Ontario · CDL Study Guide · Part 7 · Chapters 63–74

Left and right turns +11Ontario · CDL · English

47 topics · Updated 2026-09-17

63.Left and right turns

📋

Turn Approach

general

When approaching a turn, monitor surrounding traffic, do a visual search of the intersection, select the correct lane (with a lane change if needed), signal early, slow gradually, select an appropriate gear, and plan the correct pathway for entering and exiting.

Key Rules
  • Conduct a visual search for vehicles, pedestrians and objects and correctly select the lane
  • Activate turn signals on approach as soon as appropriate
  • Select a gear appropriate for speed and load that keeps the engine in its normal RPM range
  • Plan the correct pathway for entering and exiting the intersection
📋

Stopping at a Turn

general

If stopping, execute a smooth full stop without rolling, stop in the proper legal position with reasonable gap to see the area ahead, keep wheels straight while waiting, and check left, ahead, right and behind before entering.

Key Rules
  • Complete a smooth full stop without rolling backward or forward
  • Stop in the proper legal position with reasonable space to the vehicle ahead
  • Keep the wheels straight while waiting to turn
  • Before entering, check to the left, ahead, to the right and behind to ensure the way is clear
📋

Executing the Turn

general

During the turn, monitor traffic ahead, beside and in mirrors, maintain a two-handed grip, minimize gear changes, complete the turn at an appropriate speed, respond correctly to right-of-way, and follow the path appropriate for the vehicle's size to avoid running too wide or short.

Key Rules
  • Maintain a two-handed grip and minimize/avoid unnecessary gear changes during the crossing
  • Recognize and respond correctly to right-of-way obligations; failure to take own right-of-way impedes traffic
  • Follow the path appropriate for your vehicle size and length (not too wide or short)
📋

Completing the Turn

general

After turning, make regular traffic checks, turn into the lane corresponding to the one you started in, choose a lane free of obstructions, cancel signals to avoid confusing others, and accelerate smoothly. After a left turn, select the lane providing safest unimpeded travel for through traffic.

Key Rules
  • Turn into the lane that corresponds to the lane you were in at the start of the turn
  • Cancel signals after the turn so other drivers are not confused
  • Accelerate smoothly and pick up speed so as not to delay other traffic
  • After a left turn, move to the lane providing the safest unimpeded travel

64.Annual Inspection Certificate

📋

Annual Inspection Requirements

general

Operators must have each vehicle and trailer inspected annually by a licensed motor-vehicle inspection mechanic per NSC Standard 11, Part B. A compliant vehicle receives an annual inspection certificate, record and sticker (decal) placed on the lower left windshield/cab or front left of a trailer. Drivers must check the decal date during daily inspection to ensure validity.

Key Rules
  • Vehicles and trailers must be inspected annually by a licensed mechanic per NSC Standard 11 Part B
  • The inspection decal is placed on the outside lower left corner of windshield/cab or front left of trailer
  • Drivers must check the decal date during daily inspection to ensure validity

65.Daily Trip Inspection — Classes A and D

📋

Daily Inspection Legal Requirement

general

A driver may not drive a truck unless they or another person conducted a Schedule 1 inspection and completed an inspection report within the previous 24 hours. The inspection is a legal requirement of the HTA and must be completed every 24-hour period, with the vehicle monitored throughout the trip. Drivers must carry both the current inspection report and the inspection schedule (electronic permitted).

Key Rules
  • A Schedule 1 inspection and report must be completed within the previous 24 hours before driving
  • Drivers must complete a vehicle inspection every 24-hour period
  • Drivers must carry both the current inspection report and the inspection schedule
📋

Major and Minor Defects

general

The inspection schedule divides defects into major and minor. For a minor defect, the driver must record it on the report and report it to the operator. Drivers are NOT permitted to drive a vehicle with a major defect. Major defects must be repaired before operating the vehicle again.

