If breakdown is due to mechanical malfunction, and there are no other people, vehicles or damage to property involved, follow these steps in order given:
The large, grey box in the trunk contains reflective vests (one per person) and a first aid kit. Details about where in the vehicle what has to be stowed varies from country to country. Avoid possible fines and troubles by reading about it before you set off.
If you had an accident where only your vehicle was damaged, follow these steps in order given:
If you had an accident where people (incl. yourself) got hurt, your vehicle or third party property was damaged, follow these steps in order given: