2007 GMC SIERRA CLASSIC charging

Battery Warning Light
If this light comes on
when the engine is
running, there could be
a problem with the
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 while this light
is on could drain the battery.
If you must drive a short distance with this light
on, it helps to turn off all your accessories, such as
the radio and the air conditioner.
Voltmeter Gage
When the engine is not
running, but the ignition
is in RUN, this gage
shows your battery’s
state of charge in
DC volts.
While 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. 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.
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.
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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)
Your vehicle may have
an up-shift light.
It will come on when you should shift to the next
highest gear. It will help the vehicle 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 does not
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 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.
United StatesCanada
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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 to acknowledge that you received
the messages and to clear them from the
display. If your vehicle does not have 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 the
battery. Have the electrical system checked
by your dealer as soon as possible. Pressing any
of the four DIC buttons will acknowledge the
message and clear it from the DIC display. If your
vehicle does not have 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 253andVoltmeter Gage on page 253.
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CHANGE ENGINE OIL
This message is displayed when the engine oil
needs to be changed.
When you change the engine oil, be sure to reset
the CHANGE ENGINE OIL message. See
Engine Oil Life System (Gasoline Engine) on
page 489,Engine Oil (Gasoline Engine) on
page 486, andScheduled Maintenance (Gasoline
Engine) on page 617for more information.
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 the 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 dealer
immediately. SeeBattery Warning Light on
page 253andVoltmeter Gage on page 253for
more information.
CHECK OIL LEVEL
If your vehicle has an oil level sensor, and the oil
level in the vehicle is low, this message will
appear on the DIC. Check the oil level and correct
it as necessary. You may need to let the vehicle
cool or warm up and cycle the ignition to be
sure this message will clear. Once the problem is
corrected, pressing any of the four DIC buttons
will acknowledge the message and clear it from the
DIC display. If your vehicle does not have the
four DIC buttons, pressing the trip odometer reset
stem will acknowledge the message and clear
it from the DIC display. SeeEngine Oil (Gasoline
Engine) on page 486for additional information.
CHECK WASHER FLUID
If the washer uid level is low, this message will
appear on the DIC. SeeWindshield Washer
Fluid on page 516. Adding washer uid to the
windshield washer reservoir will clear the
message. Pressing any of the four DIC buttons
will acknowledge the message and clear it from the
DIC display. If your vehicle does not have the
four DIC buttons, pressing the trip odometer reset
stem will acknowledge the message and clear
it from the DIC display.
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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 253. 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 dealer.
Pressing any of the four DIC buttons will
acknowledge the message and clear it from the
DIC display. If your vehicle does not have the four
DIC buttons, pressing the trip odometer reset
stem will acknowledge the message and clear it
from the DIC display.
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. See
Malfunction Indicator Lamp on page 258. Fully
reinstall the fuel cap. SeeFilling the Tank
on page 474. 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 363.
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Heavy-DutyTrailer Wiring Harness
Package
For vehicles equipped with heavy duty trailering,
the harness is connected to the trailer 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 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 voltage and
charge the battery.
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