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ACT Heavy Vehicle Knowledge Test study materials
ACT Heavy Vehicle Knowledge Test study resources

ACT Heavy Vehicle Knowledge Test practice questions

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Question 1Heavy vehicle licence knowledge (ACT)

In the ACT, what is the default speed limit on roads in built-up areas unless signs show otherwise?

  1. 50 km/h Correct answer.
  2. 80 km/h
  3. 60 km/h
  4. 40 km/h

Explanation

The default urban speed limit in the ACT is 50 km/h, which applies to built-up areas unless a sign displays a different limit. Drivers must always obey posted signs where they differ from the default.

Question 2Heavy vehicle licence knowledge (ACT)

What is the maximum blood alcohol concentration permitted for a holder of a full (unrestricted) ACT driver licence?

  1. 0.00
  2. 0.05 Correct answer.
  3. 0.02
  4. 0.08

Explanation

Full licence holders in the ACT must keep their blood alcohol concentration below 0.05. Learner and provisional drivers are subject to a zero alcohol limit.

Question 3Heavy vehicle licence knowledge (ACT)

When must a driver use headlights in the ACT?

  1. Only between sunset and sunrise
  2. Only when it is raining
  3. Whenever visibility is reduced, such as at night, dusk, or in poor weather Correct answer.
  4. Only on unlit rural roads

Explanation

Headlights must be used whenever visibility is reduced, including at night, dawn or dusk, and in rain, fog, or smoke. This ensures the vehicle can be seen and the driver can see the road.

Question 4Heavy vehicle licence knowledge (ACT)

In the ACT, what does a solid white line in the centre of the road mean?

  1. You may cross it to turn into a driveway
  2. The line only applies at night
  3. You must not cross the line to overtake Correct answer.
  4. Overtaking is permitted with care

Explanation

A solid white centre line indicates that crossing it to overtake is prohibited because visibility or road conditions make it unsafe. Drivers must stay on their side of the line.

Question 5Heavy vehicle licence knowledge (ACT)

What is the minimum safe following distance recommended for a heavy vehicle in good conditions in the ACT?

  1. Half a vehicle length
  2. At least three seconds, and more in poor conditions Correct answer.
  3. One second
  4. Two seconds

Explanation

A minimum three-second gap is recommended, and heavy vehicles should allow more because of their greater stopping distance. In wet or poor conditions the gap should be increased further.

Question 6Heavy vehicle licence knowledge (ACT)

A heavy vehicle driver is approaching a roundabout. Who must give way?

  1. Vehicles entering from the left
  2. Vehicles already in the roundabout Correct answer.
  3. Vehicles entering from the right
  4. The largest vehicle

Explanation

Drivers entering a roundabout must give way to vehicles already circulating in it. Heavy vehicle drivers should plan early and signal clearly to avoid cutting off other road users.

Question 7Heavy vehicle licence knowledge (ACT)

What should a heavy vehicle driver do before reversing in a loading area?

  1. Walk around the vehicle to check for hazards and use a spotter if available Correct answer.
  2. Sound the horn briefly and reverse quickly
  3. Ask a passer-by to wave them back without checking
  4. Rely solely on reversing sensors

Explanation

Before reversing, the driver should walk around the vehicle to confirm the path is clear and use a spotter where possible. Reversing sensors and mirrors have blind spots that can hide pedestrians.

Question 8Heavy vehicle licence knowledge (ACT)

In the ACT, when is a driver permitted to use a mobile phone while driving?

  1. When driving below 40 km/h
  2. When using a hands-free device that does not require touching the phone Correct answer.
  3. When stopped at a red light
  4. When sending a quick text message

Explanation

A phone may only be used while driving if it is hands-free and does not require the driver to touch or look at it. Any hand-held use, including texting, is illegal even when stationary at lights.

Question 9Heavy vehicle licence knowledge (ACT)

What does a load projection warning flag indicate on a heavy vehicle?

  1. The load extends beyond the vehicle and needs to be visible to others Correct answer.
  2. The vehicle is over its legal weight
  3. The vehicle is carrying dangerous goods
  4. The brakes are faulty

Explanation

Flags or warning devices are used when a load projects beyond the vehicle so other road users can see the overhang. This helps prevent collisions, especially at night or in poor visibility.

Question 10Heavy vehicle licence knowledge (ACT)

A driver is tired on a long trip. What is the safest action?

  1. Open a window and keep driving
  2. Drink coffee and continue without stopping
  3. Increase speed to arrive sooner
  4. Stop and rest at a safe location Correct answer.

