2008 GMC SIERRA charging

Shifting Out of PARK (P)
This vehicle is equipped with an electronic shift lock
release system. The shift lock release is designed to:
Prevent ignition key removal unless the shift
lever is in PARK (P) with the shift lever button fully
released, and
Prevent movement of the shift lever out of
PARK (P), unless the ignition is in ON/RUN or
ACC/ACCESSORY and the regular brake pedal is
applied.
The shift lock release is always functional except in the
case of an uncharged or low voltage (less than
9 volt) battery.If your vehicle has an uncharged battery or a battery
with low voltage, try charging or jump starting the
battery. SeeJump Starting on page 5-46for more
information.
To shift out of PARK (P) use the following:
1. Apply the brake pedal.
2. Move the shift lever to the desired position.
If you still are unable to shift out of PARK (P):
1. Ease the pressure on the shift lever.
2. While holding down the brake pedal, press the shift
lever all the way into PARK (P).
3. Move the shift lever to the desired position.
If you are still having a problem shifting, then have your
vehicle serviced soon.
2-52

Airbag Readiness Light..................................3-38
Airbag Off Light............................................3-39
Passenger Airbag Status Indicator...................3-41
Charging System Light..................................3-43
Voltmeter Gage............................................3-43
Brake System Warning Light..........................3-44
Antilock Brake System Warning Light...............3-45
StabiliTrak
®Indicator Light..............................3-46
Engine Coolant Temperature Gage..................3-46
Tire Pressure Light.......................................3-47
Malfunction Indicator Lamp.............................3-48
Oil Pressure Gage........................................3-50
Oil Pressure Light.........................................3-51
Security Light...............................................3-52
Fog Lamp Light............................................3-52
Cruise Control Light......................................3-52
Highbeam On Light.......................................3-52
Four-Wheel-Drive Light..................................3-53
Tow/Haul Mode Light....................................3-53
Fuel Gage...................................................3-53
Low Fuel Warning Light.................................3-54Driver Information Center (DIC).......................3-54
DIC Operation and Displays
(With DIC Buttons)....................................3-55
DIC Operation and Displays
(Without DIC Buttons)................................3-60
DIC Warnings and Messages.........................3-63
DIC Vehicle Customization
(With DIC Buttons)....................................3-72
Audio System(s).............................................3-80
Setting the Clock..........................................3-81
Radio(s)......................................................3-84
Using an MP3 (Radio with CD or
Six-Disc CD Player).................................3-102
Using an MP3 (Radio with CD and
DVD Player)...........................................3-106
XM Radio Messages...................................3-111
Navigation/Radio System..............................3-112
Rear Seat Entertainment (RSE) System.........3-113
Rear Seat Audio (RSA)................................3-122
Theft-Deterrent Feature................................3-123
Audio Steering Wheel Controls......................3-124
Radio Reception.........................................3-125
Fixed Mast Antenna....................................3-126
XM™ Satellite Radio Antenna System............3-126
Section 3 Instrument Panel
3-2

Reading Lamps
If your vehicle has reading lamps they are located on
the overhead console.
To turn on the reading lamps, press the button
located next to each lamp. To turn them off, press the
button again.
Your vehicle may also have reading lamps in other
locations. To turn the lamps on or off, press the button
located next to the lamp.
If your vehicle has a DVD Rear Seat Entertainment
(RSE) system, press the lamp lenses to turn the lamps
on or off.
The lamps are xed and cannot be adjusted.
Cargo Lamp
The cargo lamps come on by turning the instrument
panel brightness control knob to the farthest clockwise
position. This knob is located on the instrument
panel and also turns on the dome lamps.
The cargo lamp can be used if more light is needed in
the cargo area of the vehicle or in the top-box
storage units.
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.
3-22

