B.C. Air Brake Practice Test 2026: Test de práctica 2

Test de práctica 2 de 2 de B.C. Air Brake Practice Test: 35 preguntas más con respuestas y explicaciones.

Vehículo comercial
Columbia Británica
60 preguntas
Revisado el 10 de octubre de 2026

Pregunta 1 de 35
What does the brake pedal (foot valve) do in an air brake system?
- It pumps air into the tanks
- It releases air from the tires
- It switches the compressor on
- It sends air from the tanks to the brake chambers
Ver respuesta
Respuesta: D. It sends air from the tanks to the brake chambers
Pressing the pedal opens the foot valve, which sends air to the brake chambers.
Pregunta 2 de 35
When air enters a brake chamber, what moves?
- A diaphragm pushes the push rod out
- The brake drum starts to spin faster
- The governor cuts out the compressor
- The tank drain valve opens
Ver respuesta
Respuesta: A. A diaphragm pushes the push rod out
Air pressure pushes the diaphragm, which pushes the rod that turns the slack adjuster.
Pregunta 3 de 35
What connects the push rod to the brake camshaft?
- The gladhand
- The foot valve
- The slack adjuster
- The governor
Ver respuesta
Respuesta: C. The slack adjuster
The slack adjuster links the push rod to the camshaft and adds leverage.
Pregunta 4 de 35
Why must water be drained from air tanks?
- Water can freeze and block valves and lines
- Water makes the brakes stronger
- Water cools the engine
- Water is needed for the brakes to work
Ver respuesta
Respuesta: A. Water can freeze and block valves and lines
Water and oil collect in the tanks. In cold weather, water can freeze and stop the system working.
Pregunta 5 de 35
What protects the air tanks from too much pressure?
- The safety valve
- The slack adjuster
- The low air warning
- The brake drum
Ver respuesta
Respuesta: A. The safety valve
If pressure gets too high, the safety valve lets air out.
Pregunta 6 de 35
What must a low air pressure warning do?
- Warn you with a light, buzzer or both when pressure is low
- Stop the engine so the vehicle cannot move
- Fill the air tanks from a reserve supply
- Turn on the hazard lights for other drivers
Ver respuesta
Respuesta: A. Warn you with a light, buzzer or both when pressure is low
The warning tells you pressure is getting low so you can stop safely before the spring brakes apply.
Pregunta 7 de 35
While driving, your low air pressure light and buzzer come on. What is the right action?
- Pull over and stop safely as soon as possible
- Speed up to reach the next town sooner
- Pump the brake pedal to build up air
- Keep driving to the end of your shift
Ver respuesta
Respuesta: A. Pull over and stop safely as soon as possible
Low air means you are losing braking ability. Stop safely and find the cause.
Pregunta 8 de 35
How are spring brakes applied?
- By powerful springs when air pressure is released
- By the driver pulling a cable by hand
- By hydraulic fluid from a master cylinder
- By air pressure pushing on a diaphragm
Ver respuesta
Respuesta: A. By powerful springs when air pressure is released
Spring brakes are held off by air. When air is released, or lost, the springs apply the brakes.
Pregunta 9 de 35
Why are spring brakes used for parking?
- They are the only brakes fitted to the trailer
- They hold mechanically, without needing air in the system
- They are stronger only while the engine runs
- They use less fuel than the service brakes
Ver respuesta
Respuesta: B. They hold mechanically, without needing air in the system
Service brakes rely on air pressure, which can leak away. Spring brakes hold with spring force.
Pregunta 10 de 35
What happens to the spring brakes if the air system loses all its pressure?
- They apply
- They stay exactly as they were
- They switch to hydraulic power
- They release
Ver respuesta
Respuesta: A. They apply
Loss of air pressure lets the springs apply the brakes. This is a safety feature.
Pregunta 11 de 35
Why is a spring brake chamber dangerous to open?
- It contains hot oil under pressure
- Opening it cancels your licence
- It has no parts that can be serviced
- The spring is under great force and could injure you
Ver respuesta
Respuesta: D. The spring is under great force and could injure you
The spring in the chamber is under great force. Only trained people with the right tools should service it.
Pregunta 12 de 35
What is the main advantage of a dual air brake system?
- It works even with no air at all
- It does not need an air compressor
- If one circuit loses air, the other can still apply brakes
- Its brakes never need to be adjusted
Ver respuesta
Respuesta: C. If one circuit loses air, the other can still apply brakes
Two separate circuits mean a failure in one still leaves braking from the other.
Pregunta 13 de 35
On a tractor-trailer, what colour is the gladhand for the service (control) line?
- Red
- Yellow
- Black
- Blue
Ver respuesta
Respuesta: D. Blue
The service line is usually blue, and the supply (emergency) line is red.
Pregunta 14 de 35
What does the tractor protection system do if the trailer breaks away?
- Keeps the tractor's air, while the trailer's spring brakes apply
- It speeds the tractor up to get clear of the trailer
- It turns on the trailer lights to warn others
- It releases all of the tractor's brakes
Ver respuesta
Respuesta: A. Keeps the tractor's air, while the trailer's spring brakes apply
The tractor keeps its air supply, and the trailer brakes apply when its air is lost.
Pregunta 15 de 35
How is brake adjustment checked on S-cam brakes?
- By listening to the brakes while driving slowly
- By checking the tire pressure on each axle
- By measuring push rod stroke with the brakes fully applied
- By feeling how hot each drum is after a trip
Ver respuesta
Respuesta: C. By measuring push rod stroke with the brakes fully applied
Measure how far the push rod moves on a full application. Too much stroke means the brake is out of adjustment.
Pregunta 16 de 35
What does too much push rod stroke mean?
- The brake is working perfectly
- The governor is set too low
- The brake is out of adjustment
- The tank is too full
Ver respuesta
Respuesta: C. The brake is out of adjustment
Excess push rod travel means the brake is out of adjustment and will not give full braking force.
Pregunta 17 de 35
In ICBC's guide, what does brake fade mean?
- The low air warning turning itself off
- Rust building up on the drums
- A loss of braking power when the brakes overheat
- The brake light bulb burning out
Ver respuesta
Respuesta: C. A loss of braking power when the brakes overheat
Overheated brakes lose effectiveness. Keep speed down and use a lower gear and retarder on hills.
Pregunta 18 de 35
How should you apply air brakes for a normal stop?
- Pump the pedal quickly to build air
- Use only the trailer hand valve
- Smoothly and steadily, easing off as you slow
- Press as hard as you can every time
Ver respuesta
Respuesta: C. Smoothly and steadily, easing off as you slow
Smooth, steady pressure stops the vehicle without wasting air or locking wheels.
Pregunta 19 de 35
Why should you avoid fanning (pumping) air brakes?
- It wastes air and lowers the pressure in the system
- It drains fuel from the tank
- It makes the brakes far too strong
- It overheats the engine and compressor
Ver respuesta
Respuesta: A. It wastes air and lowers the pressure in the system
Each pump uses air. Fanning the brakes can drop pressure quickly.
Pregunta 20 de 35
What should you check on the compressor during the air brake inspection?
- The colour and make of the compressor
- That a belt-driven compressor's belt is in good shape and tight
- The fuel level inside the compressor
- The compressor's radio and wiring connection
Ver respuesta
Respuesta: B. That a belt-driven compressor's belt is in good shape and tight
A loose or worn belt can stop the compressor from building air.
Pregunta 21 de 35
During an air brake check, what should happen when you reduce the air pressure by fanning the brakes?
- The engine should stop when pressure falls
- The spring brakes should apply before the warning comes on
- The low air warning should come on before the spring brakes apply
- Nothing should happen until the tanks are empty
Ver respuesta
Respuesta: C. The low air warning should come on before the spring brakes apply
The warning must activate before pressure falls low enough for the spring brakes to apply.
Pregunta 22 de 35
What should you watch on the gauge while the engine builds air?
- That pressure drops while the engine runs
- That the fuel gauge rises with the air pressure
- That the needle stays at zero until you drive
- Steady pressure build-up and cut-out at the right pressure
Ver respuesta
Respuesta: D. Steady pressure build-up and cut-out at the right pressure
Pressure should build at a normal rate and the governor should stop the compressor at the cut-out pressure.
Pregunta 23 de 35
Why do you check for air leaks with the brakes applied?
- Leaks drain air quickly just when you need the brakes
- To test that the horn works on air
- To warm up the engine before driving
- To check the tire pressure on each wheel
Ver respuesta
Respuesta: A. Leaks drain air quickly just when you need the brakes
Leaks reduce the air available for braking, and they get worse when the system is under pressure.
Pregunta 24 de 35
Before testing air brakes on the road, how should you test them at low speed?
