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Alabama CDL School Bus Test study materials
Alabama CDL School Bus Test study resources

Alabama CDL School Bus Test practice questions

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Question 1Vehicle Inspection

Before starting a school bus, the driver should verify that the parking brake is engaged and the transmission is in which position?

  1. Reverse
  2. Drive
  3. Low range
  4. Neutral or park Correct answer.

Explanation

A bus should be started with the parking brake set and the transmission in neutral or park so the vehicle cannot lurch when the engine catches. This keeps the bus stationary until the driver is ready to move.

Question 2Vehicle Inspection

During the pre-trip inspection, the slack adjusters on a bus with air brakes should have no more than about how much free play when pulled by hand?

  1. One inch Correct answer.
  2. Three inches
  3. Two inches
  4. Half an inch

Explanation

A common rule is that a properly adjusted slack adjuster should move no more than about one inch when pulled by hand. Excessive free play signals the brakes need adjustment before the trip.

Question 3Vehicle Inspection

When checking the emergency exit door on a school bus, what should the driver confirm?

  1. That the glass is tinted
  2. That it opens freely and the buzzer sounds Correct answer.
  3. That it is locked from the outside
  4. That it stays latched with the handle removed

Explanation

Emergency exits must open smoothly from the inside and the warning buzzer must sound when the handle is released. Both features confirm passengers could escape and the driver would be alerted.

Question 4Vehicle Inspection

The tread depth on the front tires of a school bus must be at least:

  1. 1/32 of an inch
  2. 2/32 of an inch
  3. 6/32 of an inch
  4. 4/32 of an inch Correct answer.

Explanation

Front steering tires are held to a deeper minimum tread depth of 4/32 inch because they carry steering control. All other tires must meet at least 2/32 inch.

Question 5Vehicle Inspection

While performing the in-cab inspection, the driver finds the ABS warning light stays on after the engine starts. What does this indicate?

  1. The seat belt is unbuckled
  2. The air pressure is too high
  3. The parking brake is still set
  4. The anti-lock brake system has a fault Correct answer.

Explanation

An ABS lamp that remains lit after start-up means the anti-lock system has detected a malfunction. The bus should be reported and not placed in service until the fault is corrected.

Question 6Vehicle Inspection

When checking the bus's mirrors before a trip, the driver should adjust the crossover mirror so that the driver can see:

  1. The area in front of the bus and the front bumper Correct answer.
  2. The passenger seats
  3. The sky above the bus
  4. Only the rear wheels

Explanation

Crossover mirrors are aimed to reveal the blind spot directly in front of the bus, including the front bumper area where children may stand. Proper aim lets the driver spot a child before moving.

Question 7Vehicle Inspection

During the engine compartment check, the driver notices the power steering fluid is below the minimum mark. What is the correct action?

  1. Top it off with engine oil
  2. Add fluid and report the low level Correct answer.
  3. Continue the route and check it later
  4. Ignore it since buses use electric steering

Explanation

Low power steering fluid can cause loss of steering assist, so it must be brought to the proper level and the condition reported. Continuing with a known low level risks a steering failure.

Question 8Vehicle Inspection

When performing the brake test on a bus with air brakes, the driver should check that air pressure builds from 85 to 100 psi within what time frame?

  1. About 5 minutes
  2. About 45 seconds Correct answer.
  3. About 2 seconds
  4. About 10 minutes

Explanation

The buildup test expects pressure to rise from 85 to 100 psi in roughly 45 seconds at operating rpm. A slower buildup points to a compressor or leak problem that needs attention.

Question 9Vehicle Inspection

The driver applies the parking brake during the pre-trip and finds the bus rolls slightly on a slope. What should the driver do?

  1. Have a passenger hold the brake
  2. Continue but avoid hills
  3. Chock the wheels and drive anyway
  4. Tag the bus out of service and report the defect Correct answer.

Explanation

A parking brake that will not hold the bus is a safety defect that must be corrected before the vehicle is used. The bus should be removed from service and the problem reported.

Question 10Vehicle Inspection

What is the purpose of the pre-trip inspection of the bus's stop arm?

  1. To check its paint color
  2. To confirm it extends fully and is visible Correct answer.
  3. To weigh the arm
  4. To test the radio

Explanation

The stop arm must extend completely and be clearly visible so traffic is warned when children cross. A sticking or broken arm defeats its safety purpose.

Question 11Vehicle Inspection

While checking the lights, the driver finds the right rear turn signal does not flash. What is the correct response?

