2008 GMC YUKON DENALI battery

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. See
DIC Warnings and Messages on page 3-56.Battery Run-Down Protection
This feature shuts off the dome, and reading lamps
if they are left on for more than 10 minutes when
the ignition is off. This will keep the battery from
running down.
Accessory Power Outlet(s)
Accessory power outlets can be used to connect
auxiliary electrical equipment, such as a cellular
telephone or CB radio.
There are two under the climate controls, one inside the
center oor console, one on the rear of the center
oor console and one accessory power outlet in the rear
cargo area on the passenger side.
To use an accessory power outlet, remove the protective
cap. When not in use, always cover the accessory
power outlet with the protective cap.
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The accessory power outlets are powered, even with
the ignition off. Continuing to use accessory power
outlets while the ignition is in LOCK/OFF may cause the
vehicle’s battery to run down.
Notice:If electrical devices are left plugged into a
power outlet, the battery may drain causing your
vehicle not to start or damage to the battery.
This would not be covered by the warranty. Always
unplug all electrical devices when turning off
your vehicle.
Certain accessory plugs may not be compatible to the
accessory power outlet and could result in blown
adapter or vehicle fuses. If you experience a problem,
see your dealer/retailer for additional information on
the accessory power plugs.
Notice:Adding any electrical equipment to your
vehicle may damage it or keep other components
from working as they should. The repairs would not
be covered by your warranty. Do not use equipment
exceeding maximum amperage rating of 20 amperes.
Check with your dealer/retailer before adding
electrical equipment.
When adding electrical equipment, be sure to follow the
proper installation instructions included with the
equipment. Do not use equipment exceeding the
maximum amperage rating of 20 amperes.Notice:Improper use of the power outlet can cause
damage not covered by your warranty. Do not
hang any type of accessory or accessory bracket
from the plug because the power outlets are
designed for accessory power plugs only.
Ashtray(s) and Cigarette Lighter
The front ashtray is located near the center of the
instrument panel or on the front console, if equipped.
Pull on the ashtray door to open it.
Notice:If you put papers, pins, or other ammable
items in the ashtray, hot cigarettes or other
smoking materials could ignite them and possibly
damage your vehicle. Never put ammable items in
the ashtray.
To remove the front ashtray pull the ashtray up.
To use the cigarette lighter, push it in all the way, and
let go. When it’s ready, it will pop back out by itself.
Notice:Holding a cigarette lighter in while it
is heating does not let the lighter back away from
the heating element when it is hot. Damage from
overheating can occur to the lighter or heating
element, or a fuse could be blown. Do not hold a
cigarette lighter in while it is heating.
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Voltmeter Gage
When your engine is not
running, but the ignition is
on, this gage shows
the battery’s state of
charge in DC volts.
When the engine is running, the gage shows the
condition of the charging system. The gage may
transition from a higher to lower or a lower to higher
reading, 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 at an idle for an
extended period. This condition is normal since the
charging system is not able to provide full power
at engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
You can only drive for a short time with the reading
in either warning zone. If you must drive, turn off
all unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
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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.
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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 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 3-34andAirbag System on page 1-75for more
information.
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 3-37. 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 3-39. 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.
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WASHER FLUID LOW ADD FLUID
This message displays when the windshield washer
uid is low. Fill the windshield washer uid reservoir as
soon as possible. SeeEngine Compartment Overview
on page 5-12for the location of the windshield
washer uid reservoir. Also, seeWindshield Washer
Fluid on page 5-35for more information.
DIC Vehicle Customization (With
DIC Buttons)
Your vehicle may have customization capabilities that
allow you to program certain features to one preferred
setting. Customization features can only be programmed
to one setting on the vehicle and cannot be programmed
to a preferred setting for two different drivers.
All of the customization options may not be available on
your vehicle. Only the options available will be
displayed on the DIC.
The default settings for the customization features were
set when your vehicle left the factory, but may have
been changed from their default state since then.
The customization preferences are automatically
recalled.
To change customization preferences, use the following
procedure.
Entering the Feature Settings Menu
1. Turn the ignition on and place the vehicle in
PARK (P).
To avoid excessive drain on the battery, it is
recommended that the headlamps are turned off.
2. Press the customization button to scroll through the
available customizable options.
Feature Settings Menu Items
The following are customization features that allow you
to program settings to the vehicle:
DISPLAY IN ENGLISH
This feature will only display if a language other than
English has been set. This feature allows you to change
the language in which the DIC messages appear to
English.
Press the customization button until the PRESS
VTO
DISPLAY IN ENGLISH screen appears on the DIC
display. Press the set/reset button once to display all
DIC messages in English.
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Drivers are encouraged to set up any auxiliary device
while the vehicle is in PARK (P). SeeDefensive Driving
on page 4-2for more information on driver distraction.
To use a portable audio player, connect a 3.5 mm
(1/8 inch) cable to the radio’s front auxiliary input jack.
When a device is connected, press the radio CD/AUX
button to begin playing audio from the device over
the vehicle speakers.
For optimal sound quality, increase the portable audio
device’s volume to the loudest level.
It is always best to power your portable audio device
through its own battery while playing.
O(Power/Volume):Turn clockwise or
counterclockwise to increase or decrease the volume of
the portable player. Additional volume adjustments
might have to be made from the portable device if the
volume is not loud or soft enough.
BAND:Press to listen to the radio when a portable
audio device is playing. The portable audio device
continues playing, so you might want to stop it or turn
it off.CD/AUX (CD/Auxiliary):Press to play a CD when a
portable audio device is playing. Press again and
the system begins playing audio from the connected
portable audio player. If a portable audio player is
not connected, “No Input Device Found” displays.
DVD/CD AUX (CD/Auxiliary):Press to cycle through
DVD, CD, or Auxiliary when listening to the radio.
The DVD/CD text label and a message showing track or
chapter number displays when a disc is in either slot.
Press again and the system automatically searches
for an auxiliary input device, such as a portable audio
player. If a portable audio player is not connected,
“No Aux Input Device” displays. If a disc is in both the
DVD slot and the CD slot the DVD/CD AUX button
cycles between the two sources and not indicate “No
Aux Input Device”. If a front auxiliary device is
connected, the DVD/CD AUX button cycles through all
available options, such as: DVD slot, CD slot, Front
Auxiliary, and Rear Auxiliary (if available). See “Using
the Auxiliary Input Jack(s)” later in this section, or
“Audio/Video (A/V) Jacks” under,Rear Seat
Entertainment (RSE) System on page 3-105for more
information.
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Push the power button to turn on the headphones.
An indicator light located on the headphones comes on.
If the light comes on but, there is intermittent sound
and/or static on the headphones, or if the indicator light
does not come on, the batteries might need to be
replaced. See “Battery Replacement” later in this section
for more information. Switch the headphones to Off
when not in use.
Infrared transmitters are located at the rear of the RSE
overhead console. The headphones shut off
automatically to save the battery power if the RSE
system and RSA are shut off or if the headphones are
out of range of the transmitters for more than
three minutes. If you move too far forward or step out of
the vehicle, the headphones lose the audio signal.
The headphones automatically turn off after four hours
of continuous use.
To adjust the volume on the headphones, use the
volume control located on the right side.
For optimal audio performance, the headphones must
be worn correctly. The symbol L (Left) appears on
the upper left side, above the ear pad and should be
positioned on the left ear. The symbol R (Right) appears
on the upper right side, above the ear pad and should
be positioned on the right ear.Notice:Do not store the headphones in heat or
direct sunlight. This could damage the headphones
and repairs will not be covered by your warranty.
Storage in extreme cold can weaken the batteries.
Keep the headphones stored in a cool, dry place.
If the foam ear pads attached to the headphones
become worn or damaged, the pads can be replaced
separately from the headphone set. Refer to your
dealer/retailer for more information.
Battery Replacement
To change the batteries on the headphones, do the
following:
1. Turn the screw to loosen the battery door located
on the left side of the headphones. Slide the
battery door open.
2. Replace the two batteries in the compartment.
Make sure that they are installed correctly, using
the diagram on the inside of the battery
compartment.
3. Replace the battery door and tighten the
door screw.
If the headphones are to be stored for a long period of
time, remove the batteries and keep them in a cool,
dry place.
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