Vehicle Knowledge
Vehicle knowledge questions check that you understand the main systems of a car or motorcycle well enough to spot trouble early, drive within the machine's limits, and explain why a warning light matters.
Systems you should be able to describe
- Brakes: hydraulic, with discs or drums, aided by ABS. ABS stops the wheels locking so you keep steering, but it does not shorten stopping distances on gravel or loose surfaces. Repeated heavy braking on a long descent overheats pads and fluid, causing brake fade - the pedal feels long and stopping power drops.
- Steering and suspension: power assistance, shock absorbers, springs. Worn dampers lengthen stopping distances and cause uneven tyre wear.
- Tyres: minimum tread 1.6 mm for cars across the central three-quarters of the tread, 1 mm for motorcycles. Check pressure when tyres are cold, and look for cuts, bulges and uneven wear that points to alignment or pressure faults. The sidewall date tells you the tyre's age.
- Lights: headlights, dipped beam, main beam, fog lamps, brake lights, indicators, hazard lights. A failed bulb is a defect, not a detail.
- Cooling and lubrication: check coolant only when the engine is cold; never open a hot radiator cap. Check oil on level ground. A red oil-pressure light means stop the engine.
- Emission control: catalytic converters and diesel particulate filters need occasional longer runs at speed to regenerate; short town trips clog them.
Dashboard warning lights
Red means stop safely and investigate. Amber means check soon. Green or blue simply shows a system is working.
Worked example
Descending from the Troodos with a fully loaded car, you smell hot brakes and the pedal travels further than usual. Riding the brakes has overheated them. Select a lower gear so engine braking holds the car back, use the brakes less and intermittently, and stop in a safe place to let them cool. Never pour cold water on hot discs - they can crack.
Load and towing
Roof loads raise the centre of gravity, so cornering and crosswind behaviour change. Stay within the manufacturer's roof and nose-weight limits and reduce speed when towing.
Traps that cost marks
- Driving on with a red oil-pressure or brake warning light.
- Checking tyre pressures after a long motorway run, when they read high.
- Believing ABS shortens every stopping distance.
- Topping up a hot cooling system.
- Ignoring a bulging sidewall because the tread still looks legal.