154 Int e llig e nt t echnolog y
Batt ery diagnosis
Battery d iagnosis continuously determ ines
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
Idling current management reduces energy
consumption while the vehicle is standing.
With the ignition switched off, it contro ls the
energy supply to the various e lectrica l compo-
nents. Data from battery diagnosis is consid-
ered.
Depending on the battery's state of charge,
individua l consumers are gradually t urned off
to prevent excess ive d ischarge of the battery
and thus maintain start ing 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-
a l components. It regu lates 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 lim its of physics. Consider
that the power and life of a battery are
limited .
- If starting ab ility is threatened, you are
informed by a warn ing
~ page 155,
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 e lectr ica l energy is re-
q uired, but only a litt le is gene rated.
It is also
crit ica l if the engine is not running and elect ri-
cal components are turned on. In this in-
stance energy is being consumed but none is
being generated.
It is in prec ise ly these s ituations that you will
notice energy management active ly regu lat -
ing the distribution of energy.
Vehicle stands for an extend ed period
If you do no t d rive your vehicle over a period
of seve ral days or weeks , e lectr ical compo-
nents are gradually cut back or sw itched off.
This reduces energy consumption and main-
tains starting capability over a longer pe riod.
Take into consideration that whe n you unlock
yo ur vehicle, some conven ience 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 ign ition and start the engine.
With the engine turn ed off
If you listen to the radio, for examp le, with
the engine t urned off, the battery is being dis-
charged .
If starting capab ility is jeopard ized d ue 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 d ischarged. This happens mostly when
little energy is being gene rated and a g reat
deal consumed and the battery's state of
charge is not optimal.
To bring the energy ba la nce back into equili-
brium, consumers which req uire espec ially
large amounts of energy are temporar ily cut
back or sw itched off. Heating systems in par-
ticular require a great deal of energy . If you
not ice, for examp le, that the heated seats* or
the heated rear window are not heating, they
have been temporarily cut back or switched .,.
To Next Page
Loading...
