Black plate (8,1)Chevrolet Impala Owner Manual - 2012
6-8 Lighting
Battery Load
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 gauge 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 fastenough 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 bedisplayed, such as BATTERY
SAVER ACTIVE. If this messages
displays, it is recommended that the
driver reduce the electrical loads as
much as possible. See
Driver
Information Center (DIC) on
page 5‑24.
Battery Power Protection
This feature helps prevent the
battery from being drained, if the
interior courtesy lamps, reading/map
lamps, visor vanity lamps, or trunk
lamp are accidentally left on. If any
of these lamps are left on, they
automatically turn off after
10 minutes, if the ignition is off. The
lamps will not come back on again
until one of the following occurs:
.The ignition is turned on.
.The exterior lamps control is
turned off, then on again.
The headlamps will time out after
10 minutes, if they are manually
turned on with the ignition on or off.
