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MO CDL Passenger practice questions

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Question 1Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During a pre-trip inspection of a passenger-carrying vehicle, where should you check the slack adjusters on a vehicle equipped with air brakes?

  1. By pulling each slack adjuster by hand to check for excessive free play
  2. By listening for air leaks at the slack adjuster while the engine idles
  3. By measuring the pushrod travel with the brakes released and applied Correct answer.
  4. By visually inspecting the slack adjuster for a missing cotter pin only

Explanation

The brake pushrod travel measurement is the standard check for slack adjuster adjustment on air-braked vehicles. With the brakes released and then fully applied, the pushrod stroke must fall within the manufacturer's allowable limit. A stroke that is too long indicates the slack adjuster needs adjustment or the brake system needs service before the vehicle is dispatched.

Question 2Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When inspecting the air compressor drive belt on a bus during the pre-trip inspection, what condition should you check for?

  1. The belt is coated with belt dressing to prevent slipping
  2. The belt is loose enough to slip when the engine is accelerated
  3. The belt is routed over all pulleys and has proper tension with no cracks or glazing Correct answer.
  4. The belt is removed so the compressor can be turned by hand

Explanation

The compressor belt must be properly seated on its pulleys and tensioned to the manufacturer's specification. Cracks, glazing, and fraying indicate the belt may fail and leave the air system without a compressor. A loose or missing belt would prevent the compressor from building air pressure.

Question 3Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

While checking the air brake system during the pre-trip inspection, you build pressure to the governor cut-out and then shut off the engine. What should you do next to test for air leaks?

  1. Fan the brake pedal several times and watch for pressure drop
  2. Release the parking brake and watch the pressure gauge
  3. Observe the pressure gauges for a minute with the brakes released and then with the brakes applied Correct answer.
  4. Pump the accelerator to increase engine rpm and watch the gauge

Explanation

With the system at full pressure and the engine off, you watch the gauge for a pressure drop with the brakes released and then with the service brakes applied. A drop beyond the allowable limit indicates an air leak that must be repaired. This static leak test is separate from the low-pressure warning test.

Question 4Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection of a passenger bus, you check the emergency exits. Which condition indicates the exit is ready for service?

  1. The exit opens freely from the inside and the audible alarm sounds when opened Correct answer.
  2. The exit opens only with a special tool kept in the driver's compartment
  3. The exit is locked with a padlock to prevent unauthorized opening
  4. The exit handle is removed to prevent tampering by passengers

Explanation

Emergency exits must open freely from the inside without special tools and must activate the warning device when opened. A locked, blocked, or tool-dependent exit would delay evacuation in an emergency. The pre-trip inspection confirms both operation and warning function.

Question 5Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When inspecting the tires on a passenger-carrying vehicle during the pre-trip inspection, which finding requires the vehicle to be placed out of service?

  1. A tread depth of 6/32 inch on the front steer tires
  2. A cut in the sidewall deep enough to expose the cord Correct answer.
  3. A valve stem cap that is missing on an inner dual tire
  4. A small stone lodged in the tread groove of a rear tire

Explanation

A sidewall cut deep enough to expose the cord is a structural defect that can lead to a blowout and requires the tire to be replaced before dispatch. Tread depth at or above the minimum, a missing valve cap, and a lodged stone are not out-of-service conditions by themselves. Cord exposure compromises the tire's integrity under load.

Question 6Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the steering system. What should you check for when turning the steering wheel with the engine running?

  1. That the steering wheel turns freely and the front wheels respond without excessive free play Correct answer.
  2. That the steering wheel locks in place when turned to the left
  3. That the steering wheel can be turned at least one full revolution before the front wheels move
  4. That the steering wheel requires both hands and excessive force to turn

Explanation

With the engine running and the vehicle stationary, turning the wheel should move the front wheels with only a small amount of free play. Excessive free play or binding indicates a steering defect. The steering wheel should not lock or require excessive force during normal operation.

Question 7Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When checking the lighting system during the pre-trip inspection of a passenger bus, which lights must you verify are working?

  1. Headlights, brake lights, turn signals, clearance lights, and hazard lights Correct answer.
  2. Only the hazard lights and backup lights
  3. Only the headlights and brake lights
  4. Only the interior passenger lights

Explanation

The pre-trip inspection requires checking all exterior lighting, including headlights, brake lights, turn signals, clearance lights, and hazard lights. These lights communicate the vehicle's presence and intentions to other drivers. Missing or inoperative lights are a safety defect that must be corrected before departure.

Question 8Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the parking brake on a passenger bus. What should happen when you apply the parking brake and attempt to move the vehicle?

  1. The vehicle should not move, or should be held securely on a grade Correct answer.
  2. The vehicle should move freely at low speed
  3. The parking brake should release automatically when the accelerator is pressed
  4. The parking brake should only hold the vehicle if the service brakes are also applied

Explanation

The parking brake must hold the vehicle stationary when applied, including on a grade. If the vehicle creeps or rolls with the parking brake set, the brake system needs adjustment or repair. The parking brake is a separate holding system and must function independently of the service brakes.

Question 9Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When inspecting the exhaust system of a passenger bus during the pre-trip inspection, which condition is a defect that must be corrected?

  1. The exhaust system has a loose clamp causing a leak under the passenger compartment Correct answer.
  2. The muffler is free of rust-through holes
  3. The exhaust outlet extends beyond the rear of the vehicle
  4. The exhaust pipe is securely mounted and clear of fuel lines

Explanation

An exhaust leak under the passenger compartment allows carbon monoxide to enter the bus, creating a serious health hazard. The exhaust system must be intact, securely mounted, and routed away from the passenger area. Loose clamps, cracks, and rust-through holes are all defects requiring repair.

Question 10Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the passenger compartment. Which item must be securely stowed or fastened?

  1. The fire extinguisher Correct answer.
  2. The first-aid kit
  3. The spare tire
  4. The driver's logbook

Explanation

The fire extinguisher must be securely mounted so it does not become a projectile and is accessible in an emergency. A loose extinguisher can injure passengers or be unavailable when needed. Other items such as the logbook, spare tire, and first-aid kit also need secure storage, but the extinguisher is the critical safety item specifically checked for secure mounting.

Question 11Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When checking the air brake system during the pre-trip inspection, you notice the low air pressure warning does not activate until the pressure is below 60 psi. What should you do?

  1. Place the vehicle out of service until the warning system is repaired Correct answer.
  2. Adjust the warning buzzer setting yourself
  3. Increase engine rpm to raise pressure and proceed
  4. Continue the trip and note the warning in the log

Explanation

The low air pressure warning must activate before pressure drops below a safe level, typically around 60 psi. If the warning does not function properly, the vehicle must be placed out of service because the driver may not be warned of a dangerous pressure loss. The system must be repaired by qualified maintenance personnel.

Question 12Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the windshield and wipers on a passenger bus. Which condition requires correction before departure?

  1. The washer fluid reservoir is full
  2. The windshield has a small chip outside the driver's line of sight
  3. The wiper blades leave streaks and fail to clear the windshield Correct answer.
  4. The wiper arms are securely attached

Explanation

Wiper blades that streak or fail to clear the windshield impair visibility in rain and must be replaced. A small chip outside the driver's line of sight may be acceptable if it does not obstruct vision. Full washer fluid and secure wiper arms are correct conditions, not defects.

Question 13Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When inspecting the coupling system on a passenger-carrying vehicle that tows a trailer, what should you check?

  1. The coupler is resting on the ball without a latch
  2. The electrical cord is disconnected to prevent battery drain
  3. The trailer is connected only by the safety chains
  4. The safety chains are crossed and attached to the towing vehicle Correct answer.

Explanation

Safety chains should be crossed under the tongue and attached to the towing vehicle to catch the trailer if the coupler fails. The coupler must be fully latched over the ball, and the electrical cord must be connected for lights and brakes. Resting the coupler on the ball without latching is a serious defect.

Question 14Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection of a bus, you check the mirrors. What should you verify?

  1. The mirrors are removed to improve forward visibility
  2. The mirrors are adjusted to show only the front bumper
  3. The mirrors are adjusted to show the sides and rear of the bus Correct answer.
  4. The mirrors are folded in to reduce wind resistance

Explanation

Mirrors must be clean, unbroken, and adjusted to give the driver a clear view of the sides and rear of the bus. Proper adjustment helps the driver monitor passengers, traffic, and clearance. Folded, removed, or improperly aimed mirrors create blind spots and are unsafe.

Question 15Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When checking the suspension system during the pre-trip inspection, which condition indicates a defect?

  1. The U-bolts are tight and free of rust
  2. The air bags are properly inflated
  3. The shock absorbers show normal oil film
  4. A leaf spring has a cracked or broken leaf Correct answer.

Explanation

A cracked or broken leaf spring compromises the vehicle's ability to support its load and can lead to loss of control. The suspension must be inspected for broken leaves, missing parts, and loose U-bolts. Normal oil film on shocks, properly inflated air bags, and tight U-bolts are acceptable conditions.

Question 16Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the brake lights on a passenger bus. How can you verify they are working if you are alone?

  1. Check the brake lights only after the trip begins
  2. Ask a helper to press the brake pedal while you watch the lights
  3. Assume the brake lights work if the fuse is not blown
  4. Use the reflection in a window or a wall to see the brake lights Correct answer.

Explanation

A driver alone can use a reflective surface such as a window or wall to see the brake lights illuminate when the pedal is pressed. This confirms the lights actually work rather than relying on fuse condition alone. Asking a helper is ideal but not always available, and checking after departure is too late.

Question 17Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When inspecting the battery and electrical system during the pre-trip inspection, what should you check?

  1. The battery cables are disconnected to save power
  2. The battery is securely mounted and the terminals are clean and tight Correct answer.
  3. The battery is removed to prevent theft
  4. The battery is covered with a cloth to protect it

Explanation

The battery must be securely mounted to prevent movement and damage, and the terminals must be clean and tight for reliable electrical contact. Loose or corroded connections can cause starting and charging failures. Removing the battery, disconnecting cables, or covering it would disable the vehicle.

Question 18Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the passenger seats and aisles. Which condition must be corrected?

  1. The seats are securely fastened to the floor
  2. An aisle is blocked by a folded wheelchair Correct answer.
  3. The aisle is clear of obstructions
  4. The seat backs are upright and latched

Explanation

The aisle must remain clear so passengers can evacuate quickly in an emergency. A folded wheelchair or any object blocking the aisle is a hazard that must be removed or properly stowed. Securely fastened seats, a clear aisle, and latched seat backs are the desired conditions.

Question 19Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When checking the air brake system during the pre-trip inspection, you perform a test to confirm the spring brakes apply automatically when air pressure is lost. What should you observe?

  1. The service brakes release and the vehicle rolls
  2. The air compressor runs continuously to maintain pressure
  3. The parking brake valve pops out and the vehicle is held Correct answer.
  4. The low air warning sounds but the brakes do not apply

Explanation

When air pressure drops below a safe level, the spring brakes should apply automatically and the parking brake valve should pop out. This fail-safe design stops the vehicle if air pressure is lost. The test confirms the spring brake system will function in an emergency.

Question 20Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the frame and undercarriage of a passenger bus. Which finding is a defect?

  1. Light surface rust on the frame
  2. A securely mounted fuel tank
  3. A crack in the frame rail near a suspension mount Correct answer.
  4. Exhaust hangers in good condition

Explanation

A crack in a frame rail weakens the vehicle's structure and can lead to catastrophic failure, especially near suspension or steering mounts. The frame must be inspected for cracks, broken welds, and loose fasteners. Light surface rust, a secure fuel tank, and good exhaust hangers are acceptable.

Question 21Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When inspecting the tires on a passenger bus during the pre-trip inspection, you check the dual tires. What should you verify?

