Mercedes-Benz

Coupling up/uncoupling a trailer

WARNING Risk of injury from the vehicle level being changed

The vehicle level may be changed unintentionally, e.g. by other people. You may become trapped if you couple up or uncouple a trailer while this is happening. In addition, other people could become trapped if their limbs are between the vehicle body and the tyres or underneath the vehicle.

Observe the following when coupling up or uncoupling a trailer:

Do not open or close the doors or tailgate.

Do not lock or unlock the vehicle.

Requirements:

The ball neck is extended and engaged in a securely locked position.

Trailers with a 7-pin plug can be connected to the vehicle with the following adapters:

Adapter plug
Adapter cable

The trailer will be correctly detected by the vehicle only if the following conditions are met:

The trailer is connected correctly.
The trailer lighting system is in working order.

The functions of the following systems will be affected by a correctly connected trailer:

ESP® trailer stabilisation
Active Lane Keeping Assist
Parking Assist PARKTRONIC
Active Parking Assist
Blind Spot Assist or Active Blind Spot Assist
Drive Away Assist
Cross Traffic Alert
Reversing camera
360° camera

Coupling up a trailer

NOTE Damage to the starter battery due to full discharge

Charging the trailer battery using the power supply of the trailer can damage the starter battery.

Do not use the vehicle's power supply to charge the trailer battery.

Remove the cover cap from the ball head and store it in a safe place.

Position the trailer on a level surface behind the vehicle and couple it up to the vehicle.

Open the socket cap.

Insert the plug with lug

in groove

on the socket.

Turn bayonet coupling

to the right as far as it will go.

Let the cap engage.

Secure the cable to the trailer with cable ties (only if you are using an adapter cable).

Make sure that the cable is always slack for ease of movement during cornering.

Under the following conditions, a message may appear on the multifunction display even if the trailer has been connected correctly:

LEDs have been installed in the trailer lighting system.
The current has fallen below the trailer lighting system's minimum current (50 mA).

Accessories can be connected to the permanent power supply up to 180 W and to the power supply that is switched on via the ignition lock.

Uncoupling a trailer

WARNING Risk of being crushed and becoming trapped when uncoupling a trailer

When uncoupling a trailer with an engaged inertia-activated brake, your hand may become trapped between the vehicle and the trailer drawbar.

Do not uncouple trailers with an engaged overrun brake.

NOTE Damage when uncoupling in a state of overrun

Uncoupling in a state of overrun can damage the vehicle.

Do not uncouple trailers with an engaged overrun brake.

WARNING Risk of becoming trapped when disconnecting the trailer cable

Vehicles with level control system: The vehicle may lower when the trailer cable is disconnected.

This could result in you or other people becoming trapped if your or their limbs are between the vehicle body and the tyres or underneath the vehicle.

Make sure that nobody is underneath the vehicle or in the immediate vicinity of the wheel arches when you disconnect the trailer cable.

NOTE Damage to the rear bumper from installing adapter cables or adapter plugs

The following parts could be damaged when swiveling the ball neck fully electrically:

Bumper
Adapter cable
Adapter plug

Always remove the adapter cable or adapter plug before swiveling the ball neck fully electrically.

Secure the trailer against rolling away.

Disconnect the electrical connection between the vehicle and the trailer.

Uncouple the trailer.

Place the cover cap on the ball head.