If you accidentally cross the air lines going to the trailer by mounting the blue line to the red line and vice versa, what will happen?

• Supply air will be sent to the service line instead of going to charge the trailer air tanks. Air will not be available to release the trailer spring brakes (parking brakes)
• The primary air tank will lose air pressure and the parking brake will apply automatically
• The trailer brakes will not work at all and you will hear a loud hissing sound as air escapes from the system
• Supply air will be sent to the emergency line instead of the service line and the emergency brakes will release. The lack of air going to the supply side will cause the trailer brakes to stop working.

If convicted of any traffic violations (except parking) you must inform your employer:

• Only if you feel it's a serious offense
• Within 30 days
• Within 60 days
• You do not have to inform your employer

To satisfy general cargo securement requirements, what is the minimum WLL for securing vehicles under 10,000 lbs?

• 4,500 lbs.
• 50% of the weight of the cargo.
• 10,000 lbs.
• 30% of the weight of the cargo.

If you drive ____ consecutive hours with no breaks, you can not drive a CMV until a 30-minute break is taken:

• 4
• 14
• 8
• 11

Why should you check your mirrors during a turn?

• To make sure the rear of your vehicle will not hit anything
• To see if you inverted the air lines
• To monitor the braking force to the rear of the trailer
• To see if the traffic behind you is turning

Which of the following statements are true about the parking brake control knob?

• Pull the parking brake control knob out to apply the parking brakes and push it in to release. The control will be a red, octagon-shaped knob labeled “trailer air supply” on newer vehicles.
• None of these are correct
• Pull the parking brake control knob out to apply the parking brakes and push it in to release. The control will be a yellow, diamond-shaped knob labeled “parking brakes” on newer vehicles.
• Push the parking brake control knob in to apply the parking brakes and pull it out to release. The control will be a yellow, diamond-shaped knob labeled “parking brakes” on newer vehicles.

ABS helps you avoid wheel lockup. How does it work?

• None of these are correct.
• The computer senses impending lockup and reduces the braking pressure to a safe level, and you maintain control.
• If your wheels begin to lock up, the computer will reduce the ratio of air pressure to volume, reducing brake pressure to a safe level, and you maintain control.
• If the hydraulic pressure gets too high, the ABS system will back off of the governor, reducing brake pressure to a safe level, and you maintain control.

What is low-speed offtracking?

• When taking off from a dead stop, the initial torque of the engine on the drivetrain will cause a slight offtracking of the tractor which could be a hazard to other traffic
• When a trailer's tandem axles are slightly out of alignment, the rear of the trailer will track off to one side or another instead of directly behind the tractor
• When making a high speed turn, the momentum carried by the trailer will cause it to swing wide and possibly outside the lane of travel
• When a combination vehicle makes a low-speed turn the wheels of the rearmost trailer axle follow a path several feet inside the path of the tractor steering axle.

You may or may not be able to stop faster with ABS, but you should be able to:

• Keep the steer tires from veering too hard and thus avoiding a rollover
• Steer around an obstacle while braking and avoid skids caused by over-braking.
• Lock up the wheels, which creates more traction on the roadway
• Keep the air brake fluid primed for maximum braking force

A device placed between the deck of a vehicle and car or between articles of cargo, intended to provide greater friction than exists naturally between these surfaces is:

• A friction mat.
• A cleat.
• Void filler.
• A chock.

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