  1. There is adequate clearance between the dual tires and no debris lodged between them Correct answer.
  2. The inner dual tire is flat and the outer tire carries the load
  3. The dual tires are touching each other to save space
  4. The valve stems are removed to prevent damage

Explanation

Dual tires must have adequate clearance so they do not rub together, which can cause overheating and blowouts. Debris lodged between duals can damage the sidewalls. Touching tires, a flat inner tire, or missing valve stems are all defects.

Question 22Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the horn on a passenger bus. What is the correct procedure?

  1. Sound the horn and confirm it is loud enough to be heard by other drivers Correct answer.
  2. Test the horn only after the vehicle is moving
  3. Press the horn only while the engine is off
  4. Remove the horn fuse to prevent accidental honking

Explanation

The horn must be tested during the pre-trip inspection to confirm it works and is audible. A functioning horn is a safety device used to warn others. Testing with the engine off may not work if the horn requires electrical power, and testing after moving is too late.

Question 23Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When checking the air brake system during the pre-trip inspection, you perform a test to ensure the service brakes release properly. What should you observe?

  1. The brake chambers do not return to the released position
  2. The vehicle remains braked after releasing the pedal
  3. The low air warning activates when the pedal is released
  4. The vehicle rolls freely when the brake pedal is released Correct answer.

Explanation

After applying and releasing the service brakes, the vehicle should roll freely, indicating the brakes have fully released. If the vehicle remains braked, a brake may be dragging, which can cause overheating and loss of braking. The low air warning should not activate during a normal release.

Question 24Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the passenger entry door on a bus. Which condition is acceptable?

  1. The door opens and closes smoothly and the warning device operates Correct answer.
  2. The door is tied open with a rope
  3. The door handle is missing
  4. The door glass is cracked and taped

Explanation

The entry door must operate smoothly and the warning device must function to alert the driver when the door is open. A door tied open, cracked glass, or a missing handle are all defects. The door is a critical safety and passenger-control component.

Question 25Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When inspecting the fuel system during the pre-trip inspection of a passenger bus, which condition requires attention?

  1. The fuel tank is free of leaks
  2. The fuel gauge shows a full tank
  3. The fuel tank is securely mounted and the cap is tight
  4. A fuel line is chafed and seeping fuel Correct answer.

Explanation

A chafed fuel line that is seeping fuel is a fire hazard and must be repaired before the vehicle is used. The fuel system must be inspected for leaks, secure mounting, and tight caps. A full tank and a leak-free tank are acceptable conditions.

Question 26Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During a pre-trip inspection of a passenger bus, you must verify the emergency exit(s). Which condition confirms an emergency exit is acceptable for service?

  1. The exit handle is removed so passengers cannot open it in motion
  2. The exit glass is covered by a route advertisement decal
  3. The exit is locked from the outside to prevent unauthorized entry
  4. The exit opens freely from the inside and the warning device sounds when it is opened Correct answer.

Explanation

Emergency exits must open freely from the inside without special tools, and on most buses a warning buzzer or light must activate when the exit is opened. This confirms passengers can escape and that the driver is alerted if an exit is unlatched. Locking or blocking the exit defeats its purpose.

Question 27Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, how should you check the engine oil level on a passenger bus?

  1. By watching the oil pressure gauge only, without using the dipstick
  2. With the engine off and the bus level, pull the dipstick, wipe it, reinsert it fully, and read the level Correct answer.
  3. Immediately after shutdown while oil is still draining down
  4. With the engine running at high idle so oil is circulating

Explanation

Oil level is checked with the engine off on level ground; the dipstick is wiped, fully reinserted, and then read so the mark is accurate. Checking while running or right after shutdown gives a false reading because oil has not drained back to the pan. The gauge shows pressure, not quantity.

Question 28Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When checking the coolant level during the pre-trip inspection of a bus, what is the correct practice?

  1. Fill the system to the top of the filler neck every morning regardless of the mark
  2. Check the level at the sight glass or overflow reservoir with the engine cool, and never open a hot pressurized cap Correct answer.
  3. Remove the radiator cap while the engine is hot to check the level directly
  4. Rely on the temperature gauge alone and skip the visual check

Explanation

Coolant is checked cold at the sight glass or reservoir against the marked level. Opening a hot pressurized cooling system can release scalding coolant and cause serious burns. The temperature gauge does not confirm the coolant quantity.

