2008 GMC ACADIA battery

Reading Lamps
The vehicle has reading lamps that also act as the
dome lamp. Press the button to turn them on and 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 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.
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 or Service Battery Charging System. If this
message is displayed, it is recommended that the
driver reduce the electrical loads as much as possible.
SeeDIC Warnings and Messages on page 3-66.
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Battery Run-Down Protection
This vehicle has a feature to help 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 will 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 timeout after 10 minutes, if they
are manually turned on before the ignition is off.
Head-Up Display (HUD)
{CAUTION:
If the HUD image is too bright or too high in
your eld of view, it may take you more time
to see things you need to see when it is dark
outside. Be sure to keep the HUD image dim
and placed low in your eld of view.
If the vehicle has the Head-Up Display (HUD),
some information concerning the operation of the
vehicle is projected onto the windshield. This includes
the speedometer reading, RPM reading, transmission
position, outside air temperature, the tap shift gear,
and a brief display of the current radio station,
including XM information or CD track. It will also
display turn-by-turn navigation information if the
vehicle has a navigation radio. The images are
projected by the HUD lens located on the driver’s
side of the instrument panel.
The tap shift gear will also appear on the HUD if
the vehicle has tap shift and it is active.
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If You Cannot See the HUD Image
When the Ignition Is On
Is anything covering the HUD lens?
Is the HUD dimmer setting bright enough?
Is the HUD image adjusted to the proper height?
Are you wearing polarized sunglasses?
Still no HUD image? Check the fuse in the
instrument panel fuse block. SeeInstrument
Panel Fuse Block on page 5-100.
If the HUD Image Is Not Clear
Is the HUD image too bright?
Are the windshield and HUD lens clean?
If the HUD image is not correct, contact your
dealer/retailer.
Keep in mind that the windshield is part of the
HUD system.
Accessory Power Outlet(s)
The accessory power outlets can be used to connect
electrical equipment such as a cellular phone or
CB radio.
Your vehicle may have four accessory power outlets.
They are located on the instrument panel below
the climate controls, inside the front center console
storage bin, at the rear of the center console, and in
the rear cargo area.
To use the outlets, remove the cover. When not in
use, always cover the outlet with the protective cap.
Notice:Leaving electrical equipment on for
extended periods will drain the battery. Always
turn off electrical equipment when not in use
and do not plug in equipment that exceeds the
maximum amperage rating of 20 amperes.
3-24

Voltmeter Gage
When the engine is not
running, but the ignition
is turned on, this gage
shows the battery’s state
of charge in DC volts.
When the engine is running, this gage shows the
condition of the charging system. The vehicle’s
charging system regulates voltage based on the state
of charge of the battery. The voltmeter may uctuate.
This is normal. Readings between the low and high
warning zones indicate the normal operating range.Readings in the low warning zone may occur when a
large number of electrical accessories are operating
in the vehicle and the engine is left idling for an
extended period.
If there is a problem with the battery charging system,
a SERVICE BATTERY CHARGING SYSTEM message
will appear in the Driver Information Center (DIC)
and/or the charging system light will come on. See
DIC Warnings and Messages on page 3-66and
Charging System Light on page 3-45for more
information.
However, readings in either warning zone may
indicate a possible problem in the electrical system.
Have the vehicle serviced as soon as possible.
3-46

Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
SeeGasoline Octane on page 5-6. Poor fuel quality
causes the engine not to run as efficiently as
designed. You might notice this as stalling after
start-up, stalling when you put the vehicle into gear,
misring, hesitation on acceleration, or stumbling
on acceleration — these conditions might go away
once the engine is warmed up. This will be detected
by the system and cause the light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn
off, your dealer/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have
or might begin programs to inspect the emission
control equipment on your vehicle. Failure to pass
this inspection could prevent you from getting a
vehicle registration.
Here are some things you need to know to help
your vehicle pass an inspection:
Your vehicle will not pass this inspection if the
check engine light is on or not working properly.
Your vehicle will not pass this inspection if the
OBD (on-board diagnostic) system determines that
critical emission control systems have not been
completely diagnosed by the system. The vehicle
would be considered not ready for inspection.
This can happen if you have recently replaced the
battery or if the battery has run down. The diagnostic
system is designed to evaluate critical emission
control systems during normal driving. This can take
several days of routine driving. If you have done this
and your vehicle still does not pass the inspection
for lack of OBD system readiness, your dealer/retailer
can prepare the vehicle for inspection.
3-53

BATTERY SAVER ACTIVE
This message displays when the system detects
that the battery voltage is dropping below expected
levels. The battery saver system starts reducing
certain features of the vehicle that you may be able
to notice. At the point that the features are disabled,
this message is displayed. It means that the vehicle
is trying to save the charge in the battery.
Turn off all unnecessary accessories to allow the
battery to recharge.
The normal battery voltage range is 11.5 to 15.5 volts.
CHANGE ENGINE OIL SOON
This message displays when the engine oil needs to
be changed. When you change the engine oil, be sure
to reset the CHANGE ENGINE OIL SOON message.
SeeEngine Oil Life System on page 5-18for information
on how to reset the message. SeeEngine Oil on
page 5-15andScheduled Maintenance on page 6-4
for more information.
CHECK TIRE PRESSURE
This message displays when the pressure in one or
more of the vehicle’s tires needs to be checked.
This message also displays LEFT FRONT, RIGHT
FRONT, LEFT REAR, or RIGHT REAR to indicate
which tire needs to be checked. You can receive more
than one tire pressure message at a time. To read
the other messages that may have been sent at
the same time, press the set/reset button or the trip
odometer reset stem. If a tire pressure message
appears on the DIC, stop as soon as you can. Have
the tire pressures checked and set to those shown
on the Tire Loading Information label. SeeTires
on page 5-48,Loading Your Vehicle on page 4-21,
andInflation - Tire Pressure on page 5-55. The DIC
also shows the tire pressure values. See “DIC Operation
and Displays (With DIC Buttons)” earlier in this section.
If the tire pressure is low, the low tire pressure
warning light comes on. SeeTire Pressure Light
on page 3-50.
CRUISE SET TO XXX
This message displays whenever the cruise control
is set. SeeCruise Control on page 3-12for more
information.
3-67

PARK ASSIST OFF
If your vehicle has the Ultrasonic Rear Parking
Assist (URPA) system, after the vehicle has been
started and shifted out of PARK (P), this message
displays to remind the driver that the URPA system
has been turned off. Press the set/reset button or
the trip odometer reset stem to acknowledge this
message and clear it from the DIC display. To turn
the URPA system back on, seeUltrasonic Rear
Parking Assist (URPA) on page 2-45.
PASSENGER DOOR OPEN
This message displays and a chime sounds if the
passenger door is not fully closed and the vehicle is
in a drive gear. Stop and turn off the vehicle, check
the door for obstructions, and close the door again.
Check to see if the message still appears on the DIC.
REMOTE KEY LEARNING ACTIVE
This message displays while you are matching a
Remote Keyless Entry (RKE) transmitter to your vehicle.
See “Matching Transmitter(s) to Your Vehicle” under
Remote Keyless Entry (RKE) System Operation on
page 2-5andDIC Operation and Displays (With DIC
Buttons) on page 3-57orDIC Operation and Displays
(Without DIC Buttons) on page 3-63for more information.
REPLACE BATTERY IN REMOTE KEY
This message displays if a Remote Keyless Entry (RKE)
transmitter battery is low. The battery needs to be
replaced in the transmitter. See “Battery Replacement”
underRemote Keyless Entry (RKE) System Operation
on page 2-5.
RIGHT REAR DOOR OPEN
This message displays and a chime sounds if the
passenger side rear door is not fully closed and the
vehicle is in a drive gear. Stop and turn off the vehicle,
check the door for obstructions, and close the door
again. Check to see if the message still appears
on the DIC.
SERVICE A/C (Air Conditioning)
SYSTEM
This message displays when the electronic sensors
that control the air conditioning and heating systems
are no longer working. Have the climate control
system serviced by your dealer/retailer if you notice
a drop in heating and air conditioning efficiency.
3-71

SERVICE AIR BAG
This message displays if there is a problem with the
airbag system. Have your dealer/retailer inspect
the system for problems. SeeAirbag Readiness Light
on page 3-42andAirbag System on page 1-61for
more information.
SERVICE ALL WHEEL DRIVE
If your vehicle has the All-Wheel Drive (AWD) system,
this message displays if there is a problem with this
system. If this message appears, stop as soon as
possible and turn off the vehicle. Restart the vehicle
after 30 seconds and check for the message on the
DIC display. If the message is still displayed or appears
again when you begin driving, the AWD system
needs service. See your dealer/retailer.
SERVICE BATTERY CHARGING
SYSTEM
On some vehicles, this message displays if there is a
problem with the battery charging system. Under certain
conditions, the charging system light may also turn
on in the instrument panel cluster. SeeCharging System
Light on page 3-45. Driving with this problem could
drain the battery. Turn off all unnecessary accessories.
Have the electrical system checked as soon as
possible. See your dealer/retailer.
SERVICE BRAKE SYSTEM
This message displays along with the brake system
warning light if there is a problem with the brake system.
SeeBrake System Warning Light on page 3-47. If this
message appears, stop as soon as possible and turn
off the vehicle. Restart the vehicle and check for
the message on the DIC display. If the message is
still displayed or appears again when you begin driving,
the brake system needs service as soon as possible.
See your dealer/retailer.
SERVICE PARK ASSIST
If your vehicle has the Ultrasonic Rear Parking Assist
(URPA) system, this message displays if there is a
problem with the URPA system. Do not use this
system to help you park. SeeUltrasonic Rear Parking
Assist (URPA) on page 2-45for more information.
See your dealer/retailer for service.
SERVICE POWER STEERING
This message displays when a problem is detected
with the power steering system. When this message
is displayed, you may notice that the effort required to
steer the vehicle increases or feels heavier, but you
will still be able to steer the vehicle. Have your vehicle
serviced by your dealer/retailer immediately.
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