Reading Lamps; Electric Power Management - Cadillac CTS-V 2009 Owner's Manual

Reading Lamps

The reading lamps are located on the overhead console.
These lamps come on automatically when any door is
opened.
For manual operation, press the button next to each
lamp to turn it on or off.
If the reading lamps are left on, they automatically shut
off 10 minutes after the ignition has been turned off.

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: 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 3-58.
3-21