Vehicle knowledge, maintenance and environment
Domain 6 is the practical side of ownership: knowing when the car is unsafe, keeping it maintained, and driving in a way that limits fuel use and emissions.
Tyres and routine checks
Legal minimum tread is 1.6 mm across the central three quarters of the tyre. Check pressures monthly when the tyres are cold, against the manufacturer's figures, including the spare and the higher pressure used for a full load. Under-inflated tyres increase fuel consumption, wear the shoulders and lengthen braking distance.
Lights and fluids
Check bulbs regularly and keep the headlights clean, since grime scatters light and dazzles others. Engine oil is checked on level ground and must sit between the marks - overfilling damages seals. Never open the coolant reservoir while the engine is hot, and have brake fluid changed at the specified interval because it absorbs water over time.
Warning lights and inspection
A red warning light means stop safely and investigate: oil pressure, coolant temperature, brakes, battery or charging. An amber light allows a careful drive to a workshop. A new car receives its first periodic inspection (APK) at four years, after which the schedule continues; the test covers brakes, tyres, lights, suspension, steering and emissions.
Environment
Shift up early, hold a steady speed and anticipate so you can coast towards a red light instead of braking late. Correct tyre pressure, removing roof racks and clearing unnecessary weight all cut consumption. Short trips never warm the engine or catalytic converter, so they pollute proportionately more, and a diesel particulate filter needs regular longer runs to regenerate.
Worked example
A tyre reads 1.9 bar against a recommended 2.3 bar. Rolling resistance rises, so fuel use and shoulder wear increase, and the tyre heats up more at speed. Inflating to the correct cold pressure restores grip, braking and economy at no cost beyond a few minutes at a pump.
Traps that cost marks
- Checking tread only at the outer edge of the tyre.
- Opening the coolant cap while the engine is hot.
- Topping oil above the maximum mark.
- Ignoring an amber warning light for weeks.