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MI CDL General Knowledge study materials
MI CDL General Knowledge study resources

MI CDL General Knowledge practice questions

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Question 1Driving Safely

Under Michigan CDL rules, which driving behavior is the clearest example of aggressive driving that a commercial driver must avoid?

  1. Following another vehicle too closely while speeding to keep a schedule Correct answer.
  2. Checking mirrors before slowing for a work zone
  3. Leaving extra following distance in rain
  4. Signaling a lane change well in advance

Explanation

Aggressive driving includes speeding, tailgating, and weaving in and out of traffic to save time. A commercial driver is held to a high standard because vehicle size and weight make the consequences severe. Safe habits like early signaling, mirror checks, and extra following distance are the opposite of aggressive driving.

Question 2Driving Safely

A CMV driver is convicted of a traffic violation in a personal vehicle. What is the driver's reporting responsibility to the employer?

  1. Report the conviction to the employer within 30 days Correct answer.
  2. Report only if the court requires it
  3. Report only if the violation occurred in a CMV
  4. Report only if points are added to the license

Explanation

Federal and Michigan rules require a driver to notify the employer of any conviction for a traffic violation, other than a parking violation, within 30 days. This applies even when the violation happened in a personal vehicle. The employer needs the information to keep the driver qualification file accurate.

Question 3Driving Safely

In Michigan, a commercial driver whose blood alcohol concentration is 0.04 percent while operating a CMV is:

  1. Allowed if the driver is off duty but still driving
  2. Only in violation if an crash occurs
  3. Under the legal limit because 0.08 applies to all drivers
  4. Legally intoxicated for CDL purposes and subject to disqualification Correct answer.

Explanation

The CDL alcohol threshold is 0.04 percent, which is lower than the 0.08 percent limit for non-commercial drivers. A CMV driver at or above 0.04 percent while operating a CMV is considered intoxicated and faces CDL disqualification. Off-duty status does not change the limit when the driver is operating a CMV.

Question 4Driving Safely

Which statement best describes how a driver should use the mirrors on a large CMV before changing lanes?

  1. Check both mirrors and the blind spots, then signal and move only when clear Correct answer.
  2. Signal first and change lanes while checking the mirror
  3. Rely on the convex mirror alone because it shows the widest view
  4. Look only at the flat mirror on the driver side

Explanation

Large vehicles have significant blind spots, and convex mirrors distort distance, making objects appear farther away than they are. A safe lane change requires checking both mirrors, confirming the blind spots, and signaling before moving. No single mirror gives a complete picture.

Question 5Driving Safely

When driving a CMV at highway speed, how much following distance should a driver generally maintain behind the vehicle ahead?

  1. Exactly two seconds regardless of vehicle length
  2. Half the distance shown on the speedometer in feet
  3. One car length for every 10 mph of speed
  4. At least one second for every 10 feet of vehicle length, plus one second for speeds over 40 mph Correct answer.

Explanation

The standard rule calls for one second of following distance for each 10 feet of vehicle length at speeds under 40 mph. Above 40 mph, add one additional second. A 60-foot vehicle at highway speed therefore needs at least seven seconds.

Question 6Driving Safely

A driver is descending a long, steep grade with a heavy load. Which technique protects the brakes from overheating?

  1. Apply the brakes hard and continuously at the top of the grade
  2. Ride the brakes lightly all the way down to hold a steady speed
  3. Shift to neutral to coast and save fuel
  4. Select a lower gear before the descent and use engine braking with controlled brake applications Correct answer.

Explanation

Descending in a lower gear lets the engine and gearing hold back the load, reducing reliance on the service brakes. The driver should choose the gear before the grade and use short, controlled brake applications. Continuous or hard braking builds heat and can cause brake fade or failure.

Question 7Driving Safely

When must a commercial driver place reflective warning triangles when stopped on a two-lane road?

  1. Within 10 minutes of stopping, placing them 10 feet, 100 feet, and 100 feet from the vehicle Correct answer.
  2. Only after 30 minutes have passed
  3. Only at night or during rain
  4. Only when the vehicle is on a shoulder

Explanation

Warning devices must be placed within 10 minutes of stopping on a two-lane road. The triangles go about 10 feet from the vehicle on the traffic side and about 100 feet ahead and behind. They are required whenever the vehicle is stopped on the roadway or shoulder.

Question 8Driving Safely

A driver must back a tractor-trailer into a loading dock. Which practice is safest?