  1. Repair or replace the bulb before driving Correct answer.
  2. Report it after the route
  3. Turn only in daylight
  4. Use hand signals instead

Explanation

All required lamps, including turn signals, must work before the bus is operated. A non-functioning signal must be corrected before the trip begins.

Question 12Vehicle Inspection

When checking the bus's tires, the driver should look for which condition that would require the tire to be removed from service?

  1. A deep cut exposing the cord Correct answer.
  2. A small amount of dust
  3. A slightly warm tread
  4. A valve stem cap

Explanation

Cuts deep enough to expose body cords weaken the tire and make it unsafe. Such a tire must be replaced before the bus is driven.

Question 13Vehicle Inspection

During the in-cab check, the driver presses the foot brake and the low air warning buzzer sounds at approximately what pressure?

  1. 60 psi Correct answer.
  2. 90 psi
  3. 150 psi
  4. 120 psi

Explanation

The low air warning should activate before pressure drops below about 60 psi so the driver has time to stop safely. A warning that fails to sound at that level indicates a defect.

Question 14Vehicle Inspection

What should the driver confirm about the bus's heater and defroster during the pre-trip inspection?

  1. They make noise when off
  2. They function to keep the windshield clear Correct answer.
  3. They are set to maximum heat
  4. They are disconnected

Explanation

A working defroster keeps the windshield clear so the driver can see, which is essential for safe operation. The heater and defroster should be tested during the inspection.

Question 15Vehicle Inspection

When the driver checks the bus's emergency equipment, which item must be present and ready for use?

  1. A flashlight only
  2. A spare tire iron
  3. A tool kit
  4. A properly charged fire extinguisher Correct answer.

Explanation

A charged fire extinguisher is required emergency equipment on a school bus and must be mounted and ready. Missing or discharged extinguishers make the bus unfit for service.

Question 16Vehicle Inspection

The driver checks the bus's battery compartment and finds loose cables. Why is this a concern?

  1. Loose cables can cause a loss of power or a fire Correct answer.
  2. Loose cables reduce tire wear
  3. Loose cables are required for airflow
  4. Loose cables improve starting

Explanation

Loose battery connections can arc, causing power loss or a fire, and should be tightened before operation. Secure connections are part of a sound electrical system.

Question 17Vehicle Inspection

What should the driver verify about the bus's exhaust system during the pre-trip inspection?

  1. It is secure and free of leaks Correct answer.
  2. It is painted black
  3. It is removed for cleaning
  4. It points upward

Explanation

A secure, leak-free exhaust keeps carbon monoxide away from passengers and the driver. Leaks or loose hangers must be corrected before the bus is used.

Question 18Vehicle Inspection

During the walk-around, the driver notices the bus's front bumper is cracked and loose. What is the appropriate action?

  1. Ignore it since it is cosmetic
  2. Remove the bumper
  3. Tape it and drive
  4. Report and repair it before operating Correct answer.

Explanation

A loose or cracked bumper is a structural safety concern that must be repaired before the bus carries passengers. It should be reported and fixed, not patched.

Question 19Vehicle Inspection

When checking the bus's steering, the driver should look for which condition?

  1. A firm feel with little movement
  2. Power steering fluid color
  3. A steering wheel cover
  4. Excessive play in the steering wheel Correct answer.

Explanation

Excessive free play in the steering wheel indicates worn steering components and must be corrected before driving. Steering should feel firm with only limited play.

Question 20Vehicle Inspection

What is the correct way to check the bus's coolant level during the pre-trip inspection?

  1. Open the radiator cap while hot
  2. Check the overflow reservoir when the engine is cool Correct answer.
  3. Rely on the temperature gauge only
  4. Taste the coolant

Explanation

Coolant should be checked at the overflow reservoir with the engine cool to avoid burns from pressurized hot fluid. The gauge alone does not confirm the level.

Question 21Vehicle Inspection

When the driver checks the bus's service door, what should be confirmed?

  1. It stays open while driving
  2. It opens and closes smoothly and latches securely Correct answer.
  3. It has no glass
  4. It requires two people to operate

Explanation

The service door must operate smoothly and latch securely so it does not swing open while the bus is moving. A door that will not latch is a safety defect.

Question 22Vehicle Inspection

The driver is checking the bus's stop lights and finds the brake lights work but the tail lights do not. Why is this a problem?

  1. Tail lights charge the battery
  2. Tail lights make the bus visible from behind at night Correct answer.
  3. Tail lights operate the stop arm
  4. Tail lights power the turn signals

Explanation

Tail lights make the bus visible to traffic behind it in low light, so a failure must be repaired before driving. Brake lights working does not cover the tail light function.