Explanation

Fatigue impairs reaction time and judgement, so the safest response is to stop and rest. Fresh air or caffeine provides only temporary relief and does not replace sleep.

Question 11Heavy vehicle licence knowledge (ACT)

What is the legal requirement for seat belts in a heavy vehicle in the ACT?

  1. Only the driver must wear one
  2. Seat belts are optional in heavy vehicles
  3. Only front-seat occupants must wear one
  4. All occupants must wear seat belts where fitted Correct answer.

Explanation

All occupants of a vehicle must wear a seat belt where one is fitted. The driver is also responsible for ensuring passengers are restrained.

Question 12Heavy vehicle licence knowledge (ACT)

What should a driver do when an emergency vehicle approaches with flashing lights and sirens?

  1. Move to the left and give way safely Correct answer.
  2. Speed up to stay ahead
  3. Stop immediately in the middle of the road
  4. Ignore it if already in a clear lane

Explanation

Drivers must give way to emergency vehicles by moving safely to the left and allowing them to pass. Stopping abruptly in the middle of the road can cause a collision.

Question 13Heavy vehicle licence knowledge (ACT)

In the ACT, what is the maximum speed limit in a school zone during school hours?

  1. 60 km/h
  2. 50 km/h
  3. 40 km/h Correct answer.
  4. 30 km/h

Explanation

School zones in the ACT are signed at 40 km/h during the times shown on the signs. Drivers must slow to this limit whenever the zone is operating to protect children.

Question 14Heavy vehicle licence knowledge (ACT)

What does a load restraint system primarily prevent?

  1. Fuel theft
  2. Engine overheating
  3. Tyre wear
  4. The load shifting or falling off during travel Correct answer.

Explanation

Load restraint systems keep cargo secure so it cannot shift, slide, or fall from the vehicle. An unsecured load can cause serious crashes and injury to other road users.

Question 15Heavy vehicle licence knowledge (ACT)

When parking a heavy vehicle on a hill, what should the driver do?

  1. Leave it in neutral without brakes
  2. Apply the parking brake and use wheel chocks if required Correct answer.
  3. Leave the engine running
  4. Rely only on the gearbox

Explanation

The parking brake must be applied and, where required, wheel chocks used to prevent the vehicle rolling. Leaving it in neutral or relying only on the gearbox is unsafe.

Question 16Heavy vehicle licence knowledge (ACT)

What is the purpose of a pre-start check on a heavy vehicle?

  1. To reduce tyre noise
  2. To clean the windscreen
  3. To improve fuel economy
  4. To identify defects before driving Correct answer.

Explanation

A pre-start check is a systematic inspection to find defects such as brake, tyre, or light faults before the vehicle is driven. This reduces the risk of a breakdown or crash.

Question 17Heavy vehicle licence knowledge (ACT)

What does a stop sign require a driver to do?

  1. Stop completely and give way before proceeding Correct answer.
  2. Stop only if other traffic is present
  3. Slow down and proceed
  4. Sound the horn and continue

Explanation

A stop sign requires a complete stop at the line or sign, followed by giving way to traffic before moving off. Rolling slowly through is not sufficient.

Question 18Heavy vehicle licence knowledge (ACT)

A heavy vehicle driver is turning left at an intersection. Which hazard should they pay particular attention to?

  1. Vehicles behind them
  2. Cyclists and pedestrians on their left side Correct answer.
  3. Road markings on the right
  4. Overhead signs

Explanation

When turning left, the driver must check for cyclists and pedestrians who may be alongside or crossing the road they are entering. Heavy vehicles have significant blind spots that increase this risk.

Question 19Heavy vehicle licence knowledge (ACT)

In the ACT, what is the maximum penalty point system used to track driver behaviour?

  1. A fuel voucher scheme
  2. A vehicle registration discount
  3. A demerit point system that can lead to suspension Correct answer.
  4. A cash reward system

Explanation

The ACT uses a demerit point system in which traffic offences accumulate points that can lead to licence suspension. This encourages safer driving and deters repeat offences.

Question 20Heavy vehicle licence knowledge (ACT)

What should a driver do if they miss their exit on a freeway?

  1. Make a U-turn across the median
  2. Continue to the next exit Correct answer.
  3. Reverse along the shoulder
  4. Stop and wait for a gap

Explanation

If an exit is missed, the driver should continue to the next exit and turn around safely. Reversing or U-turning on a freeway is extremely dangerous and illegal.

Question 21Heavy vehicle licence knowledge (ACT)

What does a yellow traffic light mean?

