To access the Trailers tab, the Trailers service should be enabled in the account properties. To work with trailers and their groups, the user should have the Create, edit, and delete trailers access right to the resource of the account.

In Wialon, trailers refer to additional equipment that is attached to the main vehicle and doesn't have its own tracker or controller. Monitoring trailers is similar to tracking drivers in many ways.

To work with trailers, click on the Trailers tab in the top panel or select a same-name item in the main menu customizer. You can work with trailers as well as their groups.

Video: Drivers, trailers, passengers | Basic

You can find information about the Trailers tab in the following video dated 02.06.2021: