Lighting features, Entry/exit lighting, Battery load management – GMC 2012 Savana User Manual
Page 169: Battery power protection, Lighting features -7, General
Black plate (7,1)
GMC Savana Owner Manual - 2012 - 2nd - 11/11/11
Lighting
6-7
Lighting Features
Entry/Exit Lighting
The vehicle has an illuminated
entry/exit feature.
The dome lamps come on if the
E
DOME OFF button is in the
extended position, when a door is
opened or the key is removed from
the ignition.
Battery Load
Management
The vehicle may have 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 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 SERVICE
BATTERY CHARGING SYSTEM.
If this messages displays, it is
recommended that the driver reduce
the electrical loads as much as
possible. See Battery Voltage and
Charging Messages on page 5‑34.
Battery Power Protection
This feature shuts off the dome
lamps if they are left on for more
than 10 minutes when the ignition is
in LOCK/OFF. This helps to prevent
the battery from running down.