check engine HUMMER H2 2008 User Guide

This light comes on, as a check to show it is working,
when the ignition is turned ON/RUN but the engine is not
running. If the light does not come on, have it repaired.
This light also comes on during a malfunction in
one of two ways:
Light Flashing— A misre condition has been
detected. A misre increases vehicle emissions
and could damage the emission control system
on your vehicle. Diagnosis and service might
be required.
Light On Steady— An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service might be required.
If the Light is Flashing
The following can prevent more serious damage
to your vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If you are towing a trailer, reduce the amount
of cargo being hauled as soon as it is possible.If the light stops ashing and remains on steady,
see “If the Light Is On Steady” following.
If the light continues to ash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the ignition off, wait at least 10 seconds, and restart
the engine. If the light remains on steady, see “If the
Light Is On Steady” following. If the light is still ashing,
follow the previous steps and see your dealer/retailer
for service as soon as possible.
If the Light Is On Steady
You might be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install the
cap. SeeFilling the Tank on page 5-7. 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.
Did you just drive through a deep puddle of water?
If so, your 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.
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Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel.
SeeGasoline Octane on page 5-5. Poor fuel quality
causes the engine not to run as efficiently as designed.
You might notice this as stalling after start-up, stalling
when you put the vehicle into gear, misring, hesitation
on acceleration, or stumbling on acceleration — these
conditions might go away once the engine is warmed up.
This will be detected by the system and cause the
light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn
off, your dealer/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have
or might begin programs to inspect the emission
control equipment on your vehicle. Failure to pass
this inspection could prevent you from getting a
vehicle registration.
Here are some things you need to know to help
your vehicle pass an inspection:
Your vehicle will not pass this inspection if the check
engine light is on or not working properly.
Your vehicle will not pass this inspection if the
OBD (on-board diagnostic) system determines that
critical emission control systems have not been
completely diagnosed by the system. The vehicle
would be considered not ready for inspection. This can
happen if you have recently replaced the battery or
if the battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This can take several days
of routine driving. If you have done this and your
vehicle still does not pass the inspection for lack of
OBD system readiness, your dealer/retailer can prepare
the vehicle for inspection.
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Oil Pressure Gage
The oil pressure gage shows the engine oil pressure
in psi (pounds per square inch) when the engine
is running. Canadian vehicles indicate pressure
in kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.When the oil pressure reaches the low pressure zone,
the OIL PRESSURE LOW STOP ENGINE message
will appear in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 3-56and
Engine Oil on page 5-13for more information.
A reading in the low pressure zone may be caused by a
dangerously low oil level or some other problem causing
low oil pressure. Check your oil as soon as possible.
{CAUTION:
Do not keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil. United StatesCanada
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Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low.
If you do, your engine can become so hot that
it catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be covered
by your warranty. Always follow the maintenance
schedule in this manual for changing engine oil.
This light will come on
briey when you start your
engine. If it does not,
have your vehicle serviced.
When the light comes on and stays on, it means that
oil is not owing through your engine properly. You could
be low on oil and you might have some other system
problem.
Security Light
For information regarding
this light and the vehicle’s
security system, see
Content Theft-Deterrent
on page 2-24.
Cruise Control Light
This light comes on
whenever you set
the cruise control.
The light goes out when the cruise control is turned off.
SeeCruise Control on page 3-12for more information.
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When the remaining oil life is low, the CHANGE
ENGINE OIL SOON message will appear on the display.
See “CHANGE ENGINE OIL SOON” underDIC
Warnings and Messages on page 3-56. You should
change the oil as soon as you can. SeeEngine Oil
on page 5-13. In addition to the engine oil life system
monitoring the oil life, additional maintenance is
recommended in the Maintenance Schedule in this
manual. SeeScheduled Maintenance on page 6-4
for more information.
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,
seeEngine Oil Life System on page 5-16.
