Date of printing:

05/16/2022

Online Owner's Manual [In depth | Driving and parking | Trailer towing]

Owner's Manual version: 06-13

Note: The online Owner's Manual is the latest version available. Deviations between this manual and items specific to your vehicle may occur since Mercedes-Benz constantly adapts its vehicles to the latest technology and modifies design and equipment. Please note that this online Owner's Manual does not under any circumstances replace the printed Owner's Manual which is supplied with the vehicle.

Trailer towing

Print page

Quick access

Contents

Notes on towing a trailer
Fitting the ball coupling
Removing the ball coupling
Coupling up a trailer
Decoupling a trailer
Trailer power supply
Bulb failure indicator for LED lamps
Trailers with a 7-pin connector

Notes on towing a trailer

Important safety notes

../../../../global/pictures_mb/symb_achtung.png

WARNING

If the ball coupling is not properly engaged, it could come loose and endanger other road users. There is a risk of an accident and injury.

Engage the ball coupling as described.

../../../../global/pictures_mb/symb_achtung.png

WARNING

If the maximum the permissible load for a carrier system is exceeded, the carrier could come loose from the vehicle and endanger other road users. There is a risk of an accident and injury.

Never exceed the permissible noseweight when using a carrier.

../../../../global/pictures_mb/symb_achtung.png

WARNING

You could lose control of the vehicle/trailer combination if it begins to swerve. The vehicle/trailer combination could even overturn. There is a risk of an accident.

On no account should you attempt to straighten out the vehicle/trailer combination by increasing speed. Decrease your speed and do not countersteer. Brake if necessary.

../../../../global/pictures_mb/symb_achtung.png

WARNING

The braking system can overheat if you leave your foot on the brake pedal while driving. This increases the braking distance and could even cause the braking system to fail. There is a risk of an accident.

Never use the brake pedal as a footrest. Do not simultaneously depress both the brake pedal and the accelerator pedal while driving.

../../../../global/pictures_mb/symb_ruf.png

Depressing the brake pedal constantly results in excessive and premature wear to the brake pads.

You can use carrier systems on the ball coupling, e.g. bicycle racks or load-bearing implements. The maximum noseweight of 75 kg applies when using carrier systems on the ball coupling.

Follow the manufacturer's operating instructions for the trailer tow hitch when using a detachable trailer tow hitch.

Couple and decouple the trailer carefully. When reversing the vehicle towards the trailer, make sure there is nobody between the trailer and the vehicle.

A trailer which is incorrectly coupled to the towing vehicle could break away. A correctly coupled trailer must be positioned horizontally behind the towing vehicle.

Ensure that the following weights are not exceeded:

  • the permissible noseweight

  • the permissible trailer load

  • the permissible rear axle load of the towing vehicle

  • the maximum permissible gross vehicle weight of both the towing vehicle and the trailer

  • the permissible gross combination weight

The applicable permissible values that may not be exceeded can be found:

  • in your vehicle documents

  • on the type plates for the trailer tow hitch

  • on the type plates for the trailer

  • on the vehicle identification plate more.

Where the values differ, the lowest is valid.

You will find the values approved by the manufacturer on the vehicle identification plates and those for the towing vehicle in the "Technical data" section more

When towing a trailer, your vehicle's handling characteristics will be different in comparison to when driving without a trailer.

The vehicle/trailer combination:

  • is heavier

  • is restricted in its acceleration and gradient-climbing capability

  • has an increased braking distance

  • is more susceptible to strong crosswinds

  • requires more sensitive steering

  • has a larger turning circle

This may impair the handling characteristics.

When towing a trailer, always adjust your speed to suit the road and weather conditions. Drive carefully. Maintain a safe distance.

General notes

../../../../global/pictures_mb/symb_ruf.png

Use a drawbar noseweight that is as close as possible to the maximum permissible noseweight. Do not fall below a noseweight of 50 kg, otherwise the trailer may come loose.

  • Do not exceed the legally prescribed maximum speed for vehicle/trailer combinations in the relevant country. Before beginning the journey, check the trailer's documents for the maximum permitted speed. In Germany, the maximum permissible speed is 80 km/h (100 km/h in exceptional cases).

  • The turn signals on the trailer are only guaranteed to work when incandescent bulbs are used. You can obtain more information on the installation of trailer electrics at any qualified specialist workshop.

  • When towing a trailer, set the tyre pressure for the rear axle of the towing vehicle to the setting for a fully laden vehicle more.

  • The trailer tow hitch is one of the most important components on the vehicle with regard to road safety. Observe the notes on operation, care and maintenance in the manufacturer's operating instructions.

  • Minimise the risk of damage to the ball coupling. If you do not require the ball coupling, remove it from the ball coupling recess.

../../../../global/pictures_mb/symb_info.png

For vehicles with passenger vehicle approval, the permissible gross vehicle weight is increased by 100 kg. The permissible gross vehicle weight must be observed.

You will find information about installation dimensions and loads in the "Technical data" section more.

../../../../global/pictures_mb/symb_info.png

The height of the ball coupling changes with the load of the vehicle. If this is case, use a trailer with a height-adjustable trailer drawbar.