Key Rules
  • Minor defects must be recorded on the report and reported to the operator
  • Drivers are not permitted to drive a vehicle with a major defect
  • Major defects must be repaired before operating the vehicle again
🛑

Common Out-of-Service Reasons

airbrakes

The most common reason for taking a commercial vehicle out of service is out-of-adjustment air brakes. Other reasons include insecure loads, defective lights or tires, and broken springs. Out-of-adjustment air brakes may result in vehicle detention and possible CVOR cancellation/suspension. You cannot adjust your own air brakes unless you completed an approved air brake adjustment course or are a certified mechanic.

Key Rules
  • Out-of-adjustment air brakes are the most common out-of-service reason
  • You cannot adjust your own air brakes unless you completed an approved course or are a certified mechanic
  • Out-of-adjustment air brakes can result in detention and CVOR cancellation/suspension
📋

Required Daily Inspection Items

general

The daily inspection must include (per O.Reg 199/07): air brake system (if equipped), cab, cargo securement, coupling devices, dangerous goods, driver controls, driver seat, electric brake system, emergency equipment, exhaust system, frame and cargo body, fuel system, glass and mirrors, heater/defroster, horn, hydraulic brake system, lamps and reflectors, steering, suspension, tires, wheels/hub/fasteners, and windshield wiper/washer.

Key Rules
  • Daily inspection must include air brake system (if equipped), cab, coupling devices and steering
  • Must include tires, wheels/hub/fasteners, lamps and reflectors, and suspension system
  • Must include glass and mirrors, horn, exhaust system and windshield wiper/washer

66.Emergency Vehicles

📋

Reacting to an Approaching Emergency Vehicle

general

Emergency vehicles use flashing red (or red and blue) lights, sirens/bells, or alternating white high-beam flashes. When one approaches from either direction, you must immediately slow down, move right and stop.

Key Rules
  • When you see or hear an approaching emergency vehicle from either direction, immediately slow down, move as far to the right as you can and stop
  • It is illegal to follow within 150 metres of a fire vehicle or ambulance responding to a call in the same direction
  • Do not drive on or block the shoulder on freeways as emergency vehicles may use it
  • Yield the right-of-way to volunteer responders displaying a flashing green light
📋

Reacting to a Stopped Emergency Vehicle or Tow Truck

general

When you see a stopped emergency vehicle with red/red and blue lights or a tow truck with amber lights flashing in your direction, you must slow down and pass with caution, moving over if possible.

Key Rules
  • Slow down and pass with caution when passing a stopped emergency vehicle or tow truck with lights flashing
  • If the road has two or more lanes, move over to allow one lane clearance if it can be done safely
  • Failing to follow can result in conviction, demerit points, licence suspension up to two years, and fines of $400-$2,000 (first) or $1,000-$4,000 (subsequent)

67.Daily inspection test

📋

Daily inspection test structure

general

The daily inspection test determines your knowledge and skills for safe operation and to identify minor or major defects per O. Reg. 199/07. It is performed in order: exterior inspection, in-cab check, interior inspection. Exterior/interior items are randomly selected from Schedule 1; all in-cab items must be inspected, using Schedule 1 as a reference. The exterior inspection is done with the parking brake engaged and wheels chocked.

Key Rules
  • The daily inspection is performed in order: exterior, in-cab, then interior
  • Perform the exterior inspection with parking brake engaged and wheels chocked
  • You may use Schedule 1 as a reference during the test
🛑

Air pressure build-up and leak testing

airbrakes

A minor defect exists when air pressure takes longer than two minutes to build from 85 to 100 psi (test at 600-900 RPM). Any audible air leak is a minor defect. The air-loss rate is a major defect when pressure drops in one minute more than 28 kPa (4 psi) for Class A or 21 kPa (3 psi) for Class D — test with wheels chocked, spring brakes released, pressure between cut-in and cut-out, brake pedal fully applied for one minute.

Key Rules
  • Build-up over two minutes from 85 to 100 psi is a minor defect
  • Air loss over 4 psi/min (Class A) or 3 psi/min (Class D) is a major defect
  • Any audible air leak is a minor defect requiring an air-loss rate test
🛑

Pushrod stroke measurement

airbrakes

A major defect exists when any brake's applied pushrod stroke exceeds its adjustment limit. Secure with chocks, ensure air above 621 kPa (90 psi), release spring brakes, mark or measure the released pushrod, build pressure to 90-100 psi, shut off engine, hold brakes applied, then measure the applied stroke. Determine the chamber number/type, its adjustment limit, and identify any brake exceeding it as defective. Some vehicles (buses, air disk brakes) are examined verbally.

