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218Driving and operating
Natural gas
The fuel consumption information
was obtained using reference fuel
G20 (methane proportion
99 - 100 mol%) under prescribed
driving conditions. When using
natural gas with a lower proportion of
methane, the fuel consumption can
differ from the specified values.Trailer hitch
General information
Only use towing equipment that has
been approved for your vehicle.
Vehicles with natural gas engines
require special towing equipment.
Entrust retrofitting of towing
equipment to a workshop. It may be
necessary to make changes that
affect the cooling system, heat
shields or other equipment.
The bulb outage detection function for
trailer brake light cannot detect a
partial bulb outage. E.g. in case of
4x 5 Watt bulbs, the function only
detects lamp outage when only a
single 5 Watt lamp remains or none
remain.
Fitting of towing equipment could
cover the opening of the towing eye.
If this is the case use the coupling ball bar for towing. Always keep the
coupling ball bar in the vehicle.Driving characteristics and
towing tips Before attaching a trailer, lubricatethe coupling ball. However, do not do
so if a stabiliser, which acts on the coupling ball, is being used to reduce snaking movements.
For trailers with low driving stability
and caravan trailers with a permitted
gross vehicle weight of more than
1300 kg the use of a stabiliser is
strongly recommended when driving
above 80 km/h.
If the trailer starts snaking, drive more slowly, do not attempt to correct the
steering and brake sharply if
necessary.
When driving downhill, drive in the
same gear as if driving uphill and
drive at a similar speed.
Adjust tyre pressure to the value
specified for full load 3 285.
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Driving and operating219Trailer towingTrailer loads
The permissible trailer loads are
vehicle and engine-dependent
maximum values which must not be
exceeded. The actual trailer load is
the difference between the actual
gross weight of the trailer and the
actual coupling socket load with the
trailer coupled.
The permissible trailer loads are
specified in the vehicle documents. In general, they are valid for gradients
up to max. 12 %.
The permitted trailer load applies up
to the specified incline and up to an
altitude of 1000 metres above sea
level. Since engine power decreases
as altitude increases due to the air
becoming thinner, therefore reducing
climbing ability, the permissible gross
train weight also decreases by 10 %
for every 1000 metres of additional
altitude. The gross train weight does
not have to be reduced when driving
on roads with slight inclines (less than
8 %, e.g. motorways).The permissible gross train weight
must not be exceeded. This weight is specified on the identification plate3 271.
Vertical coupling load
The vertical coupling load is the load
exerted by the trailer on the coupling
ball. It can be varied by changing the
weight distribution when loading the
trailer.
The maximum permissible vertical
coupling load (75 kg) is specified on
the towing equipment identification
plate and in the vehicle documents.
Always aim for the maximum load,
especially in the case of heavy
trailers. The vertical coupling load
should never fall below 25 kg.Rear axle load
When the trailer is coupled and the
towing vehicle fully loaded, the
permissible rear axle load (see
identification plate or vehicle
documents) may be exceeded by
60 kg , the gross vehicle weight rating
may be exceeded by 60 kg. If the
permissible rear axle load is
exceeded, a maximum speed of
100 km/h applies.
Towing equipmentCaution
When operating without a trailer,
remove the coupling ball bar.
Page 224 of 299
222Driving and operating
■The coupling ball bar must be firmly
engaged in the opening.
■ The coupling ball bar must be locked and the key removed.9 Warning
Towing a trailer is permitted only
when a coupling ball bar is fitted correctly. If the coupling ball bardoes not engage correctly, seekthe assistance of a workshop.
Dismounting the coupling ball
bar
Open the protective flap and turn the
key to position c to unlock the
coupling ball bar.
Pull out rotary handle and turn
clockwise as far as it will go. Pull out coupling ball bar downwards.
Insert sealing plug in opening. Fold away socket.
Trailer stability assist If the system detects snaking
movements, engine power is reduced
and the vehicle/trailer combination is
selectively braked until the snaking ceases. While system is working keep steering wheel as still as possible.
Trailer stability assist (TSA) is a
function of the Electronic Stability
Control 3 177.
Page 247 of 299
Vehicle care245
Remove the cover.
If equipped with tyre repair kit,
remove the complete box.
Fuse assignmentsNo.Circuit1–2Trailer outlet3Parking assist4Selective catalytic reduction
system5–6–7Power seat8–9Selective catalytic reduction
system10Nitrogen oxide sensor11Trailer module, trailer socket12Trailer module13Trailer outlet14–15–
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296
Tow bar....................................... 218
Towing ................................ 218, 262
Towing another vehicle .............263
Towing equipment .....................219
Towing the vehicle .....................262
Traction Control system ............. 176
Traction Control system off......... 114
Traffic sign assistant ...................204
Trailer coupling ........................... 218
Trailer stability assist .................222
Trailer towing ............................. 219
Transmission ............................... 18
Transmission display .................169
Tread depth ............................... 250
Trip computer ............................ 127
Trip odometer ............................ 104
Turn and lane-change signals ...145
Turn signal ................................. 110
Tyre chains ................................ 252
Tyre designations ......................247
Tyre pressure ............................ 247
Tyre pressure monitoring system ............................. 115, 248
Tyre pressures ........................... 285
Tyre repair kit ............................. 252
U Ultrasonic parking assist ...113, 194
Underseat storage .......................68
Upholstery .................................. 266Upshift........................................ 113
Using this manual ..........................3
V Vehicle battery ........................... 228
Vehicle checks............................ 224
Vehicle data ................................ 273
Vehicle data recording and privacy ..................................... 289
Vehicle detected ahead ..............116
Vehicle dimensions .................... 283
Vehicle Identification Number ....271
Vehicle jack ................................ 246
Vehicle messages .....................123
Vehicle personalisation .............130
Vehicle security ............................ 27
Vehicle specific data ......................3
Vehicle storage ........................... 223
Vehicle tools ............................... 246
Vehicle unlocking ........................... 6 Vehicle weight ........................... 281
Ventilation ................................... 150
W
Warning chimes .........................126
Warning lights ............................. 104
Warning triangle .......................... 92
Washer and wiper systems .........16
Washer fluid ............................... 227
Wheel changing .........................255Wheel covers ............................. 251
Wheels and tyres .......................247
Windows ....................................... 32
Windscreen................................... 32 Windscreen wiper/washer ...........98
Winter tyres ............................... 247
Wiper blade replacement ..........230