Buick 2008 Automobile User Manual


 
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 bring the charge back up. 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 are on, such as: 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.
EPM works to prevent excessive discharge of the battery.
It does this by balancing the generator’s output and the
vehicle’s electrical needs. It can increase engine idle
speed to generate more power, whenever needed.
It can temporarily reduce the power demands of some
accessories.
Normally, these actions occur in steps or levels, without
being noticeable. In rare cases at the highest levels of
corrective action, this action may be noticeable to the
driver. If so, a Driver Information Center (DIC) message
might be displayed, such as BATTERY SAVER ACTIVE,
BATTERY VOLTAGE LOW, or LOW BATTERY. If this
message is displayed, it is recommended that the driver
reduce the electrical loads as much as possible. See DIC
Warnings and Messages on page 3-56.
Inadvertent Power Battery Saver
This feature is designed to protect your vehicle’s battery
against drainage from the interior lamps, or garage door
opener. When the ignition is turned off, the power to
these features will automatically turn off after 10 minutes.
Power will be restored for an additional 10 minutes if any
door is opened, the trunk is opened or the courtesy lamp
switch is turned on.
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