2010 GMC SIERRA DENALI service

The voltmeter gage may also read lower when in fuel
economy mode. This is normal.
Readings in the low warning zone can 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.
The vehicle can only be driven for a short time with the
reading in either warning zone. If the vehicle must be
driven, 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.Brake System Warning Light
With the ignition on, the brake system warning light
comes on when the parking brake is set. If the vehicle
is driven with the parking brake engaged, a chime
sounds when the vehicle speed is greater than
8 km/h (5 mph).
The vehicle's hydraulic brake system is divided into two
parts. If one part is not working, the other part can still
work and stop the vehicle. For good braking, both parts
need to be working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have the brake system
inspected right away.
This light can also come on due to low brake fluid. See
Brakes
on page 6‑40for more information.
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United StatesCanada
This light comes on briefly when the ignition key is
turned to ON/RUN. If it does not come on then, have it
fixed so it is ready to warn if there is a problem.
{WARNING:
The brake system might not be working properly if
the brake system warning light is on. Driving with
the brake system warning light on can lead to a
crash. If the light is still on after the vehicle has
been pulled off the road and carefully stopped,
have the vehicle towed for service.
If the light comes on while driving, pull off the road and
stop carefully. The pedal might be harder to push or
might go closer to the floor. It can take longer to stop.
If the light is still on, have the vehicle towed for service.
See Towing Your Vehicle on page 5‑38.
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Antilock Brake System (ABS)
Warning Light
For vehicles with the
Antilock Brake System
(ABS), this light comes on
briefly when the engine is
started.
If it does not, have the vehicle serviced by your dealer/
retailer. If the system is working normally the indicator
light then goes off.
If the ABS light stays on, turn the ignition off. If the light
comes on while driving, stop as soon as it is safely
possible and turn the ignition off. Then start the engine
again to reset the system. If the ABS light stays on,
or comes on again while driving, the vehicle needs
service. If the regular brake system warning light is not
on, the vehicle still has brakes, but not antilock brakes.
If the regular brake system warning light is also on, the
vehicle does not have antilock brakes and there is a
problem with the regular brakes. See Brake System
Warning Light on page 4‑34.
For vehicles with a Driver Information Center (DIC), see
DIC Warnings and Messages
on page 4‑57for all
brake related DIC messages.
StabiliTrak®Indicator Light
For vehicles with the
StabiliTrak®system, this
light comes on briefly
while starting the engine.
If it does not, have the vehicle serviced by your dealer/
retailer. If the system is working normally the indicator
light then goes off.
If the light comes on and stays on while driving, there
could be a problem with the StabiliTrak
®system and the
vehicle might need service. When this warning light is
on, the StabiliTrak
®system is off and does not limit
wheel spin.
The light flashes if the system is active and is working
to assist the driver with directional control of the vehicle
in difficult driving conditions.
See StabiliTrak
®Systemon page 5‑6for more
information.
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When the Light Flashes First and Then is
On Steady
This indicates that there may be a problem with the Tire
Pressure Monitor System. The light flashes for about a
minute and stays on steady for the remainder of the
ignition cycle. This sequence repeats with every ignition
cycle. SeeTire Pressure Monitor Operation
on
page 6‑74for more information.
Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation of
the fuel, ignition, and emission control systems.
It ensures that emissions are at acceptable levels for
the life of the vehicle, helping to produce a cleaner
environment.
This light should come on
when the ignition is on,
but the engine is not
running, as a check to
show it is working. If it
does not, have the vehicle
serviced by your dealer/
retailer. If the check engine light comes on and stays on, while
the engine is running, this indicates that there is an
OBD II problem and service is required.
Malfunctions often are indicated by the system before
any problem is apparent. Being aware of the light can
prevent more serious damage to the vehicle. This
system assists the service technician in correctly
diagnosing any malfunction.
Notice:
If the vehicle is continually driven with this
light on, after a while, the emission controls might
not work as well, the vehicle's fuel economy might
not be as good, and the engine might not run as
smoothly. This could lead to costly repairs that
might not be covered by the vehicle warranty.
Notice: Modifications made to the engine,
transmission, exhaust, intake, or fuel system of the
vehicle or the replacement of the original tires with
other than those of the same Tire Performance
Criteria (TPC) can affect the vehicle's emission
controls and can cause this light to come on.
Modifications to these systems could lead to costly
repairs not covered by the vehicle warranty. This
could also result in a failure to pass a required
Emission Inspection/Maintenance test. See
Accessories and Modifications on page 6‑4.
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This light comes on during a malfunction in one of
two ways:
Light Flashing :A misfire condition has been detected.
A misfire increases vehicle emissions and could
damage the emission control system on the vehicle.
Diagnosis and service might be required.
To prevent more serious damage to the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If towing a trailer, reduce the amount of cargo
being hauled as soon as it is possible.
If the light continues to flash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the key off, wait at least 10 seconds, and restart
the engine. If the light is still flashing, follow the
previous steps and see your dealer/retailer for service
as soon as possible.
Light On Steady : An emission control system
malfunction has been detected on the vehicle.
Diagnosis and service might be required.
An emission system malfunction might be corrected by
doing the following:
.Make sure the fuel cap is fully installed. See Filling
the Tankon page 6‑10. The diagnostic system
can determine if the fuel cap has been left off or improperly installed. A loose or missing fuel cap
allows fuel to evaporate into the atmosphere. A few
driving trips with the cap properly installed should
turn the light off.