Question 23Vehicle Inspection

During the pre-trip inspection, the driver checks the bus's mud flaps and splash guards. What is the purpose of this check?

  1. To weigh them
  2. To confirm they are painted
  3. To remove them for cleaning
  4. To ensure they are secure and not damaged Correct answer.

Explanation

Mud flaps and splash guards must be secure and intact to control spray and debris thrown toward other vehicles. Loose or missing guards are a defect.

Question 24Vehicle Inspection

The driver completes the pre-trip inspection and finds the bus's horn does not sound. What should the driver do?

  1. Honk later to test it
  2. Drive only on quiet roads
  3. Use the radio to warn others
  4. Repair it before operating the bus Correct answer.

Explanation

A working horn is required equipment for warning others of danger, so it must be repaired before the bus is operated. Driving without it leaves the bus out of compliance.

Question 25Vehicle Inspection

When checking the bus's air brake system, the driver performs a static leak test. A steady drop in pressure with the brakes applied indicates:

  1. An air leak that must be repaired Correct answer.
  2. The brakes are fully adjusted
  3. Normal operation
  4. The compressor is overworking

Explanation

A pressure loss during the static leak test means air is escaping somewhere in the system, which must be found and repaired. Normal systems hold pressure without a steady drop.

Question 26Vehicle Inspection

How far should the driver walk around the bus to inspect it during the pre-trip inspection?

  1. A half circle covering only the driver side
  2. Two trips focused only on the tires
  3. A short walk from the door to the rear bumper
  4. One complete trip around the bus, checking all systems along the way Correct answer.

Explanation

A complete walk-around lets the driver observe every side, the roof line, and the undercarriage areas that cannot be seen from the seat. Skipping sections leaves defects undiscovered.

Question 27Vehicle Inspection

What should the driver check about the bus's windshield before beginning a trip?

  1. That it carries a spare windshield in the bus
  2. That it is clean, free of cracks, and has working wipers Correct answer.
  3. That it is tinted darker than the side windows
  4. That it is propped open for ventilation

Explanation

A clear, undamaged windshield with functioning wipers and washers is required for safe visibility. Cracks or dirty glass obstruct the driver's view of the roadway and students.

Question 28Vehicle Inspection

During the pre-trip inspection, what should the driver confirm about the bus's emergency exit doors?

  1. They are painted a different color than the body
  2. They open only with a key held by the driver
  3. They open freely from the inside and their warning buzzer sounds Correct answer.
  4. They are locked from the inside to prevent student use

Explanation

Emergency exits must operate from the inside without special tools or keys, and the warning device must alert the driver if one is opened. This ensures students can escape in an emergency and the driver knows if an exit is unlatched.

Question 29Vehicle Inspection

What is the correct way for the driver to check the bus's hydraulic brake fluid level?

  1. Check the level only after the engine has run for an hour
  2. Estimate the level by pressing the brake pedal twice
  3. Read the reservoir against its full and minimum markings with the bus level Correct answer.
  4. Fill the reservoir to the top of the cap threads

Explanation

The reservoir has marked full and minimum levels, and the vehicle should be on level ground for an accurate reading. Overfilling or guessing can hide leaks or cause spillage.

Question 30Vehicle Inspection

What should the driver verify about the bus's backup lights during the pre-trip inspection?

  1. They flash whenever the service door opens
  2. They stay on continuously while the engine runs
  3. They illuminate only when the hazard switch is on
  4. They come on when the transmission is placed in reverse Correct answer.

Explanation

Backup lights are wired to the reverse gear position and warn others that the bus is about to move backward. Having a helper observe the lights while the driver shifts into reverse confirms they work.

Question 31Vehicle Inspection

During the pre-trip inspection, the driver should check that the bus's passenger seats are:

  1. Upholstered in a single uniform color
  2. Folded up to allow standing passengers
  3. Securely fastened to the floor with no broken frames Correct answer.
  4. Numbered in order from front to back

Explanation

Seats that are loose or have cracked frames can break free in a crash or sudden stop and injure students. Fasteners and frame condition are the items that matter for safety.

Question 32Vehicle Inspection

What should the driver check about the bus's fuel level before starting a route?

  1. That the tank is filled to the exact top
  2. That the fuel cap has been removed
  3. That there is enough fuel to complete the trip Correct answer.
  4. That the fuel gauge reads below one quarter

Explanation

The driver must have sufficient fuel to finish the route without running out, which is especially important on routes with students aboard. Running low can strand the bus and create an unsafe situation.

