2005 GMC SIERRA charging

Battery Warning Light
If this light is displayed
when the engine is
running, you may have a
problem with your charging
system.
The battery display will also stay on while the key is in
RUN until the engine is started.
If the light stays on after starting the engine it could
indicate a problem with the generator drive belt, or some
other charging system problem. Have it checked right
away. Driving with this light displayed could drain
your battery.
If you must drive a short distance with this light
displayed, it helps to turn off all your accessories, such
as the radio and the air conditioner.
Voltmeter Gage
When your engine is not
running, but the ignition is
in RUN, this gage
shows your 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. The voltmeter gage may also read lower when in
fuel economy mode. This is normal.
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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.
Up-Shift Light (Manual
Transmission)
This light is used on some
models with manual
transmissions.The shift indicator light will show you when to shift to
the next highest gear, and will help you get the best
fuel economy.
Brake System Warning Light
With the ignition on, the brake system warning light will
ash when you set the parking brake. The light will ash if
the parking brake doesn’t release fully. If you try to drive
with the parking brake engaged, a chime will sound when
the vehicle speed is greater than 3 mph (5 km/h).
Your vehicle’s hydraulic brake system is divided into
two parts. If one part isn’t working, the other part can still
work and stop you. For good braking, though, you
need both parts working well.
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DIC Warnings and Messages
Warning messages are displayed on the Driver
Information Center (DIC) to notify the driver that the
status of the vehicle has changed and that some action
may be needed by the driver to correct the condition.
If there is more than one message that needs to
be displayed, they will appear one after another. Some
messages may not require immediate action, but
you should press any of the four DIC buttons on the
steering wheel, if equipped, to acknowledge that
you received the messages and clear them from the
display. If your vehicle is not equipped with DIC buttons
on the steering wheel, press the trip odometer reset
stem located on the instrument panel cluster to
acknowledge messages and clear them from the display.
Some messages cannot be cleared from the display
because they are more urgent. These messages require
action before they can be removed from the DIC
display. You should take any messages that appear on
the display seriously and remember that clearing the
messages will only make the messages disappear, not
correct the problem.
The following are the possible messages that can be
displayed and some information about them.
BATTERY NOT CHARGING
On some vehicles, if the battery is not charging during
operation, this message will appear on the DIC.
Driving with this problem could drain your battery. Have
the electrical system checked by your GM dealer as
soon as possible. Pressing any of the four DIC buttons,
if equipped, will acknowledge the message and clear
it from the DIC display. If your vehicle is not equipped
with the four DIC buttons, pressing the trip odometer
reset stem will acknowledge the message and clear it
from the DIC display. SeeBattery Warning Light
on page 3-38andVoltmeter Gage on page 3-38.
BUCKLE PASSENGER
If your vehicle is equipped with the passenger sensing
system, this message reminds you to buckle the
passenger’s seat belt. SeePassenger Sensing System
on page 1-76.
This message will display and a chime will sound when
the ignition is on, the driver’s seat belt is buckled, the
passenger’s seat belt is unbuckled with the passenger
airbag enabled and the vehicle is in motion. You should
have the passenger buckle their seat belt.
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This reminder will be repeated if the ignition is on, the
vehicle is in motion, the driver is buckled and the
passenger is still unbuckled and the passenger airbag is
enabled. If the passenger’s seat belt is already
buckled, this message and chime will not come on.
Pressing any of the four DIC buttons, if equipped, will
acknowledge the message and clear it from the
DIC display. If your vehicle is not equipped with the
four DIC buttons, pressing the trip odometer reset stem
will acknowledge the message and clear it from the
DIC display.
BUCKLE SEATBELT
If your vehicle is equipped with the passenger sensing
system, this message reminds you to buckle the
driver’s seat belt. SeePassenger Sensing System on
page 1-76.
This message will display and a chime will sound when
the ignition is on, the driver’s seat belt is unbuckled
and the vehicle is in motion. You should buckle
your seat belt.
If the driver remains unbuckled when the ignition is on
and the vehicle is in motion, the reminder will be
repeated. If the driver’s seat belt is already buckled, this
message and chime will not come on.This message is an additional reminder to the Safety
Belt Reminder Light in the instrument panel cluster.
SeeSafety Belt Reminder Light on page 3-33for more
information.
Pressing any of the four DIC buttons, if equipped, will
acknowledge the message and clear it from the
DIC display. If your vehicle is not equipped with the
four DIC buttons, pressing the trip odometer reset stem
will acknowledge the message and clear it from the
DIC display.
CHARGING SYSTEM FAILURE
On some vehicles, if there is a problem with the
generator and battery charging system, this message
will appear on the DIC, a chime will sound and the
battery warning light on the instrument panel cluster will
come on. Driving with this problem could drain your
battery. Turn off all unnecessary accessories. Stop and
turn off the vehicle as soon as it is safe to do so.
Have the electrical system checked by your GM dealer
immediately. SeeBattery Warning Light on page 3-38
andVoltmeter Gage on page 3-38for more information.
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SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will be displayed on the DIC. 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 GM dealer.
SERVICE CHARGING SYSTEM
On some vehicles, if there is a problem with the battery
charging system, this message will appear on the
DIC. Under certain conditions, the battery warning light
may also turn on in the instrument panel cluster.
SeeBattery Warning Light on page 3-38. The battery
will not be charging at an optimal rate and the vehicle
will lose the ability to enter the fuel economy mode. The
vehicle is safe to drive, however you should have the
electrical system checked by your GM dealer. Pressing
any of the four DIC buttons, if equipped, will
acknowledge the message and clear it from the DIC
display. If your vehicle is not equipped with the four DIC
buttons, pressing the trip odometer reset stem will
acknowledge the message and clear it from the DIC
display.
SERVICE RIDE CONTROL
If a problem occurs with the suspension system, this
message will appear on the DIC. If this message
appears, stop 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 air suspension system
needs service. See your GM dealer.
TIGHTEN FUEL CAP
If the vehicle’s fuel cap is not tightened properly, this
message may appear along with the check engine light
on the instrument panel. SeeMalfunction Indicator
Lamp on page 3-44. Fully reinstall the fuel cap.
SeeFilling Your Tank on page 5-10. The diagnostic
system can determine if the fuel cap has been left off or
improperly installed. A loose or missing fuel cap will
allow fuel to evaporate into the atmosphere. A few
driving trips with the cap properly installed should turn
the light and message off.
TRACTION ACTIVE
When the traction control system had detected that any
of the vehicle’s wheels are slipping, the traction
control system will activate and this message will appear
on the DIC. For more information, seeTraction Assist
System (TAS) on page 4-8.
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Heavy-DutyTrailer Wiring Harness
Package
For vehicles equipped with heavy duty trailering, the
harness is connected to the trailer plug mounted to the
hitch platform.The eight-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
Light Blue: CHMSL*
Red: Battery Feed**
Dark Blue: Trailer Brake
* The Center High-Mounted Stoplamp (CHMSL) wire is
tied next to the trailer wiring harness for use with a
trailer, slide-in camper or cap.
**If your vehicle is charging a remote (non-vehicle)
battery, turn on the headlamps to boost the vehicle
system voltage and properly charge the battery.
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