- Do not test them on the road at all
- Brake at low speed and check the vehicle stops straight
- Test only the parking brake while moving
- Test them only at highway speed
Ver respuesta
Respuesta: B. Brake at low speed and check the vehicle stops straight
A low-speed test shows if the brakes work and if the vehicle pulls to one side.
Pregunta 25 de 35
What is the purpose of an air dryer?
- To heat the brake drums in winter
- To dry the inside of the cab in wet weather
- To clean the windshield with warm air
- To remove moisture before the air reaches the tanks
Ver respuesta
Respuesta: D. To remove moisture before the air reaches the tanks
An air dryer removes water from the compressed air, which helps prevent freezing and corrosion.
Pregunta 26 de 35
Before you drive, the air gauge shows low pressure. What should you do?
- Drive off and let it build while moving
- Drain the tanks and start again
- Let the pressure build to normal before moving
- Release the spring brakes by hand
Ver respuesta
Respuesta: C. Let the pressure build to normal before moving
Do not move until the air pressure has built up and the low air warning has gone off.
Pregunta 27 de 35
Why must you not apply the service brakes hard while the spring brakes are on?
- Because it is the best way to park on a steep hill
- Because it cools the brakes far too quickly
- Because it uses no air at all from the tanks
- The combined forces can overload and damage brake parts
Ver respuesta
Respuesta: D. The combined forces can overload and damage brake parts
Applying full service air on top of applied spring brakes can over-stress the brake parts.
Pregunta 28 de 35
You park on a hill with an air-brake truck. What should you do?
- Leave the engine running so air keeps building
- Hold the service brake down with a stick
- Use only the trailer hand valve to hold it
- Set the spring brakes and use wheel chocks if needed
Ver respuesta
Respuesta: D. Set the spring brakes and use wheel chocks if needed
Set the parking (spring) brakes and chock the wheels when needed. Never rely on air pressure to hold a parked vehicle.
Pregunta 29 de 35
Where do you apply to take the air brake knowledge test in B.C.?
- At your trucking company
- At a police station
- At a driver licensing office
- At a weigh scale
Ver respuesta
Respuesta: C. At a driver licensing office
Apply at a driver licensing office with your ID and pay the knowledge test fee.
Pregunta 30 de 35
In an emergency, how quickly can a tractor-trailer stop from 100 km/h with good brakes?
- In as little as about 1 second
- In as little as about 7 seconds
- In no less than about 30 seconds
- In no less than about 2 minutes
Ver respuesta
Respuesta: B. In as little as about 7 seconds
A tractor-trailer may stop from 100 km/h in as little as 7 seconds, which takes huge braking force from every brake.
Pregunta 31 de 35
What does the parking brake control knob usually look like?
- A green toggle switch
- A blue, square lever
- A yellow, diamond-shaped push-pull knob
- A red, round push button
Ver respuesta
Respuesta: C. A yellow, diamond-shaped push-pull knob
The parking (spring) brake control is a yellow, diamond-shaped push-pull knob.
Pregunta 32 de 35
In the cab, how can you recognise the trailer supply control?
- A black dial
- A yellow, diamond-shaped knob
- A blue, square knob
- A red, eight-sided push-pull knob
Ver respuesta
Respuesta: D. A red, eight-sided push-pull knob
The trailer supply (tractor protection) control is a red, eight-sided knob.
Pregunta 33 de 35
How does a retarder help the air brakes?
- It adds extra air to the tanks while you drive
- It makes the service brakes apply faster
- It adjusts the slack adjusters automatically
- It slows you without the service brakes, so they stay cool
Ver respuesta
Respuesta: D. It slows you without the service brakes, so they stay cool
Retarders such as engine and exhaust brakes reduce the work, heat and wear on the service brakes.
Pregunta 34 de 35
Which low air warning device is a mechanical arm that drops into view?
- A wig wag
- A slack adjuster
- A governor
- A gladhand
Ver respuesta
Respuesta: A. A wig wag
A wig wag is a mechanical warning arm that drops into view when pressure falls too low.
Pregunta 35 de 35
Which retarder type uses the engine to slow the vehicle?
- An electric driveline retarder
- An engine retarder
- A spring brake
- A trailer hand valve
Ver respuesta
Respuesta: B. An engine retarder
Engine retarders use the engine to slow the vehicle. Others work in the exhaust or the driveline.

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