138Driving and operatingTurn key briefly to position 3 and
release: an automatic procedure
operates the starter after a brief
delay, until the engine is running. See
'Automatic Starter Control'.
Before restarting or to switch off the
engine, turn the key back to position
0 .
During an Autostop, the engine can
be started by depressing the clutch
pedal.
Starting the vehicle at low
temperatures
Diesel engines
The start of the engine without
additional heaters is possible down to -25 °С.
Petrol engines
The start of the engine without
additional heaters is possible down to
-30 °C.
Required is an engine oil with the
correct viscosity, the correct fuel,
performed services and a sufficiently charged vehicle battery.With temperatures below -30 °C, the
automatic transmission requires a
warming phase of approx. five
minutes. The selector lever must be
in position P.
Automatic starter control This function controls the engine
starting procedure. The driver does
not need to hold the key in position 3.
Once applied, the system will go on
starting automatically until the engine
is running. Because of the checking
procedure, the engine starts running after a short delay.
Possible reasons for a non-starting engine:
● clutch pedal not operated (manual transmission)
● brake pedal not operated or selector lever not in P or N
(automatic transmission)
● timeout occurredTurbo engine warm-up
Upon start-up, engine available
torque may be limited for a short time, especially when the engine
temperature is cold. The limitation is
to allow the lubrication system to fully protect the engine.
Overrun cut-off The fuel supply is automatically cut-
off during overrun, i.e. when the
vehicle is driven with a gear engaged
but accelerator is released.
Stop-start system The stop-start system helps to save
fuel and to reduce the exhaust
emissions. When conditions allow, it
switches off the engine as soon as the
vehicle is at a low speed or at a
standstill, e.g. at a traffic light or in a
traffic jam.
On vehicles with manual
transmission, the engine is started
automatically as soon as the clutch is depressed.
Driving and operating179Fuel for liquid gas operation
Liquid gas is known as LPG
(Liquefied Petroleum Gas) or under
its French name GPL (Gaz de Pétrole Liquéfié). LPG is also known as
Autogas.
LPG consists mainly of propane and
butane. The octane rating is between 105 and 115, depending on the
butane proportion. LPG is stored
liquid at around five to ten bar
pressure.
The boiling point depends on the
pressure and mixing ratio. At ambient
pressure, it is between -42 °C (pure
propane) and -0.5 °C (pure butane).Caution
The system works at an ambient
temperature of approx. -8 °C to
100 °C.
Full function of the LPG system can
only be guaranteed with liquid gas
which complies with the minimum
requirements of DIN EN 589.
Fuel selector
Pressing LPG switches between
petrol and liquid gas operation as
soon as the required parameters (coolant temperature, gas
temperature and minimum engine
speed) have been reached. The
requirements are usually fulfilled after
approx. 60 seconds (depending on
exterior temperature) and the first firm press on the accelerator. The LED
status shows the current operating
mode.
LED off:petrol operationLED
flashes:checking conditions for
fuel transition to liquid
gas operation.
Illuminates if conditions
are fulfilled.LED illu‐
minates:liquid gas operationLED
flashes
five
times
and
extin‐
guishes:liquid gas tank is empty
or failure in liquid gas
system. A message is
displayed in the Driver
Information Centre.
If the fuel tank is empty, the engine
will not start.
The selected fuel mode is stored and reactivated at the next ignition cycle if
conditions allow.
As soon as the liquid gas tanks are
empty, petrol operation is
automatically engaged until the
ignition is switched off.
Every six months, run the petrol tank down until control indicator Y
illuminates, then refuel. This helps
maintain fuel quality and system
function for petrol operation.