Key Rules
  • A pushrod stroke exceeding the adjustment limit is a major defect
  • Measure applied stroke with air at 90-100 psi, engine off, brakes held fully applied
  • Determine chamber size and type to identify the correct adjustment limit
🛑

Tractor protection and low-air warning tests

airbrakes

An inoperative tractor protection valve is a major defect: with trailer supply valve closed and service brakes applied, no air should escape from the service-line coupler (glad-hand). The low-air warning system is a major defect if it fails to activate or activates before pressure drops below 55 psi — pump the brake pedal down and note when the warning (light or light and audible) activates.

Key Rules
  • Air escaping from the service line with supply valve closed indicates a defective tractor protection valve (major)
  • A low-air warning is a major defect if it fails or activates before 55 psi
  • Test the tractor protection valve with the trailer supply valve closed
🚛

Door, coupler and safety chain inspection

combination

A door meant for entry/exit failing to open is a minor defect; failing to close securely is a major defect. A coupler/mount with a loose or missing fastener is a minor defect. Fifth-wheel movement over 1/2 in. (13 mm) or pintle hook movement over 3/8 in. (10 mm) fore/aft is a major defect, as is a damaged coupler that fails to lock. A missing, wrong-type, or worn safety chain/cable is a major defect; chains must be hooked and crossed with a secondary hook.

Key Rules
  • Fifth-wheel play over 13 mm or pintle play over 10 mm is a major defect
  • A coupler that fails to lock properly is a major defect
  • Safety chains must be hooked and crossed; missing/wrong/worn chains are a major defect
  • A cab door failing to close securely is a major defect
📋

Exhaust, frame and fuel system defects

general

A noticeable exhaust leak is a minor defect; an exhaust leak letting gases into the cab is a major defect (inspect running with hood open). Frame/cargo body damage such as cracked/bent parts is a minor defect, but shifted, cracked, collapsing or sagging frame members are a major defect. A missing fuel cap is a minor defect; an insecure fuel tank or dripping fuel leak is a major defect.

Key Rules
  • Exhaust gases entering the cab are a major defect; a general exhaust leak is minor
  • Shifted, cracked, collapsing or sagging frame members are a major defect
  • An insecure fuel tank or dripping fuel leak is a major defect; a missing fuel cap is minor
📋

Glass, mirror and hydraulic brake inspection

general

Required mirrors or glass with broken or damaged attachments to the vehicle body are a minor defect — ensure all external mirrors and attachments are secure. For hydraulic brake systems, a minor defect exists when the brake fluid level is below the indicated minimum and the reservoir is less than one-quarter full; know the master-cylinder reservoir location and how to check fluid.

Key Rules
  • Broken or damaged required mirror/glass attachments are a minor defect
  • Brake fluid below minimum with reservoir under one-quarter full is a minor defect
🛑

Exterior inspection procedure

airbrakes

Exterior inspection is done with the parking brake engaged (for Class A and air-brake vehicles unless it must be released) and wheels chocked. You inspect four random items and must demonstrate/describe how to inspect, explain the possible defect(s), and describe what action to take for a minor or major defect.

Key Rules
  • Perform exterior inspection with parking brake engaged and wheels chocked
  • You must inspect four randomly generated items
  • For each item, describe the inspection, the defects, and the action to take

68.Intersections

📋

Stop Intersections

general

Approach monitoring traffic, watching for signage and traffic-control devices. Slow gradually, select appropriate gear, and stay in the same lane. Make a smooth full stop without rolling, stop in the proper legal position, and monitor traffic while waiting.

Key Rules
  • Stay in the same lane approaching the intersection
  • Make a full stop without rolling backward or forward
  • Stop in the proper legal position; do not stop in the intersection
  • Start movement within a reasonable time when permitted
📋

Starting from a Stop Intersection

general

Before entering, monitor traffic ahead. Start within a reasonable time when permitted by the light or vehicle ahead and travel through in reasonable time. Maintain a two-handed grip and follow the correct pathway without changing lanes in the intersection.