  1. Give way to the right
  2. Speed up to clear the intersection
  3. Stop if it is safe to do so Correct answer.
  4. Proceed with caution

Explanation

A yellow light warns that the signal is about to turn red, so drivers should stop if it is safe. Accelerating to beat the light increases the risk of a collision.

Question 22Heavy vehicle licence knowledge (ACT)

What is the main risk of overloading a heavy vehicle?

  1. Better fuel economy
  2. Improved braking
  3. Reduced stability and longer stopping distances Correct answer.
  4. Increased tyre life

Explanation

Overloading raises the centre of gravity, reduces stability, and increases stopping distances, making the vehicle harder to control. It also accelerates wear and may breach legal weight limits.

Question 23Heavy vehicle licence knowledge (ACT)

When should a heavy vehicle driver use low gear on a steep descent?

  1. To reduce engine noise
  2. To use engine braking and control speed Correct answer.
  3. To save fuel
  4. Only when the road is wet

Explanation

Selecting a low gear on a steep descent uses engine braking to help control speed and reduces reliance on the footbrake. This helps prevent brake fade and loss of control.

Question 24Heavy vehicle licence knowledge (ACT)

What must a driver do before changing lanes in a heavy vehicle?

  1. Check mirrors and blind spots and signal Correct answer.
  2. Flash headlights
  3. Accelerate sharply
  4. Sound the horn

Explanation

Before changing lanes, a driver must check mirrors and blind spots and signal their intention. Heavy vehicles have large blind spots, so extra care is needed.

Question 25Heavy vehicle licence knowledge (ACT)

What does a broken white line in the centre of the road generally indicate?

  1. The road is one-way
  2. Overtaking is prohibited
  3. Overtaking is permitted when safe Correct answer.
  4. Parking is allowed

Explanation

A broken white centre line indicates that overtaking is permitted when it is safe to do so. Drivers must still check for oncoming traffic and adequate visibility.

Question 26Heavy vehicle licence knowledge (ACT)

In the ACT, what is the general default speed limit on a road in a built-up area where no sign is posted?

  1. 80 km/h
  2. 50 km/h Correct answer.
  3. 40 km/h
  4. 60 km/h

Explanation

ACT roads in built-up areas carry a default limit of 50 km/h unless a sign shows otherwise. Drivers must watch for posted signs that raise or lower the limit.

Question 27Heavy vehicle licence knowledge (ACT)

A heavy vehicle driver intends to tow a trailer that exceeds the permitted towing capacity of the vehicle. What is the correct action?

  1. Ask a passenger to watch the trailer
  2. Do not tow the trailer until the combination is within legal limits Correct answer.
  3. Reduce speed by 20 km/h and proceed
  4. Tow the load only on sealed roads

Explanation

A combination must stay within the rated towing capacity and legal mass limits for the vehicle. Exceeding them makes the vehicle unsafe and unlawful regardless of speed or road surface. The load must be reduced or a suitable vehicle used instead.

Question 28Heavy vehicle licence knowledge (ACT)

What is the purpose of a load restraint system on a heavy vehicle?

  1. To keep the load from moving or falling off during travel Correct answer.
  2. To increase the legal payload of the vehicle
  3. To improve fuel economy on long trips
  4. To reduce engine noise in the cabin

Explanation

Load restraint is designed to hold the load securely so it cannot shift, slide or fall from the vehicle. A shifting load can destabilise the vehicle and endanger other road users.

Question 29Heavy vehicle licence knowledge (ACT)

A driver's heavy vehicle has a tyre with a deep cut exposing the cords. What should the driver do?

  1. Take the vehicle out of service until the tyre is replaced Correct answer.
  2. Reduce speed and complete the trip
  3. Cover the cut and check it at the next stop
  4. Continue if the tyre still holds pressure

Explanation

A tyre with exposed cords is structurally damaged and unsafe to operate. The vehicle should not be driven until the tyre is replaced, because such damage can lead to a blowout.

Question 30Heavy vehicle licence knowledge (ACT)

What does a yellow diamond-shaped sign on an ACT road indicate?

  1. A warning of a hazard or change in road conditions ahead Correct answer.
  2. A toll point on the route
  3. A compulsory stop for heavy vehicles
  4. A parking restriction zone

Explanation

Yellow diamond signs are warning signs that alert drivers to hazards or changed conditions ahead. Drivers should adjust speed and be prepared to respond.

Question 31Heavy vehicle licence knowledge (ACT)

A heavy vehicle is involved in a crash where another person is injured. What is the driver's legal obligation?

