.

27. A one-way check valve:
Drains the water and compressor oil from the air tanks.
Prevents air from escaping if the air compressor has a leak.
Activates the emergency brakes when there is a leak.

A one-way check valve is required to be between an air compressor and the first main reservoir. This valve prevents air from escaping the system if the air compressor develops a leak.

28. If you are taking the driving test and the route does not include a railroad crossing, you:
Will not have to do anything related to a crossing.
May have to explain how you would cross railroad tracks.
Will have to take a different route.

During the on-road driving test, if your route does not include a railroad crossing, the examiner may ask you to explain and demonstrate the necessary procedures at a simulated location.

29. Cargo being transported should be checked:
Only before the trip.
Before the trip and again within the first 50 miles of the trip.
Only by the loading personnel.

Cargo should be inspected before beginning a trip, within the first 50 miles of the trip, and every three hours or 150 miles traveled thereafter. Cargo should be inspected every time the driver stops to take a break. The driver of a truck transporting cargo is responsible for the cargo being safely secured throughout the trip.

30. While driving, gauges are:
To be monitored for potential signs of trouble.

While driving, you should watch your vehicle's gauges for signs of trouble. Be sure to inspect your gauges before beginning a trip to ensure that they are in proper working order.

31. Who is responsible for cargo that has been loaded onto a truck?
The person who loaded the truck
The supervisor of the company
The truck driver

Even if they did not load or secure the cargo themselves, the driver of a vehicle is responsible for inspecting the cargo and ensuring that it is properly secured.

32. A jogger wearing a stereo headset:
Is probably aware of what is happening around them.
May not be aware of what is happening around them.
Can hear the sounds of traffic.

Be careful around pedestrians, joggers, and cyclists who are wearing headphones. They may be unable to hear your vehicle approaching and may do dangerous things because they do not know you are there.

33. If an air compressor is belt-driven, the belt should be routinely checked to ensure that it is:
Properly tightened.

If your vehicle has air brakes, the air compressor drive belt should be checked before each drive. Check the tightness of the belt and verify that it is in good condition.

34. When starting an engine, oil pressure should come up to a normal level:
Within seconds.
Within five minutes.
After about three minutes.

Look at your truck's gauges when starting the engine. The oil pressure in an engine should come up to a normal level within seconds of the vehicle's engine being started.

35. Your horn should be used to:
Tell other drivers that you are angry.
Warn other drivers that you are near.
Frighten other drivers.

Your vehicle's horn is a tool to warn others of your presence. Because the horn may create danger by startling other drivers, you should use it only if necessary.

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