Braking systems
63 questions
What this topic tests
Air brakes, endurance brakes and what happens when they get hot. The topic rewards knowing which brake is for which job, because most of the wrong answers are the right action applied to the wrong system.
- The service brake is the principal system. The endurance brake, or retarder, is what holds your speed on a long descent.
- Brake fade comes from continuous use; a lower gear and the retarder are the answer.
- An air-pressure warning light means stop and get help, not press on.
- Do not pump anti-lock brakes — it reduces their effectiveness.
- On a three-line system the additional line is the auxiliary.
The mark people lose: Using the service brake to hold your speed downhill. That is what makes brakes fade, and avoiding it is the whole purpose of the retarder.
- A lorry is overtaking you on a two-lane motorway. What should you do if it does not have the speed to get past?
- Air-brake systems usually have 2 lines. Which additional line is fitted on a three-line system?
- 'Brake fade' is a loss of effectiveness of the brakes when they overheat. When would 'brake fade' be most likely to happen?
- How can a lorry driver avoid brake fade?
- How can you help to prevent 'brake fade'?
- How will anti-lock brakes improve your vehicle's safety?
- In frosty weather, what precaution could a lorry driver take to prevent moisture from freezing in the air-brake system?
- The emergency line is common to both two-line and three-line brake systems. What colour is it?
- What can coasting downhill seriously affect?
- What causes 'brake fade'?
- What colour is the auxiliary line on a three-line braking system?
- What could prevent air pressure from building up in an air-brake system in frosty weather?
- What does changing to a lower gear on a long downhill gradient help to avoid?
- What should anti-lock brakes let you do when you have to stop in an emergency?
- What should you avoid when using an independent endurance brake (retarder) on slippery roads?
- What should you do after driving through a flood?
- What should you do if the brake air-pressure warning light comes on while you're driving?
- What should you do when an air-pressure warning device activates?
- What should you do when driving a large vehicle down a steep hill?
- What should you do when making a short stop, facing uphill?
- What system is used to control a vehicle's speed without using the footbrake?
- What will 'pumping' the brake pedal in a vehicle fitted with anti-lock brakes cause?
- What's an advantage of progressive braking?
- What's 'brake fade'?
- What's the most powerful brake on a bus?
- What's the principal braking system on a lorry called?
- When are exhaust brakes most efficient?
- When can an endurance brake (retarder) be especially useful?
- When does 'brake fade' occur?
- When is an articulated vehicle most at risk of jack-knifing?
- When is trailer swing most likely to occur on a lorry and drawbar combination?
- When should an anti-lock braking system (ABS) warning light turn off?
- When should an endurance brake (retarder) be used?
- Where must extra care be taken when using an endurance brake (retarder)?
- Which coloured band on the rev counter makes the best use of engine braking?
- Which component will last longer when you use a retarder?
- You have to drive onto a muddy building site. Why should you switch on your diff-lock?
- Your lorry is equipped with anti-lock brakes. What's the correct procedure for stopping in an emergency?
- Your lorry is stuck in snow. You use the diff-lock to move off. When should you switch the diff-lock off?
- Your tractor unit has 3 air lines. You're connecting to a trailer that has 2 air-line couplings. What colour is the line you should not connect to the trailer?
- Your vehicle has anti-lock brakes. How does this affect you when you're braking normally?
- Your vehicle is fitted with a 'diff-lock'. When would you normally use it?
- Your vehicle is fitted with air-assisted hydraulic brakes. What fault would you suspect if the brake pedal becomes hard to press?
- Your vehicle is fitted with air-assisted hydraulic brakes. What would warn you that there’s not enough air in the system?
- Your vehicle is fitted with air brakes. What does it mean if a brake warning light shows when you've just started the engine?
- Your vehicle is fitted with an air-assisted hydraulic braking system. What would warn you that the air compressor is not working?
- Your vehicle is fitted with an anti-lock braking system. What's it designed to allow you to do?
- Your vehicle is fitted with an anti-lock braking system. When should you check that it's working properly?
- Your vehicle is fitted with hydraulic brakes. Why might the brake pedal go down too far when it's pressed?
- Your vehicle is fully loaded. Where should you be braking when dealing with bends?
- You're about to drive a vehicle fitted with air-assisted hydraulic brakes. Why might the brake pedal feel hard when you press it?
- You're about to drive a vehicle fitted with hydraulic brakes. What should you check before driving the vehicle?
- You're about to drive an unfamiliar vehicle. What should you do if you think there may be moisture in the air-brake reservoir?
- You're about to move off in a vehicle that has automatic transmission. What must you do before you select 'D' (drive)?
- You're about to start a journey in very frosty weather. What's the likely cause of low air-brake pressure?
- You're driving a tractor unit fitted with 2 air lines. You want to couple to a trailer that has 3 air-line couplings. How should the air lines be connected?
- You're driving a vehicle fitted with anti-lock brakes. What should you do when braking in an emergency?
- You're driving an articulated lorry that has 3 air lines connected to the trailer. What's the purpose of the red line?
- You're driving an articulated lorry. What could happen if you change to a lower gear while you're going too fast?
- You're driving down a long hill. What should you use to prevent the brakes from overheating?
- You're driving down a snow-covered hill. Why should you take care when using an independent endurance brake (retarder)?
- You're stationary. The brake air-pressure warning light comes on. Why should you keep the parking brake on?
- You've just started the engine. What must you do if the brake air-pressure warning light is showing?