The trailer socket of your vehicle is equipped at the factory with a permanent power supply.

The permanent power supply is supplied via trailer socket pin 4.

You can connect accessories with a maximum power consumption of 240 W to the permanent power supply.
You must not charge a trailer battery using the power supply.

The trailer's permanent power supply is switched off in the event of low vehicle supply voltage and after six hours at the latest.

You can obtain further information about installing the trailer electrics from a qualified specialist workshop, e.g. an authorized Mercedes-Benz Center.