Question 29Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the power steering fluid. Which observation indicates a defect requiring correction?

  1. The reservoir cap is tight and the vent is clear
  2. The fluid level is below the add mark or the reservoir is leaking Correct answer.
  3. The fluid is at the full mark on the reservoir dipstick
  4. The fluid is a clear reddish color

Explanation

Power steering fluid must be at or above the add mark, and the system must not leak. Low fluid or a visible leak can cause loss of steering assist while driving, which is dangerous in a bus. Fluid color and a secure cap are normal findings, not defects.

Question 30Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

When inspecting the wheels and rims during the pre-trip inspection of a bus, which finding is a defect?

  1. A small amount of road dust on the rim surface
  2. Rust streaks around the lug nuts that show the nuts have been recently disturbed
  3. Rust streaks that indicate a loose or shifting wheel Correct answer.
  4. Valve stems that point outward and are capped

Explanation

Rust streaks or shiny wear around lug nuts and studs can show the wheel has been shifting or the nuts are loose, which is a defect. Ordinary road dust and capped valve stems are normal. Streaking that indicates recent disturbance must be investigated, not ignored.

Question 31Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the slack adjusters on a bus with air brakes. What should you verify?

  1. That the slack adjuster is greased with the engine running at high idle
  2. That the pushrod travel exceeds the adjustment limit on every chamber
  3. That the slack adjuster is welded to the pushrod for security
  4. That the pushrod travel is within the limit and the adjuster is not broken or disconnected Correct answer.

Explanation

Slack adjusters must be intact and the pushrod travel must be within the limit for the chamber type. Excessive pushrod travel means the brakes are out of adjustment and stopping distance increases. A broken or disconnected adjuster disables that brake.

Question 32Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the air compressor and air system for leaks. What is the correct procedure?

  1. Build air pressure to the governor cut-out, shut off the engine, and watch the gauge for a pressure drop Correct answer.
  2. Drain all air from the tanks and listen for the compressor to start
  3. Release the parking brake and watch for the bus to roll
  4. Leave the engine running and listen for the governor to cut in

Explanation

With the system at full pressure and the engine off, a gauge drop over time indicates an air leak that must be found and repaired. The acceptable leak rate is small; any steady loss means the bus is not safe to operate. Draining all air or releasing the park brake does not test for leaks.

Question 33Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection of a passenger bus, you check the windshield washer fluid and spray. Which result is acceptable?

  1. The washer reservoir is empty but the wipers still move
  2. The washer nozzle is clogged and no fluid reaches the glass
  3. The washer sprays onto the windshield and the wipers clear it in the wipe pattern Correct answer.
  4. The washer sprays a weak stream that barely reaches the glass

Explanation

The washer must deliver fluid to the windshield and the wipers must spread and clear it across the wipe pattern. A clogged nozzle or empty reservoir leaves the driver unable to clear road spray, which is a defect. Visibility equipment must work before the trip begins.

Question 34Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the passenger compartment lighting and stepwell. Which condition must be corrected before departure?

  1. A burned-out stepwell light that leaves the entry step unlit Correct answer.
  2. A stepwell light that comes on with the headlights
  3. Interior lights that illuminate when the door opens
  4. An entry step with a clean, dry tread surface

Explanation

The stepwell light must illuminate the entry so passengers can see the step in darkness; a burned-out bulb is a defect. Lights that operate with the door or headlights and a clean, dry step are correct conditions. Passengers are injured on unlit steps.

Question 35Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection of a bus, you check the stop arm and crossing gate (if equipped). What should you verify?

  1. That the crossing gate lowers only after the bus begins moving
  2. That the stop arm extends fully and the red lights flash when deployed Correct answer.
  3. That the stop arm stays retracted at all times, even when students are present
  4. That the red lights stay on continuously while the bus is in motion

Explanation

Where a stop arm is fitted, it must extend fully and the warning lights must flash when deployed so traffic stops. A gate that deploys only after the bus moves or lights that stay on in motion indicate a control defect. The arm must retract fully when stowed.