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 3-63.
Battery Run-Down Protection
This feature shuts off the dome and reading lamps, if
they are left on for more than 10 minutes after the
ignition is turned off. The cargo lamp shuts off
after 20 minutes. This prevents 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.
The vehicle may have two accessory power outlets
located below the climate control system, or may have
one accessory power outlet and one cigarette lighter.
The cigarette lighter is designed to t only in the
receptacle closest to the driver.
There may be another accessory power outlet in the
rear cargo area. If the vehicle has a oor console, there
is an accessory power outlet inside the storage bin
and one on the rear of the oor console.
To use an accessory power outlet, remove the protective
cap. When not in use, always cover the accessory
power outlet with the protective cap.
Notice:Leaving electrical equipment plugged in for
an extended period of time while the vehicle is off
will drain the battery. Power is always supplied
to the outlets. Always unplug electrical equipment
when not in use and do not plug in equipment
that exceeds the maximum 20 ampere rating.
3-23

Charging System Light
This light will come on
briey when you turn on
the ignition, but the engine
is not running, as a
check to show you it is
working.
It should go out once the engine is running. If it stays
on, or comes on while you are driving, you may have a
problem with the charging system. A charging system
Driver Information Center (DIC) message may also
appear. SeeDIC Warnings and Messages on page 3-63
for more information. This light could indicate that you
have problems with a generator drive belt, or another
electrical problem. Have it checked right away. If
you must drive a short distance with the light on, be
certain to turn off all your accessories, such as the radio
and air conditioner.
Voltmeter Gage
Your vehicle may have a
voltmeter gage.
When the ignition is on, this gage indicates the battery
voltage.
When the engine is running, this 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. If the vehicle is operating outside
the normal operating range, the charging system light
will come on. SeeCharging System Light on page 3-43
for more information. The voltmeter gage may also
read lower when in fuel economy mode. This is normal.
3-43

Readings outside the normal operating range may also
occur when a large number of electrical accessories
are operating in the vehicle and the engine is left idling
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 readings
outside the normal operating range. If you must
drive, turn off all unnecessary accessories.
Readings outside the normal operating range indicate a
possible problem in the electrical system. Have the
vehicle serviced as soon as possible.Brake System Warning Light
With the ignition on, the brake system warning light
will come on when you set the parking brake. If you
try to drive with the parking brake engaged, a chime
will sound when the vehicle speed is greater
than 5 mph (8 km/h).
Your vehicle’s hydraulic brake system is divided into
two parts. If one part is not working, the other part can
still work and stop you. For good braking, though,
you need both parts working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have your brake system
inspected right away.
This light may also come on due to low brake uid. See
Brakes on page 5-42for more information.
United States
Canada
3-44

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 3-38andAirbag System on page 1-68for 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 3-43. 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 3-44. 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 BRAKES SOON
This message displays if there is a problem with the
brake system. 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. 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 2-63for more information. See
your dealer/retailer for service.
SERVICE STABILITRAK
If your vehicle has StabiliTrak®and this message
displays, it means there may be a problem with the
StabiliTrak
®system. If you see this message, try to reset
the system. Stop; turn off the engine for at least
15 seconds; then start the engine again. If this message
still comes on, it means there is a problem. You
should see your dealer/retailer for service. The vehicle
is safe to drive, however, you do not have the benet
of StabiliTrak
®, so reduce your speed and drive
accordingly.
3-68

Heavy-DutyTrailer Wiring Harness
Package
For vehicles equipped with heavy duty trailering, the
harness is connected to a bracket on the hitch platform.
The seven-wire harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed*
Dark Blue: Trailer Brake**The fuses for these two circuits are installed in the
underhood electrical center, but the wires are not
connected. They should be connected by your dealer or
a qualied service center. The fuse and wire for the
ITBC is factory installed and connected if the vehicle is
equipped with an ITBC. The fuse for the battery
feed is not required if your vehicle has an auxiliary
battery. If your vehicle does not have an auxiliary
battery, have your dealer or authorized service center
install the required fuse.
If you are charging a remote (non-vehicle) battery, press
the tow/haul mode button located at the end of the
shift lever. This will boost the vehicle system voltage and
properly charge the battery. If the trailer is too light for
tow/haul mode, you can turn on the headlamps as
a second way to boost the vehicle system and charge
the battery.
4-91