Start and driving
Since the luggage rack increases the aero-
dynamic drag of the vehicle, you should re-
move it when not needed. At speeds of
100-120 km/h (62-75 mph), this will save 12%
of fuel.
may not be enough power available to start
the engine.
from losing too much charge and to ensure
that the engine can be started reliably.
Your vehicle is equipped with an intelligent
power management system to control the
distribution of electrical energy. This signifi-
cantly improves reliability when starting the
engine, and also prolongs the useful life of the
battery.
Dynamic power management
While the vehicle is moving, this function dis-
tributes the available power to the various
electrical devices and systems according to
their requirements. The power management
ensures that on-board systems do not con-
sume more electrical power than the alterna-
tor can supply, and thus maintains the maxi-
mum possible battery power level.
Save electrical energy
The engine drives the alternator, thereby
generating electricity. This implies that any
increase in power consumption also increa-
ses fuel consumption! For this reason, switch
off any unneeded electrical devices. Devices
that use a lot of electricity includes the blow-
er at a high setting, the rear window heating
or the seat heating*.
The main functions incorporated in the power
management system are battery diagnosis,
residual current management and dynam-
ic power management.
Note
Battery diagnosis
●
Neither is the power management system
The battery diagnosis function constantly
registers the condition of the battery. Sensors
detect the battery voltage, battery current
and battery temperature. This enables the
system to calculate the current power level
and charge condition of the battery.
able to overcome the given physical limits.
Please remember that the power and use-
ful life of the battery are limited.
Power management
●
When there is a risk that the vehicle will
not start, the alternator power failure or
low battery charge level warning lamp will
be shown page 123.
This system helps to ensure relia-
ble starting
›››
Residual current management
The power management controls the distri-
bution of electrical energy and thus helps to
ensure that there is always enough power
available to start the engine.
The residual current management reduces
power consumption while the vehicle is
parked. It controls the supply of power to the
various electrical devices while the ignition is
switched off. The system takes the battery di-
agnosis data into consideration.
Flat battery
Starting ability has first priority.
If a vehicle with a conventional electrical sys-
tem is left parked for a long time, the battery
will gradually lose its charge because certain
electrical devices, such as the electronic
gearbox lock continues to draw current even
when the ignition is off. In some cases there
Short trips, city traffic and low temperatures
all place a heavy load on the battery. In
these conditions a large amount of power is
consumed, but only a small amount is sup-
plied. The situation is also critical if electrical
devices are in use when the engine is not
Depending on the power level of the battery,
switch off the individual electrical devices
one after the other to prevent the battery
»
261
English 