  1. Back quickly to reduce time in the traffic lane
  2. Use a helper or spotter and back slowly, checking both mirrors Correct answer.
  3. Back using only the driver-side mirror
  4. Rely on the backup alarm to clear the area

Explanation

Backing a large vehicle is one of the highest-risk maneuvers because of the blind areas behind and beside the trailer. Using a spotter and backing slowly while checking both mirrors gives the driver the best awareness. Backup alarms help but do not guarantee that the area is clear.

Question 9Driving Safely

What is the proper way to handle a tire that blows out at highway speed on a CMV?

  1. Steer sharply toward the shoulder right away
  2. Accelerate briefly to stabilize the vehicle
  3. Brake hard immediately to stop as fast as possible
  4. Hold the steering wheel firmly, keep the vehicle straight, and slow gradually before pulling off Correct answer.

Explanation

A blowout at speed can pull the vehicle toward the failed tire, so the driver must grip the wheel firmly and keep the vehicle straight. Braking hard or steering sharply can cause a loss of control or a rollover. The driver should slow gradually and then move off the road when it is safe.

Question 10Driving Safely

In Michigan, when are headlights required on a commercial vehicle?

  1. Only on rural roads
  2. Only when other vehicles have their lights on
  3. Only between midnight and dawn
  4. From sunset to sunrise and whenever visibility is reduced, such as in rain, fog, or snow Correct answer.

Explanation

Headlights are required from sunset to sunrise and any time weather reduces visibility, including rain, fog, and snow. Michigan law also requires lights when visibility is limited, and many drivers use them whenever wipers are on. Lights help the driver see and help others see the CMV.

Question 11Driving Safely

A CMV approaches a railroad crossing with no gates and flashing signals that are not operating. What should the driver do?

  1. Follow the vehicle ahead closely across the tracks
  2. Stop, look both ways, listen, and proceed only when certain no train is coming Correct answer.
  3. Proceed without slowing because the signals are off
  4. Speed up to cross before a train appears

Explanation

When crossing signals are not working, the driver cannot rely on them and must treat the crossing as unprotected. The safe procedure is to stop, look and listen in both directions, and cross only when the tracks are clearly clear. Following another vehicle closely or rushing across is dangerous.

Question 12Driving Safely

How should a driver respond when a front tire starts to hydroplane on a wet road?

  1. Brake firmly to regain contact with the road
  2. Ease off the accelerator and avoid sudden braking or steering until traction returns Correct answer.
  3. Accelerate to push through the water
  4. Steer quickly to the side of the road

Explanation

Hydroplaning happens when water lifts the tires off the pavement, so sudden inputs can cause a skid or loss of control. The driver should ease off the accelerator, hold the wheel steady, and let speed drop until traction returns. Firm braking or sharp steering during hydroplaning can cause a crash.

Question 13Driving Safely

Which factor most increases the risk of a rollover in a commercial vehicle?

  1. Checking mirrors before a turn
  2. Taking a curve too fast with a high center of gravity Correct answer.
  3. Keeping the load low and centered
  4. Slowing before entering a ramp

Explanation

Rollovers are most often caused by speed carried into a curve combined with a high center of gravity. A tall, heavily loaded vehicle can tip when lateral force exceeds stability. Keeping loads low, slowing before ramps, and checking mirrors all reduce risk rather than increase it.

Question 14Driving Safely

A CMV driver is caught in a severe thunderstorm with limited visibility. What is the safest action?

  1. Slow down and, if visibility becomes too poor, pull off the road in a safe place and wait Correct answer.
  2. Maintain highway speed to clear the storm quickly
  3. Follow the taillights of the vehicle ahead closely
  4. Stop in the travel lane and turn on the hazard lights

Explanation

Heavy rain reduces visibility and traction, so the driver should reduce speed and increase following distance. If conditions become too dangerous, pulling completely off the road in a safe area and waiting is better than continuing. Stopping in a travel lane creates a collision hazard.

Question 15Driving Safely

What is the correct way to handle a vehicle fire that starts in the engine compartment of a CMV?

  1. Use the cargo to smother the flames
  2. Continue driving to the nearest fire station
  3. Stop, shut off the engine, get everyone away, and call for help before attempting any firefighting Correct answer.
  4. Open the hood fully to spray water on the flames

Explanation

A vehicle fire can spread quickly and produce toxic smoke, so the first priority is to stop, shut off the engine, and move people to safety. Emergency help should be called before any firefighting attempt. Opening the hood fully can feed oxygen to the fire and cause it to flare.

