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161
Driving and operation
Check that the coupling ball bar is correctly installedzGreen marking on rotary knob must
point towards white ma rking on coupling
ball bar
z There must be no gap between the
rotary handle and the coupling ball bar
z The coupling ball bar must be firmly
engaged in the opening
z The coupling ball bar must be locked
and the key removed
Picture no: 12421t.tif
Eye for break-away stopping cable
In the case of trailers/caravans with brakes,
attach breakaway stopping cable to eye.
Picture no: 13670t.tif
Dismounting the coupling ball bar
Open the protective flap and turn the key
to position 1 to unlock the coupling ball bar
3 159, Fig. 12416 T.
Pull out rotary handle and turn clockwise
as far as it will go. Pull out coupling ball bar
downwards.
Insert the sealing plug in the opening for
the coupling ball bar. Close the socket
3 159, Fig. 15271 S.
9 Warning
Towing a caravan/trailer is only
permitted with a properly fitted coupling
ball bar. If the coupling ball bar cannot
be correctly fitted, please contact a
workshop for assistance.
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162 Driving and operation
Picture no: 17923s.tif
Stowage of coupling ball bar
Place coupling ball bar in bag and clip onto
the tool kit below the spare wheel 3159,
Fig. 14195 S.
On vehicles with tyre repair kit 3, the
coupling ball bar is stored in the left
stowage compartment beneath the floor
cover in the luggage compartment - see
Fig. above.
Caravan/trailer towingCaravan and trailer loads
1)
The permissible caravan/trailer loads are
vehicle and engine-dependent maximum
values which must not be exceeded. The
actual caravan/trailer load is the difference
between the actual gross weight of the
caravan/trailer and the actual coupling
socket load with the caravan/trailer
coupled.
The permissible caravan/trailer loads are
specified in the vehi cle documents. In
general, they are valid for gradients up to
maximum 12% The permitted caravan/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 because of the air becoming
thinner, therefore reducing climbing ability,
the permitted towing weight also
decreases by 10 % for
every 1000 metres of
additional altitude. The towing 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 weig ht is specified on
the identification plate 3218. 1)Observe national regulations.
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163
Driving and operation
Coupling socket load
The coupling socket load is the load
exerted by the trailer/caravan on the
coupling ball. It can be varied by changing
the weight distribution when loading the
trailer/caravan.
The maximum permissible coupling socket
load (55 kg) of the towing vehicle is
specified on the towing equipment
identification plate and in the vehicle
documents. This must always be complied
with, particularly in the case of heavy
caravans/trailers. The coupling socket load
should be no less than 25 kg.
When measuring the coupling socket load,
make sure that the drawbar of the loaded
trailer/caravan is at the same height as it
will be when the trailer/caravan is coupled
with the towing vehicle loaded. Particularly
important for trailers/caravans with
tandem axle. Rear axle load during towing
With the trailer connected and the towing
vehicle fully loaded including all
occupants, the permitted rear axle load
(specified on the identification plate and
vehicle documents) must be exceeded by
no more than 25 kg and the maximum
permitted gross vehicle weight by no more
than 30 kg. If the maximum permitted rear
axle load is exceeded, a maximum speed
of 100 km/h applies, and 80 km/h for
commercial vehicles.
Driving characteristics, towing tips
Before attaching th
e trailer/caravan,
lubricate the ball of the trailer/caravan
towing device. However, do not lubricate
the ball if a stabiliser, which acts on the
coupling ball, is being used to damp
hunting.
Check caravan/traile r lighting before
starting to drive. The fog tail lamps on the
vehicle are deactivated when towing a
caravan or trailer.
Trailers with LED turn signals must have a
provision enables lamp monitoring for
commercial bulbs.
Handling is greatly influenced by the
loading of the trailer/caravan. Loads
should therefore be secured so that they
cannot slip and be placed in the centre of
the trailer/caravan if possible, i.e. above
the axle.
In the case of trailers with low driving
stability, do not exceed a speed of 80 km/h;
the use of a friction-type stabiliser is
strongly recommended.
Page 170 of 248

164 Driving and operationIf the trailer/caravan starts to sway, drive
more slowly, do not attempt to correct the
steering and brake sharply if necessary.
If it is necessary to apply the brakes fully,
depress the brake pedal as hard as
possible.
Remember that the braking distance for
vehicles towing carava ns/trailers with and
without brake is always greater than that
for vehicles not towing a caravan/trailer.