Question 33Vehicle Inspection

Why does the driver check that the bus's registration and inspection documents are on board?

  1. They list the names of the students riding the bus
  2. They authorize the driver to exceed speed limits
  3. They are required to be carried in the vehicle and show it is legally operable Correct answer.
  4. They prove the driver has paid for fuel

Explanation

Required documents must be carried in the vehicle, and valid registration and inspection show the bus is authorized for service. Operating without them can result in the bus being placed out of service.

Question 34Vehicle Inspection

The driver finds the bus's left headlight is dimmer than the right one. What is the most likely cause the driver should have corrected?

  1. The right headlight is a different brand
  2. The bus is parked on a slope
  3. The battery is fully charged
  4. A poor ground or corroded connection at the lamp Correct answer.

Explanation

A dim lamp usually indicates high resistance from a bad ground or corroded connector, which reduces current flow. This must be repaired before the bus is used because it limits the driver's visibility and makes the bus harder for others to see.

Question 35Vehicle Inspection

During the pre-trip, the driver notices the bus's air pressure gauge rises very slowly during the build-up check. What should the driver conclude?

  1. The bus has too much air in the system
  2. The slow rise means the brakes are adjusted correctly
  3. The gauge is designed to rise slowly and no action is needed
  4. The compressor or a related component may be faulty and the bus should not be used Correct answer.

Explanation

Air pressure must build at a normal rate; a slow build points to a weak compressor, a leak, or a restricted line. The defect must be reported and the bus taken out of service until repaired.

Question 36Vehicle Inspection

The driver checks the bus's brake pedal and finds it feels spongy and travels nearly to the floor. What does this indicate?

  1. The tires are overinflated
  2. The parking brake is set correctly
  3. Air in the hydraulic system or a fluid leak that needs repair Correct answer.
  4. The bus is due for a routine oil change

Explanation

A spongy pedal that sinks indicates air in the hydraulic lines or a fluid leak, which reduces braking force. The bus must not be driven until the brake system is repaired and bled.

Question 37Vehicle Inspection

While inspecting the bus's tires, the driver finds a tire with tread worn down to the wear indicator bars. What is the correct action?

  1. Continue using it until the next scheduled service
  2. Move the tire to the front axle for better traction
  3. Remove the tire from service and replace it before the route Correct answer.
  4. Reduce the air pressure to extend tread life

Explanation

Tread at the wear bars no longer provides adequate traction, especially on wet roads, and the tire must be replaced. Moving a worn tire to another position does not restore its tread.

Question 38Vehicle Inspection

The driver checks the bus's mirror brackets and finds one bracket is loose and vibrates. Why must this be corrected before driving?

  1. It changes the bus's turning radius
  2. A vibrating mirror blurs the view and the assembly may fail Correct answer.
  3. It causes the turn signals to blink faster
  4. It makes the bus louder inside the cabin

Explanation

Loose mirror brackets let the mirror vibrate, which blurs the reflected image and prevents the driver from seeing students and traffic clearly. A loose bracket can also break free entirely.

Question 39Vehicle Inspection

During the pre-trip, the driver finds the bus's stop arm extends but does not retract fully. What is the appropriate response?

  1. Ignore it because the stop arm is optional equipment
  2. Tag the bus out of service until the stop arm is repaired Correct answer.
  3. Drive the route and retract the arm by hand at each stop
  4. Remove the stop arm for the day and continue

Explanation

A stop arm that fails to retract fully is a defect that can strike objects or people and signals a mechanical failure. The bus should be removed from service and the defect repaired before carrying students.

Question 40Vehicle Inspection

The driver checks the bus's coolant and finds it is low with no visible puddle under the bus. What should the driver do?

  1. Add water only and continue the route
  2. Assume the level is normal and proceed
  3. Run the engine until the level rises
  4. Look for leaks at hoses and the radiator, then add coolant to the proper level Correct answer.

Explanation

Low coolant with no puddle may indicate a slow leak or internal loss, so the driver should inspect hoses, clamps, and the radiator before adding coolant. Topping off without finding the cause can lead to overheating on the route.

Question 41Vehicle Inspection

During the pre-trip, the driver hears a hissing sound near a wheel while the parking brake is released. What does this most likely indicate?

  1. A tire that is properly inflated
  2. Normal operation of the cooling fan
  3. An air leak in the brake system that must be repaired Correct answer.
  4. The fuel pump priming the engine

Explanation

Hissing near a wheel with the brake released points to an air leak at a chamber, hose, or fitting. Air leaks can prevent brakes from releasing or applying properly and must be corrected before the bus is driven.