Question 36Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the air brake low pressure warning device. At what pressure must the warning activate?

  1. Only after the pressure falls below 10 psi
  2. Before the pressure drops below 60 psi Correct answer.
  3. At the governor cut-out pressure
  4. When the parking brake is released

Explanation

The low air pressure warning must activate before pressure falls below 60 psi so the driver has time to stop safely. A warning that comes on only at very low pressure or not until cut-out gives no useful margin. The warning is independent of the parking brake.

Question 37Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection of a bus, you check the safety equipment. Which set of items must be on board and in good condition?

  1. A spare tire, a jack, and a lug wrench
  2. A tow chain and a spare battery
  3. A fire axe and a spare windshield
  4. Fire extinguisher, emergency triangles or reflectors, and a first aid kit where required Correct answer.

Explanation

Buses carry a charged fire extinguisher, warning triangles or reflectors, and a first aid kit where the rules require one. Each must be present, secured, and in working condition. Spare tires and tow gear are not the required safety equipment for a passenger bus.

Question 38Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the fire extinguisher on a passenger bus. Which condition is acceptable?

  1. The safety pin is missing and the handle is taped down
  2. The extinguisher is loose in a storage bin so it can be reached quickly
  3. The gauge needle rests in the red recharge zone
  4. The gauge needle is in the green operating range and the extinguisher is securely mounted Correct answer.

Explanation

A fire extinguisher must show a charged gauge in the operating range and be securely mounted so it does not become a projectile. A red gauge means it needs recharge, and a loose or tampered unit may not work. The pin must be in place.

Question 39Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the rear of the bus. Which condition requires correction?

  1. Reflectors that are clean and unbroken
  2. A rear bumper that is cracked and loosely attached Correct answer.
  3. Mud flaps that hang straight and clear the tires
  4. A rear emergency door that opens from the inside with the warning sounding

Explanation

A cracked, loose bumper can separate and strike other vehicles or pedestrians, so it must be repaired. Straight mud flaps, a working rear emergency door with its warning, and clean reflectors are all correct conditions. Structural attachments must be secure.

Question 40Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the brake drums and linings on a bus. Which finding is a defect?

  1. Drums that are cool to the touch before the trip
  2. A light film of dust on the drum exterior
  3. Linings with visible thickness above the wear limit
  4. Oil or grease contamination on the lining surface Correct answer.

Explanation

Oil or grease on the linings reduces friction and can cause brake pull or failure, so it must be corrected. Light dust, cool drums before operation, and linings above the wear limit are normal. Contaminated linings must be replaced or cleaned.

Question 41Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the fifth wheel on a bus that tows a trailer. Which condition is a defect?

  1. The locking jaws are open and the release handle is pulled out Correct answer.
  2. The mounting bolts are tight and the jaws are closed around the kingpin
  3. The fifth wheel plate is greased
  4. The safety latch is engaged over the release handle

Explanation

The locking jaws must be closed around the kingpin with the safety latch engaged, and the handle must be in. Open jaws mean the trailer can separate from the tractor. Tight bolts, grease, and an engaged latch are correct conditions.

Question 42Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection of a bus, you check the headlights, taillights, brake lights, and turn signals. How should you confirm the brake lights work when you are alone?

  1. Turn on the hazard lights and treat that as proof
  2. Ask a passenger to sit in the driver's seat while you stay inside
  3. Assume they work because the taillights come on
  4. Watch the reflection on a wall or use a mirror or reflective surface behind the bus Correct answer.

Explanation

When no helper is available, use a wall, window, or mirror to see the reflection of the brake lights as you press the pedal. Taillights and hazard lights are separate circuits and do not prove the brake lights work. Confirming each circuit is part of the lighting check.

Question 43Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection of a bus, you check the entry door and its controls. Which condition is acceptable?

