148 Intelligent technology
Battery diagnosi s
Battery diagnosis continuously determines
the state of the battery. Sensors determine
battery voltage, battery current and battery
temperature. This determines the current
state of charge and the power of the battery.
Idling current management
I dling current management reduces energy
consumption while the vehicle is standing.
With the ignition switched off, it controls the
energy supply to the various electrical compo
nents. Data from battery diagnosis is consid
ered.
Depending on the battery's state of charge,
individual consumers are gradually turned off
to prevent excessive discharge of the battery
and thus maintain starting capability.
Dynamic energy management
While the vehicle is being driven, dynamic en
ergy management distributes the energy gen
erated according to the needs of the individu
al components. It regulates consumption, so
that more electrical energy is not being used
than is being generated and ensures an opti
mal state of charge for the battery .
(D Tips
-But even energy management cannot
negate the limits of physics. Consider
that the power and life of a battery are
limited .
- If starting ability is threatened, you are informed by a warning
~page 149,
Driver notification in the instrument
cluster display.
What you should know
The highest priority is given to maintaining
starting capability .
The battery is severely taxed in short -distance
driving, in city traffic and during the cold time
of year. Abundant electrical energy is re
quired, but only a little is generated.
It is also
critical if the engine is not running and electri- cal components are turned on.
In this in
stance energy is being consumed but none is
being generated.
It is in precisely these situations that you will
notice energy management actively regulat
ing the distribution of energy.
Vehicle stands for an extended period
If you do not drive your vehicle over a period
of several days or weeks , electrical compo
nents are gradually cut back or switched off .
This reduces energy consumption and main
tains starting capability over a longer period.
Take into consideration that when you unlock
your vehicle, some convenience functions ,
such as the remote key or power seat adjust
ment, may not be available. The convenience
functions will be available again when you
turn on the ignition and start the engine.
With the engine turned off
If you listen to the radio, for example, with
the engine turned off, the battery is being dis
charged.
If starting capability is jeopardized due to en
ergy consumption, a message appears in the
driver information display.
You have to start the engine to charge the
battery.
With the engine running
Although electrical energy is generated when
the vehicle is being driven, the battery can be
come discharged. This happens mostly when
little energy is being generated and a great
deal consumed and the battery's state of
charge is not optimal.
To bring the energy balance back into equili
brium, consumers which require especially
large amounts of energy are temporarily cut
back or switched off . Heating systems in par
ticular require a great deal of energy. If you
notice, for example, that the heated seats* or
the heated rear window are not heating, they
have been temporarily cut back or switched .,.
