Iowa Passenger CDL Practice Test

This is a free 20-question practice test for the Passenger portion of the Iowa Commercial Driver's License knowledge exam. Questions are pulled from a pool of 58 drawn from the AAMVA CDL Manual, which is the source document the Iowa Department of Transportation Motor Vehicle Division uses to write its actual exam.

How it works: Click an answer. The correct choice highlights in green, and you'll see a short explanation. Aim for 85% or better before you sit for the real test in Iowa.

Question 1 of 20

The "standee line" on a bus marks:

Where standees may not pass while the bus is in motion (typically 2 feet behind the driver)
The middle aisle
The rear emergency exit
The fuel-fill location

Correct. On buses with a standee line, passengers may not stand forward of the line while the bus is moving. The line keeps standees clear of the driver and exit doors.

Question 2 of 20

A bus driver should:

Refuse boarding to obviously intoxicated passengers if they pose a danger
Carry any passenger
Carry only adults
Only carry seated passengers

Correct. Carriers may refuse boarding for safety reasons (intoxication, weapons, threatening behavior). Document and report such refusals.

Question 3 of 20

Which of the following is part of the bus pre-trip inspection?

Passenger seat condition, emergency exits, signaling devices, kneeling mechanism, wheelchair lift if equipped
Only the engine
Only the brakes
Only the lights

Correct. Bus inspection includes all standard items plus passenger-area items: seats, emergency exits, signaling devices, kneeling/lift equipment, fire extinguisher.

Question 4 of 20

You discover an emergency exit that does not function. You should:

Carry passengers anyway
Place the bus out of service until the exit is repaired
Tape it shut
Ignore it

Correct. A non-functional emergency exit puts passengers at risk. The bus is out of service until repaired.

Question 5 of 20

You may NOT carry which of the following on a passenger bus?

Small-arms ammunition, hospital supplies in emergency
Class 2.3 (poison gas) or Class 7 (radioactive) above small quantities, tear gas, explosives other than small arms ammunition
Driver's personal luggage
Mail

Correct. Buses cannot carry Class 2.3 poison gases, most Class 7 radioactive materials, tear gas, or most Class 1 explosives. Small-arms ammunition and certain emergency shipments may be allowed.

Question 6 of 20

Bus brake systems require:

The same federal pre-trip air-system check as other commercial vehicles, with attention to bus-specific items (door interlocks, retarders if equipped)
No special check
Hydraulic checks only
Only the parking brake

Correct. Standard air-system check applies. Bus-specific: door safety interlock (door open = vehicle can't move), retarder/exhaust brake operation if equipped.

Question 7 of 20

When stopping at a railroad crossing, the bus must stop:

On the rails
Between 15 and 50 feet from the nearest rail
Anywhere within 100 feet
Only if a train is heard

Correct. Stop 15 to 50 feet from the nearest rail. Look both ways and listen before proceeding.

Question 8 of 20

When approaching a school bus on the same side of the road with red lights flashing:

Stop
Pass slowly
Pass quickly
Honk the horn

Correct. Drivers (including bus drivers) approaching a school bus loading or unloading children must stop until red lights are off and the bus moves.

Question 9 of 20

Passenger fatalities are most often caused by:

Single-vehicle rollovers and collisions; speed and seat belts (where required) are common factors
Mechanical failure
Bad weather only
Cargo

Correct. Single-vehicle rollover and head-on/angle collisions account for most passenger fatalities. Speed control and where applicable, seatbelt use, reduce risk.

Question 10 of 20

A bus driver must never:

Refuse to allow standees forward of the standee line
Use turn signals
Honk the horn
Wear a uniform

Correct. You should always enforce the standee line and prohibit standing or sitting in stairwells where they could be ejected in an emergency stop.

Question 11 of 20

A "passenger vehicle" requiring a P endorsement is generally:

Any commercial vehicle
A vehicle designed to transport 16 or more people, including the driver
A vehicle that carries cargo
A school bus only

Correct. The P endorsement is required for any commercial motor vehicle designed to carry 16 or more passengers including the driver.

Question 12 of 20

Carry-on baggage on a bus may be:

Stored anywhere
Stored in overhead racks or under seats — never blocking aisles or emergency exits
Stored in the aisle
Held in your lap

Correct. Carry-on must not block the aisle, the emergency exit, or the doorway. Use overhead racks or under-seat space.

Question 13 of 20

When backing a bus, you should:

Sound the horn before moving and use a helper outside the bus when available
Back without warning
Back only at night
Back only with passengers

Correct. Sound the horn before backing. Use a helper to guide whenever possible — bus blind spots are large.

Question 14 of 20

When a passenger is disorderly:

Pull over at a safe location, follow the carrier's procedure, request assistance from law enforcement if needed
Argue with them
Speed up
Drive faster

Correct. Driver safety first: pull off safely, follow company policy, request help from authorities if the situation warrants.

Question 15 of 20

Looking out for passengers boarding through the front door:

Watch for elderly, mobility-limited passengers and those with strollers; offer the kneeling feature if equipped
Rush them
Only watch for adults
Ignore them

Correct. Use the kneeling mechanism, lift, or ramp as needed. Allow time for safe boarding.

Question 16 of 20

On a bus with a wheelchair lift, you should:

Verify the lift is operating and stowed correctly during pre-trip
Ignore it
Operate it only after passengers complain
Skip the lift

Correct. Test lift operation during pre-trip; verify it stows correctly so it does not interfere with door operation or hit cars during the route.

Question 17 of 20

A passenger vehicle drove with people standing forward of the standee line. This is:

Acceptable
Prohibited — standees may not be forward of the line while the vehicle is in motion
Required
Encouraged

Correct. Standees forward of the line are at risk in emergency stops or sudden braking. Enforce the line.

Question 18 of 20

Buses must stop at every railroad crossing:

Yes, with limited exceptions (industrial switching tracks in city traffic, abandoned tracks, streetcar tracks)
No, never
Only at night
Only if a train is in sight

Correct. Buses, school buses, and placarded hazmat vehicles must stop at every railroad crossing 15 to 50 feet from the nearest rail, with narrow exceptions.

Question 19 of 20

Driving a bus on slick roads requires:

Lower speed, longer following distance, and gentler steering and braking
Higher speed
Same speed as a car
Only the trailer brake

Correct. Reduce speed, increase following distance, and treat all inputs as if a passenger is standing — they may be.

Question 20 of 20

When approaching a school bus that has its red flashing lights on:

Stop and wait until the lights are turned off and the school bus moves
Pass on the left
Pass on the right
Continue at speed

Correct. When a school bus is loading or unloading children with red flashers on, all approaching vehicles (with limited exceptions for divided highways) must stop.

About the Iowa Passenger exam

Most states administer 20 Passenger questions and require 80% to pass. The exam covers passenger safety, vehicle inspection, loading and unloading, prohibited cargo, emergency exits, and conduct expected of a passenger-vehicle operator. A separate skills test in a representative passenger vehicle is also required.

The Iowa Department of Transportation Motor Vehicle Division follows the federal CDL standards established by FMCSA. To earn the Passenger credential, you must answer at least 80% of the questions correctly. Many candidates score lower the first time because the test pulls from a large pool — refreshing this page will give you a different mix of questions, drawn from the same authoritative source.

Want more practice? Try the full Passenger question bank or browse all Iowa CDL practice tests.