  1. Stop, give assistance and report the crash to police Correct answer.
  2. Continue to the destination and report later
  3. Leave the scene if the vehicle is drivable
  4. Exchange details only if the other driver asks

Explanation

After a crash involving injury, the driver must stop, render assistance as far as reasonably possible, and report the incident to police. Failing to stop is a serious offence.

Question 32Heavy vehicle licence knowledge (ACT)

What is the effect of a solid white line separating lanes on a multi-lane road?

  1. Drivers should avoid crossing it except in limited circumstances Correct answer.
  2. It indicates a lane reserved for buses only
  3. Drivers may cross it freely to overtake
  4. It marks the edge of a parking area

Explanation

A solid white lane line generally indicates that lane changing across it should be avoided, though limited exceptions may apply. Drivers should stay within their lane unless it is safe and permitted.

Question 33Heavy vehicle licence knowledge (ACT)

A heavy vehicle driver is following another vehicle in heavy rain at night. How should following distance be adjusted?

  1. Increased to allow for longer stopping distance Correct answer.
  2. Reduced to avoid other vehicles cutting in
  3. Reduced because headlights improve visibility
  4. Kept the same as in dry conditions

Explanation

Wet roads and reduced visibility increase stopping distance, so a larger following gap is needed. Heavy vehicles already need longer stopping distances, which grow further in rain.

Question 34Heavy vehicle licence knowledge (ACT)

What is the main function of an air brake system on a heavy vehicle?

  1. To inflate the tyres while driving
  2. To reduce exhaust emissions
  3. To apply braking force using compressed air Correct answer.
  4. To cool the engine during long climbs

Explanation

Air brake systems use compressed air to actuate the brakes, providing the strong braking force heavy vehicles need. Drivers must ensure air pressure is adequate before moving off.

Question 35Heavy vehicle licence knowledge (ACT)

A driver hears a low-air-pressure warning while driving a heavy vehicle. What should they do?

  1. Continue until the next scheduled service
  2. Switch off the engine while moving
  3. Pump the brake pedal repeatedly to build pressure
  4. Stop safely as soon as possible and investigate Correct answer.

Explanation

Low air pressure compromises braking ability, so the driver should bring the vehicle to a safe stop promptly. The cause should be investigated before continuing.

Question 36Heavy vehicle licence knowledge (ACT)

What does a 'GVM' rating on a heavy vehicle represent?

  1. The maximum speed the vehicle can reach
  2. The weight of the cargo only
  3. The volume of the cargo space
  4. The maximum mass the vehicle is designed to carry including its own weight Correct answer.

Explanation

GVM stands for gross vehicle mass, the maximum total mass of the vehicle including its load and its own weight. Exceeding it is both unsafe and unlawful.

Question 37Heavy vehicle licence knowledge (ACT)

A heavy vehicle driver must enter a work zone where traffic controllers are present. What should the driver do?

  1. Overtake queued vehicles using the shoulder
  2. Sound the horn to clear the way
  3. Maintain the normal speed limit
  4. Follow the directions of traffic controllers and reduced signage Correct answer.

Explanation

In work zones, drivers must obey traffic controllers and any reduced speed signs. Conditions can change quickly, so caution and compliance are essential.

Question 38Heavy vehicle licence knowledge (ACT)

What is the purpose of a heavy vehicle's engine brake or retarder on a long descent?

  1. To improve fuel efficiency when idling
  2. To reduce tyre wear on corners
  3. To increase engine power on the climb
  4. To help control speed without relying only on the footbrake Correct answer.

Explanation

Engine brakes and retarders help hold a steady speed downhill, reducing reliance on the service brakes. This helps prevent brake fade from overheating.

Question 39Heavy vehicle licence knowledge (ACT)

A driver is planning a trip and must calculate whether the load will exceed an axle limit. Which information is most important?

  1. The number of passengers
  2. The axle group mass limits and the load distribution Correct answer.
  3. The age of the tyres
  4. The colour of the vehicle

Explanation

Axle limits apply to each axle group, so the load must be distributed so no group exceeds its limit. This requires knowing the permitted masses and how weight is spread.

Question 40Heavy vehicle licence knowledge (ACT)

What should a driver do when a heavy vehicle's brake warning light stays on after starting?

  1. Disconnect the warning bulb
  2. Investigate the fault before driving Correct answer.
  3. Increase speed to test the brakes
  4. Drive normally and check it at the end of the day

Explanation

A persistent brake warning indicates a possible fault that could affect stopping ability. The driver should not proceed until the issue is checked and resolved.

Question 41Heavy vehicle licence knowledge (ACT)

In the ACT, what does a 'no stopping' sign mean for a heavy vehicle driver?