Question 16Driving Safely

A driver's vehicle is disabled on a divided highway. Where should warning triangles be placed?

  1. On the vehicle's roof for visibility
  2. About 50 feet behind the vehicle
  3. About 10 feet from the vehicle on the traffic side and about 200 feet behind and ahead Correct answer.
  4. Only directly behind the vehicle

Explanation

On a divided highway or one-way road, the devices are placed about 10 feet from the vehicle on the traffic side and about 200 feet to the rear and front. The longer distances give high-speed traffic time to react. Placing them too close or only behind the vehicle gives inadequate warning.

Question 17Driving Safely

Which statement about the effect of speed on stopping distance for a loaded CMV is accurate?

  1. Stopping distance increases in direct proportion to speed
  2. Stopping distance depends only on the driver's reaction time
  3. Stopping distance stays the same because brakes are sized for the load
  4. Stopping distance increases with the square of speed, so doubling speed roughly quadruples braking distance Correct answer.

Explanation

Kinetic energy rises with the square of velocity, so doubling speed greatly increases the distance needed to stop. A loaded CMV also needs more distance because of its mass and momentum. Drivers must plan braking early and maintain space ahead.

Question 18Driving Safely

A CMV driver sees a school bus stopped with its red lights flashing on an undivided road. What must the driver do?

  1. Slow down and pass with caution
  2. Honk to warn children and continue
  3. Pass only if no children are visible
  4. Stop and remain stopped until the red lights stop flashing Correct answer.

Explanation

On an undivided road, traffic in both directions must stop for a school bus with flashing red lights. The driver must wait until the lights stop flashing before proceeding. Passing a stopped school bus is dangerous and carries serious penalties.

Question 19Driving Safely

When should a driver use the engine brake, or retarder, on a CMV?

  1. At low speeds in city traffic to save fuel
  2. While backing into a loading dock
  3. On long downgrades to help control speed without overheating the service brakes Correct answer.
  4. In slippery conditions to slow the vehicle quickly

Explanation

Engine brakes and retarders help hold a steady speed on long downgrades and reduce reliance on the service brakes. They should not be used in slippery conditions because they can cause the drive wheels to lose traction. Local rules may restrict their use in certain areas.

Question 20Driving Safely

What does the term "blind spot" mean for a commercial driver?

  1. The area lit by the headlights
  2. A lane closed for construction
  3. A damaged section of the windshield
  4. An area around the vehicle that the driver cannot see directly or through the mirrors Correct answer.

Explanation

Blind spots are areas around a large vehicle that are not visible to the driver directly or in the mirrors. They are especially large on the right side and directly behind a trailer. Drivers must check blind spots carefully and use mirrors and spotters when maneuvering.

Question 21Driving Safely

A driver is being tailgated by a passenger car while driving a CMV. What is the safest response?

  1. Speed up well above the limit to create distance
  2. Change lanes without signaling to escape
  3. Brake sharply to warn the tailgater
  4. Increase the space ahead so you can slow gradually and avoid sudden stops Correct answer.

Explanation

When someone tailgates, the driver cannot control the other vehicle but can control the space ahead. Increasing following distance allows gradual speed changes and reduces the chance of a rear-end crash. Brake checking or speeding up increases danger.

Question 22Driving Safely

Which load securement practice is required before a CMV travels on Michigan roads?

  1. Only the rear of the load needs to be tied down
  2. Tiedowns are required only for loads over 10,000 pounds
  3. Cargo may be left loose if the vehicle travels slowly
  4. Cargo must be secured so it cannot shift or fall, using tiedowns rated for the load Correct answer.

Explanation

Cargo must be secured against shifting and falling, and the tiedowns must be strong enough for the weight and type of load. Loose or partially secured cargo can shift, cause a crash, or fall onto the road. The requirement applies regardless of vehicle speed.

Question 23Driving Safely

A driver must cross a bridge that is posted with a weight limit lower than the vehicle's gross weight. What should the driver do?

  1. Cross in a lower gear to spread the weight
  2. Do not cross and find an alternate route Correct answer.
  3. Cross only if no other traffic is on the bridge
  4. Cross slowly to reduce the load on the bridge

Explanation

A posted weight limit means the bridge is not rated for heavier vehicles, and crossing anyway risks structural failure. The driver must find another route or obtain lawful guidance. Speed or gear selection does not change the actual weight on the structure.

