Vehicle knowledge, tyres and technical checks
Swiss exam items on vehicle knowledge are practical: tread depth, tyre pressure, warning lights, when winter tyres are needed and what the periodic inspection covers. You are expected to know the legal minimums and the reason behind them.
Tyres
- Legal minimum tread depth is 1.6 mm across the main grooves; 3–4 mm is the sensible minimum for wet grip, and winter tyres need about 4 mm to work.
- Check pressure when tyres are cold, using the figures in the manual or on the fuel flap. Under-inflation causes heat build-up, poor handling, higher fuel use and faster wear.
- Tyres age: check the DOT week/year code and replace at roughly 10 years regardless of tread.
- Winter tyres: since 2021 only tyres with the three-peak mountain snowflake (3PMSF) symbol count as genuine winter tyres in Switzerland; M+S alone no longer qualifies. They are not compulsory everywhere, but you must be able to control the vehicle in wintry conditions.
- Snow chains go on the driven wheels only; drive slowly, roughly 50 km/h maximum, and remove them on clear asphalt.
Regular checks and inspection
Weekly: lights and indicators, tyre condition and pressure, brake fluid level, oil and coolant, washer fluid and wipers. Warning lights in red mean stop as soon as it is safe. Periodic inspection (MFK) is cantonal, generally every two years, and the vehicle must be roadworthy at all times, not just on test day.
Worked example
A used car you are checking has 1.5 mm of tread on the front tyres and is fitted with M+S tyres without the snowflake symbol. Both points fail: 1.5 mm is below the legal 1.6 mm minimum, so the car is not roadworthy and would be refused at inspection; and the M+S tyres do not count as winter tyres for alpine conditions. The correct answer is new tyres, correct pressure, and a check of the rear pair and spare as well.
Traps that cost marks
- Measuring tread over the wear indicator and thinking it is fine.
- Setting pressure when the tyres are hot, so they end up under-inflated.
- Mixing radial and cross-ply tyres, or different sizes on one axle.
- Fitting chains to the front wheels of a rear-wheel-drive car.
- Assuming a service replaces the inspection obligation.