  1. The door control sticks and requires two attempts to close
  2. The door opens and closes smoothly and the warning buzzer sounds while it is open Correct answer.
  3. The door closes only when the engine is at high idle
  4. The door edge has a torn rubber seal that lets in water

Explanation

The entry door must open and close smoothly and the warning device must sound while it is open so the driver knows passengers may be boarding or exiting. A torn seal or a sticking control is a defect. The door must not depend on high idle to close.

Question 44Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the bus heater and defroster. Which result is acceptable?

  1. The defroster blows only cold air on the windshield
  2. The heater fan runs but no air comes out of the vents
  3. The defroster works only when the bus is moving
  4. The defroster blows warm air that clears the windshield and the heater warms the passenger area Correct answer.

Explanation

The defroster must deliver warm air to clear the windshield, and the heater must warm the passenger compartment. Cold defroster air, no airflow, or operation only in motion means the system is defective. Passenger comfort and driver visibility depend on it.

Question 45Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the bus's mirrors and their brackets. Which condition requires correction?

  1. A convex mirror that shows a wider view on the right side
  2. A mirror bracket that is cracked or loose so the mirror vibrates Correct answer.
  3. Mirrors adjusted so the driver can see both sides of the bus
  4. Mirror glass that is clean and free of cracks

Explanation

A cracked or loose bracket lets the mirror vibrate or fall, so the driver loses the view needed to check blind spots. Mirrors correctly adjusted, a convex mirror for a wider view, and clean glass are all acceptable. Mirror security is part of the inspection.

Question 46Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection of a bus, you check the fuel system. Which finding requires correction?

  1. Fuel lines that are dry and free of seepage
  2. A fuel tank cap that is missing or does not seal Correct answer.
  3. A tank that is securely mounted with tight straps
  4. A fuel gauge that reads above empty

Explanation

A missing or non-sealing fuel cap allows fuel to spill and vapors to escape, creating a fire hazard, so it must be corrected. Dry lines, a gauge above empty, and a securely strapped tank are acceptable conditions. Fuel leaks and open tanks are serious defects.

Question 47Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the bus's seat belts where fitted. Which condition must be corrected?

  1. A belt anchored securely to the floor
  2. A buckle that latches with a firm click
  3. A belt that retracts fully when released
  4. A belt that is frayed or has a broken buckle Correct answer.

Explanation

A frayed belt or a buckle that will not latch can fail in a crash and must be replaced. Belts that retract, buckles that click firmly, and secure anchors are correct. Each belt position must be checked before passengers use it.

Question 48Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the air brake system's application and release. What should happen when you apply the service brake and then release it?

  1. The brakes apply but stay engaged after the pedal is released
  2. The brakes apply only when the parking brake is set
  3. The brakes apply smoothly and release fully with no dragging or delay Correct answer.
  4. The brakes release only after the engine is shut off

Explanation

Service brakes must apply smoothly and release completely so the bus does not drag or overheat the brakes. Brakes that stay engaged or release only after shutdown indicate a valve or return-spring defect. The test confirms both application and full release.

Question 49Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection of a bus, you check the drive shaft and universal joints. Which finding is a defect?

  1. A drive shaft that is clean and free of grease buildup
  2. A universal joint that is loose or has missing cap bolts Correct answer.
  3. A joint fitting that is properly lubricated
  4. A shaft that turns without vibration during a slow roll

Explanation

A loose universal joint or missing cap bolts can let the drive shaft separate, causing loss of control, so it must be repaired. A clean shaft, lubricated fittings, and smooth rotation are acceptable. Drive line security is critical on a passenger bus.

Question 50Vehicle Inspection (pre-trip inspection) - CDL Manual Section 11M

During the pre-trip inspection, you check the bus's air tanks. What should you do with the drain valves?

  1. Drain the tanks to remove moisture and confirm the valves close and do not leak Correct answer.
  2. Tighten the valves so they cannot be opened
  3. Drain the tanks only when the low pressure warning sounds
  4. Leave the valves open so moisture can escape while driving

Explanation

Air tank drains remove condensed moisture that can freeze or corrode the system, and the valves must close tightly afterward. Valves left open will not build pressure, and valves that cannot open prevent draining. Draining is a routine pre-trip step.