Driving tips

When towing a trailer, your vehicle's handling characteristics will be different in comparison to when driving without a trailer and it will consume more fuel.

On long and steep downhill gradients, select a lower gear or shift range 3, 2 or 1.

../../../../global/pictures_mb/symb_info.png

This also applies if cruise control or SPEEDTRONIC is activated.

You thereby make use of the braking effect of the engine and do not have to brake as often to maintain the speed. This relieves the load on the brake system and prevents the brakes from overheating and wearing too quickly. If you need additional braking, depress the brake pedal repeatedly rather than continuously.

Observe the notes on ESP® trailer stabilisation more.

Driving tips

If the trailer begins to swing from side to side:

Do not accelerate.

Do not counter-steer.

Brake if necessary.

  • Maintain a greater distance than you would when driving without towing a trailer.

  • Avoid sudden braking. Apply the brakes gently at first to allow the trailer brake to overrun. Then, increase the brake force quickly.

  • The figures for the gradient climbing capabilities from a standstill refer to sea level. When driving in mountainous areas, note that the power output of the engine, and with it its gradient climbing capability, decrease with increasing altitude.

Nach oben

Fitting the ball coupling

../../../../global/pictures_mb/symb_achtung.png

WARNING

If the ball coupling is not properly engaged, it could come loose and endanger other road users. There is a risk of an accident and injury.

Engage the ball coupling as described.

../../../../global/pictures_mb/symb_achtung.png

WARNING

If the ball coupling is not correctly engaged, the trailer can detach. There is a risk of an accident.

Always engage the ball coupling as described.

Before you can tow a trailer with your vehicle, you must fit the ball coupling.

Make a note of the number on the key that comes with the ball coupling.

You can use this number to obtain a replacement key from a Mercedes-Benz Service Centre.

images/imgc0877eb3351f15145bbf482aae415af2_1_--_--_JPG72.jpg Example: cover beneath the bumper

Only vehicles with a narrow bumper are equipped with a cover for the ball coupling recess.

Push catches mbsymb6_inv_003a.png inwards in the direction of the arrow.

Pull cover mbsymb6_inv_003b.png down and out.

Take the ball coupling with its key out of the stowage space on the right-hand side of the rear compartment more and stow cover mbsymb6_inv_003b.png there.

images/img23dfd441fea20e4e35477e682ffa2ffa_1_--_--_JPG72.jpg

Pull protective cap mbsymb6_inv_003d.png off lock mbsymb6_inv_003f.png in handwheel mbsymb6_inv_0041.png.

Unlock lock mbsymb6_inv_003f.png in handwheel mbsymb6_inv_0041.png using the key. The red marking on ball coupling mbsymb6_inv_0042.png must be aligned with the green area on handwheel mbsymb6_inv_0041.png (fitting position).

images/imgf6f54d612565f5ed35477e684b944b94_1_--_--_JPG72.jpg

If red marking mbsymb6_inv_0044.png is not aligned with green area mbsymb6_inv_0043.png, unlock lock mbsymb6_inv_003f.png in handwheel mbsymb6_inv_0041.png using the key.

Pull handwheel mbsymb6_inv_0041.png outwards. Turn red marking mbsymb6_inv_0044.png to green area mbsymb6_inv_0043.png until handwheel mbsymb6_inv_0041.png engages.

images/img735be263ca13d800351f15147587c07a_1_--_--_JPG72.jpg

Push ball coupling mbsymb6_inv_0042.png vertically into the socket until you hear it engage.

The ball coupling locks into place automatically. The green marking on handwheel mbsymb6_inv_0041.png is aligned with green area mbsymb6_inv_0043.png on the ball coupling.

The ball coupling is only securely engaged when the green marking on the handwheel is aligned with the green area on the ball coupling.

images/img077a4046ca206a65351f15145346c098_1_--_--_JPG72.jpg

Lock lock mbsymb6_inv_003f.png in handwheel mbsymb6_inv_0041.png using the key.

Remove the key and replace cap mbsymb6_inv_003d.png.

Store the key in the stowage compartment on the right-hand side at the rear of the vehicle.

The ball coupling is only installed securely when the ball coupling can be locked and the key can be removed.

If you cannot remove the key, the ball coupling may be dirty.

Remove the ball coupling and clean it more.

If you cannot lock the ball coupling once you have cleaned it, the trailer tow hitch is damaged.

Remove the ball coupling.

Safe trailer-towing cannot be guaranteed. The ball coupling should no longer be used for trailer-towing.

Have the trailer coupling checked at a qualified specialist workshop.

Nach oben

Removing the ball coupling

../../../../global/pictures_mb/symb_achtung.png

WARNING

Never transport an unsecured ball coupling in the interior of the vehicle.

Otherwise, vehicle occupants could be injured by the ball coupling being thrown if you:

  • brake sharply

  • change direction suddenly

  • have an accident

images/img7f0ac599ca22e5ae351f151469d107bb_1_--_--_JPG72.jpg

Take the key for the ball coupling and the cover for the ball coupling recess on the vehicle out of the stowage space on the right-hand side of the rear compartment.