Question 24Driving Safely

What is the purpose of a pre-trip inspection before driving a CMV?

  1. To check the fuel level only
  2. To confirm the cargo is loaded
  3. To find defects that could cause a breakdown or crash before the vehicle is on the road Correct answer.
  4. To satisfy a paperwork requirement only

Explanation

A pre-trip inspection is a safety check of brakes, tires, lights, coupling devices, and other critical parts. Finding a defect before departure prevents breakdowns and crashes. It is more than paperwork and covers far more than fuel.

Question 25Driving Safely

A CMV driver is driving at night and an oncoming vehicle's high beams glare into the mirrors and windshield. What is the safest action?

  1. Close your eyes briefly to reduce the glare
  2. Look toward the right edge of the lane and slow down until the vehicle passes Correct answer.
  3. Turn on high beams in response
  4. Stare directly at the oncoming lights to judge distance

Explanation

Looking toward the right edge of the lane helps the driver stay positioned while avoiding direct glare. Slowing down gives more time to react while vision is reduced. Staring at the lights or retaliating with high beams increases danger.

Question 26Driving Safely

Under Michigan law, what is the maximum speed limit for a commercial motor vehicle on a freeway unless a lower limit is posted?

  1. 60 mph
  2. 65 mph Correct answer.
  3. 55 mph
  4. 70 mph

Explanation

Michigan sets the general freeway limit at 70 mph for passenger vehicles, but trucks are held to 65 mph unless a lower limit is posted. A driver should always obey the posted sign when it is lower than the truck limit.

Question 27Driving Safely

A driver is following a loaded tractor-trailer at 55 mph on a dry road. What following distance does the CDL manual recommend as a minimum under ideal conditions?

  1. One second for each 10 feet of vehicle length Correct answer.
  2. Three seconds at speeds under 40 mph only
  3. Two seconds regardless of vehicle length
  4. Four seconds only when carrying hazardous materials

Explanation

The recommended rule is one second per 10 feet of vehicle length at speeds under 40 mph, plus one additional second at higher speeds. A 60-foot combination at 55 mph therefore needs about seven seconds.

Question 28Driving Safely

Which condition requires a CMV driver to slow down by at least one-third below the posted speed limit?

  1. Driving through a work zone with workers present
  2. Driving on a gravel road
  3. Driving in a heavy rainstorm Correct answer.
  4. Driving at night on an unlit road

Explanation

The CDL manual states that a driver should reduce speed by one-third on wet roads. Rain reduces traction and lengthens stopping distance, so the adjustment is required even when the limit itself has not changed.

Question 29Driving Safely

What is the correct hand signal for a right turn when a CMV driver's turn signals fail?

  1. Left arm bent downward at the elbow
  2. Left arm straight out the window
  3. Left arm extended out and rotated in a circle
  4. Left arm bent upward at the elbow Correct answer.

Explanation

The standard hand signals are: straight out for a left turn, upward at the elbow for a right turn, and downward at the elbow for slowing or stopping. These signals must be used if the vehicle's lights are not working.

Question 30Driving Safely

A CMV is traveling in the right lane and the driver wants to change lanes. What is the correct procedure?

  1. Signal, check the mirrors, and move over while accelerating
  2. Rely on the convex mirror alone, since it shows the entire side of the vehicle
  3. Honk once, check the left mirror, and change lanes quickly
  4. Signal, check the mirrors, look over the shoulder for the blind spot, and change lanes when clear Correct answer.

Explanation

Lane changes require signaling, checking both flat and convex mirrors, and confirming the blind spot with a direct look before moving. The convex mirror shows a wider view but distorts distance, so it cannot replace a shoulder check.

Question 31Driving Safely

When entering a curve, what is the safest speed-control technique for a loaded CMV?

  1. Maintain the posted speed and brake at the exit
  2. Slow to a safe speed before the curve and accelerate gently after the midpoint Correct answer.
  3. Brake firmly while turning through the curve
  4. Shift to neutral and coast through the curve

Explanation

A CMV should be slowed before entering a curve because braking hard while turning can cause a rollover or skid. Gentle acceleration after the midpoint helps stabilize the vehicle as it exits.

Question 32Driving Safely

What is the correct way to start moving a CMV from a stop on an upgrade without rolling backward?