Key Rules
  • Start movement within a reasonable time when permitted
  • Maintain a two-handed grip except when operating controls or shifting
  • Do not change lanes or position within the intersection
📋

Through Intersections

general

Maintain speed to avoid disrupting traffic flow, but slow or cover the brake if cross traffic may enter. Keep a safe following distance and stay in the same lane. Make necessary shifts before entering and check mirrors after clearing.

Key Rules
  • Maintain speed approaching, but slow or cover the brake for potential cross traffic
  • Stay in the same lane/position through the intersection
  • Make any transmission shifts before entering; downshift if needed to avoid lugging
  • Check mirrors after clearing the intersection

69.Emergency vehicles

📋

Reacting to an approaching emergency vehicle

general

When you see red or red and blue flashing lights or hear sirens from either direction, immediately slow down, move as far right as possible and stop. React calmly using signals, check mirrors, pull right and stop gradually, wait for the vehicle to pass and watch for others. Do not block freeway shoulders. Never follow within 150 metres of a fire vehicle or ambulance responding to a call. Yield to volunteer responders showing a flashing green light.

Key Rules
  • Immediately slow down, move to the right and stop for an approaching emergency vehicle
  • It is illegal to follow within 150 metres of a responding fire vehicle or ambulance
  • Yield the right-of-way to a firefighter or volunteer responder displaying a flashing green light
📋

Reacting to a stopped emergency vehicle or tow truck

general

When you see a stopped emergency vehicle with red/blue lights or a tow truck with amber lights flashing in your direction of travel, slow down and pass with caution. On a road with two or more lanes, move over to leave one lane clearance if it can be done safely. Failing to comply can bring a conviction, demerit points, up to two years licence suspension, fines of $400-$2,000 first offence ($1,000-$4,000 subsequent within 5 years) and up to six months in jail.

Key Rules
  • Slow down and pass a stopped emergency vehicle or tow truck with caution
  • On roads with two or more lanes, move over to leave one lane clearance when safe
  • Violations carry fines, demerit points, licence suspension and possible jail time

70.Uncoupling and Coupling of Combinations (Class A only)

🚛

Pre-Coupling/Uncoupling Precautions

combination

Before any uncoupling/coupling procedure, roll down windows and turn off audio systems, sound your horn before backing (electric horn only during the road test), and confirm the location is suitable and safe. Knowing correct coupling and uncoupling is basic to safe combination vehicle operation.

Key Rules
  • Roll down windows and turn off audio systems before coupling/uncoupling
  • Sound your horn before backing (electric horn only during the road test)
  • Confirm the location is suitable and safe for coupling/uncoupling
🚛

Uncoupling Procedure

combination

To uncouple: secure both truck/tractor and trailer (apply both parking brakes, transmission in park/neutral, chock trailer wheels), lower the landing gear until just above/contacting ground without raising the trailer, disconnect and stow air/electrical lines and safety chains, unlock the fifth wheel/coupling device, disengage the fifth wheel by pulling the tractor forward, confirm the trailer is stable, then pull the tractor clear.

Key Rules
  • Apply both truck/tractor and trailer parking brakes and chock trailer wheels
  • Lower landing gear until just above or contacting ground without raising trailer off fifth wheel
  • Disconnect and stow air/electrical lines and safety chains before pulling clear
🚛

Coupling Procedure and Alignment

combination

To couple: inspect fifth wheel, coupling device, lines and chain points; position units and check alignment/height; reverse slowly until the fifth wheel is just ahead of the trailer touching or slightly under but not against the kingpin. The trailer should be low enough to be raised slightly by the tractor. If too low the tractor may damage the trailer nose; if too high it may not couple correctly.