Question 42Vehicle Inspection

The driver inspects the bus's exhaust pipe and finds it is cracked near the manifold. Why is this a serious concern on a school bus?

  1. It increases the tire pressure
  2. It makes the engine run too cool
  3. It causes the turn signals to fail
  4. Exhaust gases could enter the passenger compartment Correct answer.

Explanation

A cracked exhaust can let carbon monoxide and other gases enter the cabin, endangering students and the driver. The exhaust system must be intact and free of leaks before the bus is used.

Question 43Vehicle Inspection

What should the driver check about the bus's battery hold-down bracket during the pre-trip?

  1. That the battery is secured and cannot shift or tip Correct answer.
  2. That the bracket is painted to match the bus
  3. That the battery is removed for the trip
  4. That the battery terminals are left loose for ventilation

Explanation

A battery must be held firmly so it cannot shift, tip, or contact metal, which could cause a short or fire. Loose terminals also cause poor connections and starting problems.

Question 44Vehicle Inspection

The driver checks the bus's service door and finds it does not latch securely when closed. What is the correct action?

  1. Tie the door closed with a rope and proceed
  2. Repair the latch before operating the bus with students Correct answer.
  3. Have a student hold the door during the route
  4. Leave it unlatched since the bus will be moving forward

Explanation

The service door must latch securely to keep students contained and to prevent the door from swinging open in motion. A defective latch is a safety defect that must be repaired before use.

Question 45Vehicle Inspection

During the in-cab check, the driver finds the bus's speedometer and gauges are inoperable. What should the driver do?

  1. Continue the route and watch traffic flow instead
  2. Report the defect and place the bus out of service until repaired Correct answer.
  3. Use a phone app to estimate speed during the route
  4. Cover the gauges so students are not distracted

Explanation

The driver depends on the speedometer and gauges to monitor speed and engine conditions. Inoperable instruments are a defect that must be repaired before the bus carries students.

Question 46Vehicle Inspection

The driver checks the bus's stop lights and finds the brake lights work but the tail lights do not. Which statement best explains why this matters?

  1. Tail lights are used only when the bus is parked
  2. Tail lights make the bus visible to others at night and in low light Correct answer.
  3. Tail lights are needed to start the engine
  4. Tail lights control the interior dome lighting

Explanation

Tail lights mark the rear of the bus for other drivers in darkness, rain, or fog, reducing the chance of a rear-end collision. They are separate from the brake light circuit and must work independently.

Question 47Vehicle Inspection

The driver is inspecting a bus with air brakes and finds the pressure drops below the governor cut-in point but the compressor does not restart. What does this indicate?

  1. Normal operation that needs no attention
  2. A faulty governor or compressor that requires repair Correct answer.
  3. The system is fully charged and should be shut down
  4. The parking brake is improperly adjusted

Explanation

The governor should signal the compressor to resume building pressure when it falls to the cut-in point. Failure to restart means pressure will keep dropping and braking performance will be lost, so the bus must be repaired before use.

Question 48Vehicle Inspection

During the pre-trip, the driver finds the bus's emergency equipment includes a fire extinguisher that shows a discharged gauge. What is the correct action?

  1. Use water from the bus's cooler as a substitute
  2. Shake the extinguisher to restore the gauge reading
  3. Keep it on board and note it in the log for later
  4. Replace or recharge the extinguisher before the bus is used Correct answer.

Explanation

A fire extinguisher must be fully charged and ready for immediate use; a discharged unit provides no protection. The defect must be corrected before the bus operates with students.

Question 49Vehicle Inspection

The driver checks the bus's steering and finds excessive free play at the steering wheel. What is the best interpretation?

  1. Worn steering components may make the bus hard to control and require repair Correct answer.
  2. The steering is within tolerance and can be ignored
  3. The power steering fluid is at the proper level
  4. The tires are correctly inflated

Explanation

Excessive free play indicates worn tie rod ends, a worn steering box, or other looseness that reduces steering precision. This is a safety defect that must be repaired before the bus is driven.

Question 50Vehicle Inspection

The driver inspects the bus's air brake system and finds that with the engine off and brakes released, pressure drops steadily. What does this indicate and what should the driver do?

  1. The brakes are fully applied; release the parking brake
  2. The compressor is overcharging; add more air
  3. A leak in the system; the bus must be repaired before use Correct answer.
  4. Normal cooling of the air; continue the route

Explanation

With the engine off and brakes released, pressure should hold steady; a steady drop reveals a leak in the system. Leaks can reduce braking ability and must be repaired before the bus is placed in service.