  1. Hold the vehicle with the service brake or parking brake, engage the clutch to the friction point, then release the brake as power takes hold Correct answer.
  2. Release the parking brake first, then engage the clutch quickly
  3. Use the trailer hand valve to hold the vehicle while releasing the clutch
  4. Rev the engine and drop the clutch to prevent rollback

Explanation

On a hill, the driver should hold the vehicle with the brake while engaging the clutch to the friction point, then release the brake as the engine begins to pull. This prevents rollback without slipping the clutch excessively.

Question 33Driving Safely

A driver must stop a CMV on the shoulder of a divided highway at night. Which action best helps other drivers see the vehicle?

  1. Turn on the four-way flashers and leave the headlights on Correct answer.
  2. Turn off all lights to avoid glare
  3. Leave the high beams on and point them at traffic
  4. Use only the parking lights

Explanation

Hazard flashers plus headlights make the stopped vehicle visible from both front and rear at night. Turning lights off or using only parking lights makes the CMV much harder to see.

Question 34Driving Safely

What does the term 'trailing' refer to when a driver is judging a safe gap in traffic?

  1. Watching a vehicle that has already passed to confirm it is clear behind you Correct answer.
  2. Backing a trailer into a tight space
  3. Passing a slower vehicle on the left
  4. Following another vehicle too closely

Explanation

Trailing means watching the vehicle that just passed you to see whether the lane behind it is clear before you change lanes. It is a technique for confirming the full gap, not just the space beside you.

Question 35Driving Safely

A CMV driver is being passed by another vehicle on a two-lane road. What should the driver do?

  1. Flash the headlights to warn oncoming traffic
  2. Brake sharply to let the passing vehicle in
  3. Speed up to shorten the passing time
  4. Move to the right edge of the lane and maintain speed Correct answer.

Explanation

When being passed, a driver should keep a steady speed and stay to the right so the passing vehicle has room. Speeding up or braking suddenly can cause a collision.

Question 36Driving Safely

What is the purpose of the 'stale green light' concept taught to CMV drivers?

  1. A light that is malfunctioning and flashing green
  2. A light that applies only to turning lanes
  3. A light that stays green during rush hour
  4. A green light that has been green for a long time and may change soon Correct answer.

Explanation

A stale green light is one that has been green long enough that it may turn yellow before the vehicle reaches the intersection. The driver should be prepared to stop rather than assume the right-of-way.

Question 37Driving Safely

A CMV approaches an intersection and the traffic light turns yellow. What is the safest decision?

  1. Stop abruptly regardless of traffic behind
  2. Stop if the vehicle can be brought to a safe stop before the line Correct answer.
  3. Accelerate to clear the intersection before red
  4. Proceed through the intersection while honking

Explanation

A yellow light means the signal is about to turn red, so the driver should stop if a safe stop is possible. A heavy CMV cannot stop quickly, so the decision must account for stopping distance and following traffic.

Question 38Driving Safely

When is a driver required to yield the right-of-way to another vehicle at an intersection with no signs or signals?

  1. When the other vehicle is a passenger car
  2. When the other vehicle is on the right Correct answer.
  3. When the other vehicle is moving faster
  4. When the other vehicle is on the left

Explanation

At an uncontrolled intersection, the driver must yield to vehicles approaching from the right. The rule prevents collisions when no signal or sign assigns priority.

Question 39Driving Safely

A driver is hauling a load that extends four feet beyond the rear of the vehicle. What is required during daylight hours?

  1. A reflective triangle at the end of the load
  2. No marking is required during daylight
  3. A red flag at least 12 inches square at the end of the load Correct answer.
  4. A flashing amber light at the end of the load

Explanation

Loads extending four feet or more beyond the rear must be marked with a red flag at least 12 inches square during daylight. At night, a red light or reflector is required instead.

Question 40Driving Safely

What should a driver check about a load before starting a trip?

  1. That the cargo matches the bill of lading only
  2. That the trailer doors are locked only
  3. That the load is secured against shifting and the vehicle is not overloaded Correct answer.
  4. Only that the tarps are clean

Explanation

Before driving, the driver must confirm the load is properly secured and within weight limits. Shifting cargo or an overloaded axle can cause loss of control or a crash.

Question 41Driving Safely

How should a driver distribute weight when loading a CMV with multiple axles?

  1. Place most weight over the steering axle
  2. Load all weight at the front of the trailer
  3. Spread the weight evenly so no axle is overloaded Correct answer.
  4. Concentrate the weight over the rear axle

Explanation

Weight should be distributed so that no axle exceeds its rated limit and the vehicle stays balanced. Overloading one axle affects steering, braking, and tire life.