Key Rules
  • Reverse until the fifth wheel is just ahead of the trailer, not against the kingpin
  • The trailer should be low enough to be raised slightly by the tractor when backed under
  • If the trailer is too high it may not couple correctly; if too low it may damage the trailer nose
🚛

Engaging and Confirming the Coupling

combination

After reversing to engage the fifth wheel, perform a tug test by stretching tractor and trailer to confirm the trailer is locked. Then exit and visually confirm there is no space above the fifth wheel, the release lever is locked, and the jaws/latch have closed around the kingpin (must get under trailer). For non-fifth wheel, connect safety chains crossed.

Key Rules
  • Perform a tug test to confirm the trailer is locked onto the tractor
  • Any space between the trailer upper plate and fifth wheel indicates the coupling is not secure
  • Visually confirm the release lever is locked and jaws closed around the kingpin from under the trailer
🛑

Air Line Colours and Final Coupling Steps

airbrakes

Industry standard air line colours: BLUE for service, RED for supply/emergency. After connecting lines, raise landing gear fully and stow the handle, supply air to the trailer to establish normal pressure, shut off the engine and listen for leakage at supply and service connections, then test brake operation by driving forward slowly.

Key Rules
  • Industry standard: BLUE = service, RED = supply or emergency
  • Raise the trailer landing gear fully and stow the handle before moving
  • Supply air and listen for leakage, then test brake operation by driving forward slowly
🚛

Testing the Hook-up

combination

To test the hook-up, place transmission in reverse and partially release the clutch to move the power unit backward in a short sharp motion ('hitting the pin'). Then set trailer brakes (hand control or parking brake) and try to pull forward against the pin. Then perform a visual coupling inspection under the trailer.

Key Rules
  • 'Hitting the pin' tests the hook-up by moving the power unit backward sharply
  • Set the trailer brakes then try to pull forward against the pin to confirm locking
  • Leave the cab and visually inspect that the upper plate rests firmly on the fifth wheel

71.Dealing with Emergencies

📋

Emergency Warning Devices and Procedures

general

Every commercial motor vehicle on a provincial highway during limited-visibility hours must carry sufficient emergency warning devices. When disabled, take actions to safeguard the vehicle and other motorists.

Key Rules
  • Must carry flares/lamps/lanterns producing two warning lights each visible from at least 150 metres (500 ft.) for at least eight hours, or portable reflectors
  • Turn on emergency flashers; use low-beam headlights when visibility is limited
  • In a speed zone greater than 60 km/h, if you cannot move the vehicle off the roadway, set out warning devices approximately 30 metres (100 ft.) to both front and rear during limited visibility
  • Times of limited visibility are one-half hour before sunset to one-half hour after sunrise and other poor light conditions preventing clear visibility beyond 150 metres
📋

Collision with Injuries or Fuel Leak

general

Every driver involved in a collision must stay at or return to the scene and give all possible assistance. Take steps to protect people and property when there are injuries or a fuel leak.

Key Rules
  • Do not move vehicles, turn off all engines and warn approaching drivers
  • By law, report any collision to police when there are injuries or damage exceeding $5,000
  • Do not allow smoking or flares near vehicles in case of fuel leak; leave injured people where they are unless there is danger of fire
  • Cover injured people to reduce shock and stay with them until help arrives
📋

Fire Precautions and Fire Classes

general

Commercial drivers should know how to prevent fires and use the correct extinguisher for each fire class. Common causes include soft tires, overheated brakes and fuel leaks.

Key Rules
  • Class A: wood, paper, textiles, tires; Class B: grease, oil, gasoline, solvents, paints; Class C: live electrical equipment; Class D: burning metals
  • When a fire occurs, stop in a safe position away from buildings/vehicles and uncouple a combination unit if possible
  • Contact the fire department and tell them what type of material is burning
  • If the fire is due to a short-circuit, remove battery cables; if cargo is explosive, stop traffic and warn spectators
📋

Collision with No Injuries

general

In a collision with no injuries, follow specific steps including exchanging information and reporting when required.

Key Rules
  • Give police your name and address, the registered owner's name and address, the vehicle plate and permit number, and the liability insurance card
  • If damage is less than $5,000, you must still exchange information but the collision does not have to be reported to police
  • Get names, addresses and phone numbers of all witnesses and contact your insurance company if making a claim

72.Lane Changes

📋

Performing a Lane Change

general

Observe traffic to identify where and when to change lanes, signal, maintain safe spacing, check mirrors and blind spots, and make a deliberate but smooth change. Avoid sudden or hesitant movements. Do not change lanes at intersections, crossings or over solid lines.

