Motor vehicles (cars, vans, trucks and buses) and motorcycles must have their headlights on when being driven during daylight hours. Exempted from this requirement are mopeds, e-bikes and bicycles, and vehicles that were registered before 1970. Anyone who fails to comply with the requirement to drive with headlights on will be fined CHF 40.
In principle, you have to pay any fines you may get abroad. This will avoid any problems you may have when re-entering the country in question. This applies to Swiss drivers abroad and drivers from other countries in Switzerland. Please refer to the following FAQs: Traffic offences abroad