Cadillac 2008 DTS Automobile User Manual


 
Battery Load Management
The battery load management feature is designed to
monitor the vehicle’s electrical load and determine
when the battery is in a heavy discharge condition.
During times of high electrical loading, the engine
may idle at a higher revolutions per minute (rpm)
setting than normal to make sure the battery charges.
High electrical loads may occur when several of
the following are on: headlamps, high beams, fog lamps,
rear window defogger, the climate control fan at high
speeds, heated seats and engine cooling fans.
If the battery continues to discharge, even with the
engine idling at a higher rpm setting, some electrical
loads will automatically be reduced. When this occurs,
the rear window defogger may take slightly longer
to clear the glass, the heated seats may not get as
warm as they usually do and the climate control fan
may cut back to a lower speed. For more battery saving
information, see “Battery Saver Active Message”
under DIC Warnings and Messages on page 3-73.
Electric Power Management
The vehicle has Electric Power Management (EPM)
that estimates the battery’s temperature and state
of charge. It then adjusts the voltage for best
performance and extended life of the battery.
When the battery’s state of charge is low, the voltage
is raised slightly to quickly put the charge back in.
When the state of charge is high, the voltage is lowered
slightly to prevent overcharging. If the vehicle has a
voltmeter gage or a voltage display on the Driver
Information Center (DIC), you may see the voltage
move up or down. This is normal. If there is a problem,
an alert will be displayed.
The battery can be discharged at idle if the electrical
loads are very high. This is true for all vehicles.
This is because the generator (alternator) may not
be spinning fast enough at idle to produce all the
power that is needed for very high electrical loads.
A high electrical load occurs when several of the
following loads are on: headlamps, high beams, fog
lamps, rear window defogger, climate control fan at
high speed, heated seats, engine cooling fans, trailer
loads, and loads plugged into accessory power outlets.
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