Question 42Driving Safely

What is the effect of a heavy load on the center of gravity of a CMV?

  1. It has no effect on the center of gravity
  2. It lowers the center of gravity and reduces rollover risk
  3. It shifts the center of gravity forward only
  4. It raises the center of gravity and increases rollover risk Correct answer.

Explanation

A heavy load placed high raises the center of gravity, making the vehicle more likely to tip in curves or sudden maneuvers. Drivers must slow down and avoid abrupt steering with such loads.

Question 43Driving Safely

A driver is driving a CMV with a manual transmission down a long grade. What does the term 'gear fast, run slow' mean?

  1. Shift to the highest gear and maintain high speed
  2. Select a low gear before the grade so the engine holds the vehicle back Correct answer.
  3. Shift to neutral and use only the service brakes
  4. Use the clutch to control speed on the grade

Explanation

The phrase means the driver should be in a low enough gear to let engine braking control speed before the descent begins. Relying on service brakes alone can overheat them.

Question 44Driving Safely

What should a driver do if the brakes feel spongy or the pedal goes to the floor while driving?

  1. Shift to a lower gear, use the parking brake gradually, and stop in a safe place Correct answer.
  2. Ignore it until the next scheduled service
  3. Pump the brakes and continue to the destination
  4. Accelerate to build engine vacuum

Explanation

Spongy or failing brakes indicate a serious fault, so the driver should downshift, apply the parking brake gradually, and stop safely. Continuing to drive risks a total brake failure.

Question 45Driving Safely

When a CMV's rear wheels lock and the trailer begins to swing out during hard braking, what should the driver do?

  1. Apply the trailer hand valve and hold it
  2. Release the brakes to regain traction and steer in the direction of the skid Correct answer.
  3. Keep the brakes fully applied and steer opposite the skid
  4. Accelerate to pull the trailer straight

Explanation

Releasing the brakes lets the locked wheels roll again and restore steering control, and the driver should steer in the direction the rear is sliding. Holding the brakes or using the trailer hand valve worsens the jackknife.

Question 46Driving Safely

What is the correct action if a CMV driver's wheels drop off the pavement onto the shoulder?

  1. Accelerate to ride over the shoulder edge
  2. Steer sharply to the left immediately
  3. Brake hard and jerk the wheel back onto the pavement
  4. Hold the wheel firmly, slow gradually, and ease back onto the pavement when safe Correct answer.

Explanation

A driver should grip the wheel, slow gradually, and steer back gently once the lane is clear. Hard braking or sharp steering can cause a loss of control or rollover.

Question 47Driving Safely

A CMV driver is driving in fog and visibility drops to about 100 feet. What is the safest action?

  1. Turn on the four-way flashers and continue at normal speed
  2. Maintain the posted speed and use high beams
  3. Follow the taillights of the vehicle ahead closely
  4. Slow down, use low beams, and pull off the road if conditions worsen Correct answer.

Explanation

In dense fog, the driver should slow down, use low beams to reduce glare, and leave the road if visibility becomes too poor to drive safely. High beams and close following make the situation worse.

Question 48Driving Safely

What is the recommended action when a CMV driver becomes drowsy on a long trip?

  1. Stop in a safe place and take a rest break Correct answer.
  2. Increase speed to arrive sooner
  3. Open a window and turn up the radio
  4. Drink coffee and continue driving

Explanation

Drowsiness impairs reaction time and judgment, so the only reliable remedy is to stop and rest. Fresh air, music, or caffeine are temporary measures that do not restore alertness.

Question 49Driving Safely

A CMV driver's vehicle has a hydraulic brake system. What does a low fluid level in the reservoir most likely indicate?

  1. A normal condition that requires no action
  2. That the brakes are fully adjusted
  3. A leak somewhere in the brake system Correct answer.
  4. That the parking brake is engaged

Explanation

Hydraulic brake fluid does not normally drop unless there is a leak or worn components, so a low level signals a possible leak. The system should be inspected before the vehicle is driven.

Question 50Driving Safely

What should a driver do when approaching a drawbridge with a red signal showing?

  1. Stop only if another vehicle is waiting
  2. Proceed slowly if the bridge appears down
  3. Honk and continue across
  4. Stop and wait until the signal permits crossing Correct answer.

Explanation

A red signal at a drawbridge means the driver must stop and wait. The signal controls the crossing, and proceeding against it risks a fall or collision.