Pull protective cap mbsymb6_inv_003a.png off lock mbsymb6_inv_003b.png in handwheel mbsymb6_inv_003d.png.

Unlock lock mbsymb6_inv_003b.png in handwheel mbsymb6_inv_003d.png using the key.

images/img7684343efea8e1aa35477e6860b460b4_1_--_--_JPG72.jpg

Hold onto ball coupling mbsymb6_inv_003f.png.

Pull handwheel mbsymb6_inv_003d.png outwards. Turn red marking mbsymb6_inv_0042.png to green area mbsymb6_inv_0041.png until handwheel mbsymb6_inv_003d.png engages.

Pull out ball coupling mbsymb6_inv_003f.png downwards.

On vehicles with a narrow bumper, put the ball coupling recess cover back in place on the vehicle. Push the catches out to the sides and make sure that the cover is secure more.

Clean the ball coupling if it is dirty more.

Stow the ball coupling with key inserted in the stowage space on the right-hand side of the rear compartment.

Nach oben

Coupling up a trailer

images/imgd08139f1351f151411140431b22ee434_1_--_--_JPG72.jpg Trailer coupled ready for use

On vehicles with an automatic transmission, make sure that the selector lever is in position P.

Apply the parking brake.

Close all the doors.

Position the trailer horizontally behind your vehicle.

The height of the ball coupling changes with the load of the vehicle. If this is case, use a trailer with a height-adjustable trailer drawbar.

Couple the trailer.

Establish all electrical and other connections to the trailer.

Make sure that the trailer lights are functioning correctly.

Remove the objects that are preventing the trailer from rolling, e.g. wheel chocks.

Release the trailer parking brake.

Nach oben

Decoupling a trailer

../../../../global/pictures_mb/symb_achtung.png

WARNING

If you uncouple a trailer with an engaged overrun brake, you could trap your hand between the vehicle and the trailer drawbar. This poses a risk of injury.

Do not uncouple a trailer with an engaged overrun brake.

../../../../global/pictures_mb/symb_ruf.png

Do not disconnect a trailer with an engaged overrun brake. Otherwise, your vehicle could be damaged by the rebounding of the overrun brake.

On vehicles with an automatic transmission, make sure that the selector lever is in position P.

Apply the parking brake.

Close all the doors.

Apply the trailer parking brake.

In addition, secure the trailer against rolling away with a wheel chock or similar object.

Remove the trailer cable and decouple the trailer.

Nach oben

Trailer power supply

../../../../global/pictures_mb/symb_ruf.png

You can connect accessories with a power rating of up to 240 W to the permanent power supply and with a power rating of up to 180 W to the power supply that is switched on via the ignition lock.

The trailer battery may not be charged from the power supply.

When it leaves the factory, your vehicle's trailer socket is equipped with a permanent power supply and a power supply that is switched on via the ignition lock.

The permanent power supply is supplied via trailer socket pin 9.

The power supply which is activated when the key is in position 2 in the ignition is supplied via trailer socket pin 10.

The trailer's permanent power supply is switched off when the vehicle's on-board voltage is low.

The turn signals on the trailer are only guaranteed to work when incandescent bulbs are used.

You can find more information about installing the trailer electrics at a qualified specialist workshop.

Nach oben

Bulb failure indicator for LED lamps

If the trailer is equipped with LED lamps, mbsymb2_inv_0062.png indicator lamps in the instrument cluster may light up or the display may show a corresponding error message. The trailer lighting is identified as being faulty even though it is in working order. The reason for the error message may be that the current has fallen below the minimum of 50 mA.

To ensure reliable operation of the bulb failure indicator, each LED chain in the trailer lighting must be guaranteed a minimum current of 50 mA.

Nach oben

Trailers with a 7-pin connector

General notes

If your trailer is equipped with a 7-pin connector, you need to use an adapter plug or an adapter cable to make the connection. An adapter plug or adapter cable for the 13-pin vehicle socket can be obtained at a qualified specialist workshop.

Fitting the adapter

../../../../global/pictures_mb/symb_ruf.png

Make sure that there is sufficient cable play so that the cable cannot become detached when cornering.

images/imgfcd00fd9fea0317f35477e6827662766_1_--_--_JPG72.jpg

Open the vehicle socket cover.

Insert the adapter plug by lug mbsymb6_inv_003a.png into groove mbsymb6_inv_003b.png in the vehicle socket. Turn the adapter plug clockwise as far as it will go.

Close the cover so that it engages.

If you are using an adapter cable, use cable ties to secure the cable to the trailer.

Nach oben

Notes

Date of printing:

05/16/2022

Online Owner's Manual [In depth | Driving and parking | Trailer towing]

Owner's Manual version: 06-13

Note: The online Owner's Manual is the latest version available. Deviations between this manual and items specific to your vehicle may occur since Mercedes-Benz constantly adapts its vehicles to the latest technology and modifies design and equipment. Please note that this online Owner's Manual does not under any circumstances replace the printed Owner's Manual which is supplied with the vehicle.