Key Rules
  • Signal before the change and cancel it once complete
  • Check mirrors and blind spots for vehicles alongside, passing or approaching from the rear
  • Ensure the target-lane gap is adequate for the vehicle's length
  • Do not change lanes at intersections, pedestrian/railway crossings or over solid pavement markings
  • Operate within 10 km/h of the posted limit without exceeding it

73.Dealing with emergencies

📋

Emergency warning devices

general

Every commercial motor vehicle on a provincial highway from a half-hour before sunset to a half-hour after sunrise must carry either flares/lamps/lanterns producing two warning lights visible at least 150 metres (500 ft.) for at least eight hours, or portable reflectors. In a zone over 60 km/h, if you cannot move the vehicle off the road, set out warning devices about 30 metres (100 ft.) to front and rear during limited visibility. Recommended for all emergencies.

Key Rules
  • Carry flares/lamps/lanterns (two lights visible 150 m for 8 hours) or portable reflectors
  • In zones over 60 km/h place warning devices about 30 metres (100 ft.) to the front and rear
  • Warning devices are required during times of limited visibility (half hour before sunset to after sunrise)
📋

Collision with injuries or fuel leak

general

Carry a well-stocked first-aid kit. Every driver in a collision must stay or return and give all possible assistance. With injuries or fuel leaks: set out warning devices with caution near leaks, do not move vehicles, turn off engines, warn approaching drivers, call for help. Report collisions with injuries or damage over $5,000 to police. Prevent smoking/matches near fuel leaks. Leave injured people in place unless there is fire danger. Treat within your first-aid training or cover for shock. Stay with injured until help arrives.

Key Rules
  • Report any collision with injuries or property damage exceeding $5,000 to police
  • Do not move vehicles, turn off engines and warn approaching drivers
  • Do not let anyone smoke or light matches near a possible fuel leak
  • Leave injured people in place until medical help arrives unless there is fire danger
📋

Parking and disabled vehicle rules

general

Move a disabled vehicle as far off the roadway as safely possible. Turn on emergency flashers and, in limited visibility, low-beam headlights. Do not park or leave a vehicle on a roadway unless it cannot be moved off, or unless there is a clear view of at least 125 metres (400 ft.) in both directions. If the vehicle's view is blocked by a hill or curve within 150 metres (500 ft.), place an additional warning signal.

Key Rules
  • Move a disabled vehicle as far off the roadway as safely possible and turn on flashers
  • Do not park on a roadway unless there is a clear view of at least 125 metres (400 ft.) both directions
  • Place an additional warning signal if the vehicle's view is blocked within 150 metres by a hill or curve
📋

Fire precautions and classes

general

Know fire classes: A (wood, paper, textiles, tires), B (grease, oil, gasoline, solvents, paints), C (live electrical equipment), D (burning metals like magnesium, sodium, potassium requiring special compounds). Common truck fire causes include soft tires, overheated brakes, leaking fuel systems, unequal load, careless smoking, misplaced flares and short circuits. Check hub temperatures when checking tires. Never smoke while loading/unloading.

Key Rules
  • Class A: ordinary combustibles; Class B: flammable liquids; Class C: electrical; Class D: metals
  • Class D metal fires require special compounds suitable to the combustible metal
  • Check hub temperatures every time tires are checked to detect overheated brakes
  • Never smoke while loading or unloading
🚛

Actions when a fire occurs

combination

When a fire occurs: stop the vehicle in a safe position away from buildings and other vehicles; if a combination unit, uncouple it if possible; contact the fire department and tell them what material is burning; take steps to extinguish based on the fire type; if a short-circuit is suspected, remove battery cables; if the cargo is explosive, stop traffic and warn spectators to stay back.

