2008 GMC YUKON DENALI auxiliary 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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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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Battery Replacement
To change the remote control batteries, do the following:
1. Slide the rear cover back on the remote control.
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 cover.
If the remote control is to be stored for a long period of
time, remove the battery and keep it in a cool, dry place.
Problem Recommended Action
No power. The ignition might not be
turned ON/RUN or in
ACC/ACCESSORY.
The picture does not ll the
screen. There are black
borders on the top and
bottom or on both sides or
it looks stretched out.Check the display mode
settings in the setup menu
by pressing the display
menu button on the remote
control.
In auxiliary mode, the
picture moves or scrolls.Check the auxiliary input
connections at both
devices.
Problem Recommended Action
The remote control does
not work.Check to make sure there
is no obstruction between
the remote control and the
transmitter window.
Check the batteries to
make sure they are not
dead or installed
incorrectly.
After stopping the player,
I push Play but sometimes
the DVD starts where I left
off and sometimes at the
beginning.If the stop button was
pressed one time, the
DVD player resumes
playing where the DVD
was stopped. If the stop
button was pressed two
times the DVD player
begins to play from the
beginning of the DVD.
The auxiliary source is
running but there is no
picture or sound.Check that the RSE video
screen is in the auxiliary
source mode.
Check the auxiliary input
connections at both
devices.
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Fuses Usage
47 Power Take-Off
48Auxiliary Climate Control (Ignition),
Compass-Temperature Mirror
49Center High-Mounted Stoplamp
(CHMSL)
50 Rear Defogger
51 Heated Mirrors
52 SEO B1 Uptter Usage (Battery)
53Cigarette Lighter, Auxiliary Power
Outlet
54Automatic Level Control Compressor
Relay, SEO Uptter Usage
55 Climate Controls (Ignition)
56Engine Control Module, Secondary
Fuel Pump (Ignition)
J-Case Fuses Usage
60 Cooling Fan 1
61 Automatic Level Control Compressor
62 Heavy Duty Antilock Brake System
63 Cooling Fan 2
64 Antilock Brake System 1
65 Starter
66 Stud 2 (Trailer Brakes)
67 Left Bussed Electrical Center 1
J-Case Fuses Usage
68 Electric Running Boards
69 Heated Windshield Washer System
70 Not Used
71Stud 1 (Trailer Connector
Battery Power)
72 Mid-Bussed Electrical Center 1
73 Climate Control Blower
74 Power Liftgate Module
75 Left Bussed Electrical Center 2
Relays Usage
FAN HI Cooling Fan High Speed
FAN LO Cooling Fan Low Speed
ENG EXH VLV Not Used
FAN CNTRL Cooling Fan Control
HDLP LO/HID Low-Beam Headlamps
FOG LAMP Front Fog Lamps
A/C CMPRSR Air Conditioning Compressor
STRTR Starter
PWR/TRN Powertrain
FUEL PMP Fuel Pump
PRK LAMP Parking Lamps
REAR DEFOG Rear Defogger
RUN/CRANK Switched Power
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