The **position lights** are essential for a vehicle to be **visible** to other road users. These lights indicate the **width** of the vehicle and are located at the front, rear, and sides. Their main function is to ensure that other drivers and pedestrians can see the vehicle, especially in low-light conditions.

- Position lights are used in situations such as night driving, passing through tunnels, or on dark days with little natural light. In these circumstances, they help make the vehicle visible to others.
- When the vehicle is in motion, the position lights turn on along with other lights. However, if the vehicle is stationary, such as in the case of a breakdown on a poorly lit road, the position lights can be turned on alone to ensure the vehicle is visible.

Therefore, the main function of the position lights is **to be seen by other road users**, ensuring the safety and visibility of the vehicle in various conditions.