Key Rules
  • Stop the vehicle away from buildings and vehicles and uncouple a combination unit if possible
  • Tell the fire department what type of material is burning
  • If a short-circuit is suspected, remove the battery cables
  • For explosive cargo, stop traffic and warn spectators to stay back
📋

Collision with no injuries

general

When no one is injured: set out warning devices with caution, call police if damage exceeds $5,000, give all possible help and provide your name, address, owner's info, plate/permit number and insurance card. Get witness names and contacts. If damage is under $5,000 you must still exchange information but need not report to police. Contact your insurance company if making a claim.

Key Rules
  • Report to police if damage exceeds $5,000
  • Exchange information (name, address, owner, plate/permit, insurance) even for damage under $5,000
  • Get names, addresses and phone numbers of all witnesses

74.Air brake inspection items

🛑

Slow air pressure build-up rate

airbrakes

A vehicle has this minor defect when it takes longer than two minutes for air pressure to build from 85 to 100 psi. Procedure: close trailer supply valve, pump brakes to 80 psi or less, maintain 600–900 RPM, and time the rise from 85 to 100 psi (587 to 690 kPa), then report the time.

Key Rules
  • Slow build-up is a minor defect when 85-100 psi takes longer than two minutes
  • Maintain engine speed of 600-900 RPM while timing the build-up
  • Report the build-up time to the examiner
🛑

Audible air leaks

airbrakes

A vehicle has this minor defect when any air leak can be heard. Leaks must be checked for regularly.

Key Rules
  • An audible air leak is a minor defect
  • Check for air leaks regularly
🛑

Air loss rate exceeds prescribed limit

airbrakes

This major defect occurs when air pressure drops in one minute by more than 28 kPa (4 psi) for Class A or 21 kPa (3 psi) for Class D. Procedure: secure with chocks, release spring brakes, ensure pressure is between cut-in/cut-out (80–145 psi), shut off engine, hold brake pedal fully applied, and observe gauges for one minute (disregard the initial drop).

Key Rules
  • Air loss over 4 psi/min (Class A) or 3 psi/min (Class D) is a major defect
  • Release spring brakes and hold the brake pedal fully applied to test
  • Observe gauges for one minute after pressure stabilizes
🛑

Pushrod stroke exceeds adjustment limit

airbrakes

This major defect exists when any brake's pushrod stroke is longer than the prescribed limit. Secure vehicle, ensure air above 90 psi, release spring brakes, mark or measure released pushrod position, build pressure to 90–100 psi, shut off engine, hold brakes fully applied, then measure applied stroke. Determine chamber size (16/20/24/30) and type (standard/long-stroke) and compare to the adjustment limit. Some vehicles are examined verbally.

Key Rules
  • Excessive pushrod stroke on any brake is a major defect
  • Ensure air above 90 psi and build to 90-100 psi before measuring applied stroke
  • Determine chamber size and type and compare stroke to the adjustment limit
🛑

Low-air warning system failure

airbrakes

This major defect occurs when the low-air warning fails to activate or activates before pressure drops below 55 psi. Procedure: ensure air above 90 psi, ignition on, pump the brake pedal to lower pressure until the warning activates, and note the pressure at activation.

Key Rules
  • Warning failing to activate or activating below 55 psi is a major defect
  • Ignition must be on for the low-air warning to activate
  • Pump the brake pedal to lower pressure and note the activation pressure
🛑

Tractor protection valve inoperative

airbrakes

This major defect occurs when air escapes from the service line during a service-brake application while the trailer supply valve is closed. Procedure: keep pressure in normal range (80–135 psi), close the trailer supply valve, remove the trailer service-line glad-hand and place it observable, apply service brakes, and check for escaping air.

Key Rules
  • Air escaping from the service line with the supply valve closed is a major defect
  • Close the trailer supply valve and remove the service-line glad-hand to test
  • Release spring brakes first if there is no anti-compounding valve

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← Back to the Ontario study guide 1. Turning (Right and Left Turns) +72. Temporary condition signs +93. A and D Licence Classes and Requirements +94. In-cab Check +75. Commercial Vehicle Operator Registration (CVOR) +136. Driving in roundabouts +118. Lane changes +179. Stopping at School Crossings and for School Buses +5

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