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 3228. Starting on inclines
For vehicles with ma
nual transmission,
the most favourable engine speed
when starting off on an incline is
between 2500 and 3000 rpm for petrol
engines and between 2000 and 2500 rpm
for diesel engines. Hold engine speed
constant, engage clutch gradually (let slip)
– release hand brake – and open throttle. If
possible, the engine speed should not drop
during this procedure.
For vehicles with ma nual transmission
automated 3 in Automatic mode simply
apply full gas. Before starting off under extreme
operating conditions, switch off
unnecessary consumers.
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165
Self-help, vehicle care
Self-help, vehicle care
Diesel fuel system, bleeding If the tank is allowed to run dry, the diesel
fuel system must be bled. Turn over the
ignition three times for 15 seconds at a
time. Then start the engine for a maximum
of 40 seconds
1). Repeat this process after
no less than 5 seconds. If the engine fails to
start, seek the assistance of a workshop.
Picture no: 16109s.tif
Bonnet Pull the release lever lo cated on the driver’s
side below the instru ment panel and push
it back to its original position.
Diesel fuel system, bleeding ............... 165
Bonnet .................................................. 165
Starting the engine with jump
leads 3............................................. 166
Towing .................................................. 168
Warning triangle ¨ 3,
First-aid kit +3................................. 171
Jack £ 3 and vehicle tools 3............ 171
Spare wheel 3...................................... 172
Changing wheels ................................. 174
Tyre repair kit 3................................... 178
Electrical system .................................. 181
Fuses and the most important circuits they protect ....................................... 182
Bulb replacement ................................ 185
Vehicle care.......................................... 196
1)For technical reasons, only 30 seconds are
possible on engines Y 17 DT and Z 17 DTH
Page 174 of 248
168 Self-help, vehicle careRoute the leads so that they cannot catch
on rotating parts in the engine
compartment.
To start the engine:
1. Start the engine of the vehicle providing the jump start.
2. After 5 minutes, start the other engine. Start attempts shou ld be made at
intervals of 1 minute not last longer
than 15 seconds.
3. Allow both engines to idle for approx. 3 minutes with the leads connected.
4. Switch on electrical consumers (e.g. light, heated rear window) of the vehicle
receiving the jump start.
5. Reverse above sequence exactly when removing leads.
Picture no: 17896s.tif
Towing Towing your own vehicle
Disengage cap at bottom and remove
downwards.
Picture no: 14198s.tif
The towing eye is in the tool kit 3 in the
luggage compartment underneath the
spare wheel 3, see Fig. above, or for
versions with tyre repair kit 3, in the
storage compartment underneath the floor
cover, see Fig. 17918 S.
Page 175 of 248
169
Self-help, vehicle care
Picture no: 17918s.tif
Screw in the towing eye anticlockwise as far
as it will go until it stops in a horizontal
position.
Attach a tow rope 3 – or better still a tow
rod 3 – to the eye.
The towing eye may only be used for
towing and not for recovery of the vehicle. Switch on ignition to release steering
column lock and to permit operation of
brake lamps, horn an
d windscreen wipers.
Gear lever in neutral.
Picture no: 17897s.tif
When the engine is not running,
considerably more force is needed to brake
and steer.
To prevent the entry of exhaust fumes from
the towing vehicle, switch on the air
recirculation 3 and close the windows.
Contact a workshop for assistance.
Caution
Drive slowly. Do not drive jerkily.
Excessive tractive force can damage
the vehicle.
Page 176 of 248
170 Self-help, vehicle careIf the automatic clutch has been manually
disengaged in vehicles with manual
automated transmission 3 towing is not
permitted 3134. In this case, contact a
workshop for assistance immediately.
After towing, unscrew towing eye by
rotating clockwise and insert and close the
cap.
Picture no: 14199s.tif
Towing another vehicle
Attach a tow rope 3 – or better still a tow
rod 3 – to the rear towing eye on the right
side of the vehicle underbody, but never to
the rear axle.
Picture no: 17898s.tif
On some versions, the towing eye is located
behind a cover.
Slacken the screw a quarter turn with a
screwdriver (see Fig.) and remove the
cover.
The towing eye may only be used for
towing and not for recovery of the vehicle.
After towing, fit cover 3 and secure with
bolt.
Caution
Drive slowly. Do not drive jerkily.
Excessive tractive force can damage the
vehicle.