  1. The vehicle may stop only outside business hours
  2. The vehicle must not stop at any time except in an emergency Correct answer.
  3. The vehicle may stop for up to five minutes
  4. The vehicle may stop briefly to unload

Explanation

A no stopping sign prohibits stopping on that section of road, with limited exceptions such as emergencies or when directed by police. Brief unloading is not permitted.

Question 42Heavy vehicle licence knowledge (ACT)

What is the safest way for a heavy vehicle driver to manage blind spots before a manoeuvre?

  1. Sound the horn and move immediately
  2. Rely only on the interior mirror
  3. Check mirrors and use a head check where possible Correct answer.
  4. Assume other drivers will stay clear

Explanation

Heavy vehicles have large blind spots, so drivers should use all mirrors and a direct head check where feasible before manoeuvring. This reduces the risk of colliding with unseen road users.

Question 43Heavy vehicle licence knowledge (ACT)

A driver is carrying a load of loose gravel. What should be done to prevent spillage onto the road?

  1. Cover or contain the load and check restraint before travel Correct answer.
  2. Drive faster to reduce spillage
  3. Wet the load before departure only
  4. Load the material above the sides of the tray

Explanation

Loose materials must be covered or contained so they cannot spill onto the roadway. The restraint should be checked before travel and during the trip.

Question 44Heavy vehicle licence knowledge (ACT)

What does a red traffic arrow pointing left mean at an intersection?

  1. Drivers must turn left immediately
  2. Left turns are permitted if the road is clear
  3. Drivers must not turn left while the red arrow shows Correct answer.
  4. Left turns are permitted for heavy vehicles only

Explanation

A red arrow applies to the direction it points, so drivers must not turn in that direction while it is displayed. They must wait until a green arrow or other signal permits the turn.

Question 45Heavy vehicle licence knowledge (ACT)

A heavy vehicle driver is required to keep a work diary. What is the main purpose of this record?

  1. To list the vehicle's service history
  2. To note the cargo weight only
  3. To track fuel purchases
  4. To record work and rest times for fatigue management Correct answer.

Explanation

Work diaries record work and rest periods so that fatigue rules can be monitored and enforced. Accurate entries help ensure drivers get adequate rest.

Question 46Heavy vehicle licence knowledge (ACT)

What is the minimum rest requirement concept behind heavy vehicle fatigue laws?

  1. Drivers must take minimum rest breaks within set work periods Correct answer.
  2. Drivers may work unlimited hours if they feel alert
  3. Drivers may skip rest if the trip is short
  4. Drivers only need rest at the end of the week

Explanation

Fatigue laws set maximum work periods and minimum rest breaks to reduce the risk of fatigue-related crashes. Feeling alert does not override the legal limits.

Question 47Heavy vehicle licence knowledge (ACT)

When is a driver required to display 'long vehicle' or rear marker plates on a heavy vehicle?

  1. When the vehicle exceeds the length or mass thresholds set by law Correct answer.
  2. Only on highways
  3. Only at night
  4. Only when carrying dangerous goods

Explanation

Rear marker plates and long vehicle signs are required when a vehicle exceeds specified length or mass thresholds. They warn other road users of the vehicle's size.

Question 48Heavy vehicle licence knowledge (ACT)

A driver notices the steering feels loose and unresponsive. What should they do?

  1. Stop and have the steering system inspected before proceeding Correct answer.
  2. Increase tyre pressure to compensate
  3. Continue and monitor it
  4. Drive only at low speed for the rest of the trip

Explanation

Loose or unresponsive steering indicates a possible mechanical fault that seriously affects control. The vehicle should be stopped and inspected before continuing.

Question 49Heavy vehicle licence knowledge (ACT)

What is the correct action when a heavy vehicle driver is directed by a police officer to stop at a weighbridge?

  1. Stop and comply with the officer's directions Correct answer.
  2. Continue unless a sign also requires stopping
  3. Stop only if the vehicle is overloaded
  4. Radio ahead to confirm the requirement

Explanation

Drivers must obey directions from police and authorised officers, including at weighbridges. Compliance allows mass and safety checks to be carried out.

Question 50Heavy vehicle licence knowledge (ACT)

A heavy vehicle is parked on a road at night in an unlit area. What should the driver ensure?

  1. Only the interior light is on
  2. Parking lights or hazard lights are displayed as required Correct answer.
  3. The vehicle is left completely dark
  4. The vehicle is left with the engine running

Explanation

A parked heavy vehicle in an unlit area at night must be made visible to other road users, typically with parking lights or hazard lights as required. This reduces the risk of collision.