.If the vehicle has been driven through a deep
puddle of water, the vehicle's electrical system
might be wet. The condition is usually corrected
when the electrical system dries out. A few driving
trips should turn the light off.
.Make sure to fuel the vehicle with quality fuel. Poor
fuel quality causes the engine not to run as
efficiently as designed and can cause: stalling after
start-up, stalling when the vehicle is changed into
gear, misfiring, hesitation on acceleration,
or stumbling on acceleration. These conditions
might go away once the engine is warmed up.
If one or more of these conditions occurs, change
the fuel brand used. It will require at least one full
tank of the proper fuel to turn the light off.
See Gasoline Octane on page 6‑7.
If none of the above have made the light turn off, your
dealer/retailer can check the vehicle. The dealer/retailer
has the proper test equipment and diagnostic tools to fix
any mechanical or electrical problems that might have
developed.
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{WARNING:
Do not keep driving if the oil pressure is low. The
engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice: Lack of proper engine oil maintenance can
damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
Oil Pressure Light
{WARNING:
Do not keep driving if the oil pressure is low. The
engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice: Lack of proper engine oil maintenance can
damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
This light comes on briefly while starting the engine. If it
does not, have the vehicle serviced by your dealer/
retailer. If the system is working normally the indicator
light then goes off.
If the light comes on and stays on, it means that oil is
not flowing through the engine properly. The vehicle
could be low on oil and it might have some other
system problem.
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Remember, you must reset the OIL LIFE display
yourself after each oil change. It will not reset itself.
Also, be careful not to reset the OIL LIFE display
accidentally at any time other than when the oil has just
been changed. It cannot be reset accurately until the
next oil change. To reset the engine oil life system, see
Engine Oil Life System on page 6‑20.
Units
Press the vehicle information button until UNITS
displays. This display allows you to select between
English or Metric units of measurement. Once in this
display, press the set/reset button to select between
ENGLISH or METRIC units. All of the vehicle
information will then be displayed in the unit of
measurement selected.
Tire Pressure
If your vehicle has the Tire Pressure Monitor System
(TPMS), the pressure for each tire can be viewed in the
DIC. The tire pressure will be shown in either pounds
per square inch (psi) or kilopascals (kPa). Press the
vehicle information button until the DIC displays FRONT
TIRES PSI (kPa) LEFT ## RIGHT ##. Press the vehicle
information button again until the DIC displays REAR
TIRES PSI (kPa) LEFT ## RIGHT ##.If a low tire pressure condition is detected by the
system while driving, a message advising you to add
pressure in a specific tire will appear in the display. See
Inflation - Tire Pressure
on page 6‑71and
DIC
Warnings and Messageson page 4‑57for more
information.
If the tire pressure display shows dashes instead of a
value, there may be a problem with your vehicle. If this
consistently occurs, see your dealer/retailer for service.
Trailer Gain and Output
On vehicles with the Integrated Trailer Brake Control
(ITBC) system, the trailer brake display appears in the
DIC. Press the vehicle information button until TRAILER
GAIN and OUTPUT display.
TRAILER GAIN shows the trailer gain setting. This
setting can be adjusted from 0.0 to 10.0 with either a
trailer connected or disconnected. To adjust this setting,
see “Integrated Trailer Brake Control System” under
Towing a Trailer
on page 5‑42for more information.
OUTPUT shows the power output to the trailer anytime
a trailer with electric brakes is connected. Output is
displayed in 0 to 10 bars. Dashes may appear in the
OUTPUT display. See “Integrated Trailer Brake Control
System” underTowing a Trailer
on page 5‑42for more
information.
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BATTERY LOW START VEHICLE
When the vehicle’s battery is severely discharged, this
message will display and four chimes will sound. Start
the vehicle immediately. If the vehicle is not started and
the battery continues to discharge, the climate controls,
heated seats, and audio systems will shut off and the
vehicle may require a jump start. These systems will
function again after the vehicle is started.
CHANGE ENGINE OIL SOON
This message displays when the engine oil needs to be
changed. When you change the engine oil, be sure to
reset the CHANGE ENGINE OIL SOON message. See
Engine Oil Life System
on page 6‑20for information on
how to reset the message. See Engine Oilon
page 6‑18and Scheduled Maintenanceon page 7‑3for more information.
CHECK TRAILER WIRING
On vehicles with the Integrated Trailer Brake Control
(ITBC) system, this message may display and a chime
may sound when one of the following conditions exists:
.A trailer with electric brakes becomes
disconnected from the vehicle.
‐If the disconnect occurs while the vehicle is
stopped, this message clears itself after a
short time.
‐ If the disconnect occurs while the vehicle is
moving, this message stays on until the ignition
is turned off.
.There is a short in the wiring to the electric trailer
brakes.
When this message displays, power is no longer
available to the trailer brakes.
As soon as it is safe to do so, carefully pull your vehicle
over to the side of the road and turn the ignition off.
Check the wiring connection to the trailer and turn the
ignition back on. This message clears if the trailer is
reconnected. This message also clears if you
acknowledge it. If this message still displays, either
your vehicle or the trailer needs service. See your
dealer/retailer.
See “Integrated Trailer Brake Control System” under
Towing a Trailer
on page 5‑42for more information.
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