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
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 or high tire pressure condition is detected by
the system while driving, a message advising you
to check the pressure in a specic tire will appear in
the display. SeeInflation - Tire Pressure on page 5-61
andDIC Warnings and Messages on page 3-56for
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.
Engine Hours
Press the vehicle information button until
ENGINE HOURS displays. This display shows
the total number of hours the engine has run.
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DIC Warnings and Messages
Messages are displayed on the 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. Multiple messages may appear
one after another.
Some messages may not require immediate action,
but you can press any of the DIC buttons on the
instrument panel or the trip odometer reset stem on
the instrument panel cluster to acknowledge that
you received the messages and to clear them from
the display.
Some messages cannot be cleared from the DIC
display because they are more urgent. These messages
require action before they can be cleared. 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.
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.
SeeEngine Oil Life System on page 5-16for information
on how to reset the message. SeeEngine Oil on
page 5-13andScheduled Maintenance on page 6-4
for more information.
CHECK TIRE PRESSURE
This message displays when the pressure in one
or more of the vehicle’s tires needs to be checked. This
message also displays LEFT FRONT, RIGHT FRONT,
LEFT REAR, or RIGHT REAR to indicate which tire
needs to be checked. You can receive more than one
tire pressure message at a time. To read the other
messages that may have been sent at the same time,
press the set/reset button or the trip odometer reset
stem. If a tire pressure message appears on the DIC,
stop as soon as you can. Have the tire pressures
checked and set to those shown on the Tire Loading
Information label. SeeTires on page 5-55,Loading Your
Vehicle on page 4-44, andInflation - Tire Pressure on
page 5-61. The DIC also shows the tire pressure values.
See “DIC Operation and Displays (Using DIC Buttons)”
earlier in this section. If the tire pressure is low,
the low tire pressure warning light comes on.
SeeTire Pressure Light on page 3-41.
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DRIVER DOOR OPEN
This message displays and a chime sounds if the
driver door is not fully closed and the vehicle is in a
drive gear. Stop and turn off the vehicle, check the
door for obstructions, and close the door again.
Check to see if the message still appears on the DIC.
ENGINE HOT A/C (Air Conditioning)
TURNED OFF
This message displays when the engine coolant
becomes hotter than the normal operating temperature.
SeeEngine Coolant Temperature Gage on page 3-40.
To avoid added strain on a hot engine, the air
conditioning compressor automatically turns off.
When the coolant temperature returns to normal,
the air conditioning compressor turns back on.
You can continue to drive your vehicle.
If this message continues to appear, have the
system repaired by your dealer/retailer as soon
as possible to avoid damage to the engine.
ENGINE OVERHEATED IDLE ENGINE
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon
as possible. SeeEngine Overheating on page 5-27
for more information.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle to
idle until it cools down. SeeEngine Coolant
Temperature Gage on page 3-40.
SeeOverheated Engine Protection Operating Mode
on page 5-28for information on driving to a safe place
in an emergency.
ENGINE POWER IS REDUCED
This message displays and a chime sounds when
the cooling system temperature gets too hot and the
engine further enters the engine coolant protection
mode. SeeEngine Overheating on page 5-27for
further information.
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This message also displays when the vehicle’s engine
power is reduced. Reduced engine power can affect the
vehicle’s ability to accelerate. If this message is on,
but there is no reduction in performance, proceed
to your destination. The performance may be reduced
the next time the vehicle is driven. The vehicle may
be driven at a reduced speed while this message is on,
but acceleration and speed may be reduced. Anytime
this message stays on, the vehicle should be taken
to your dealer/retailer for service as soon as possible.
FUEL LEVEL LOW
This message displays and a chime sounds if the
fuel level is low. Refuel as soon as possible.
SeeFuel Gage on page 3-47andFuel on page 5-5
for more information.
HOOD OPEN
This message displays and a chime sounds if the
hood is not fully closed. Stop and turn off the vehicle,
check the hood for obstructions, and close the hood
again. Check to see if the message still appears
on the DIC.
LEFT REAR DOOR OPEN
This message displays and a chime sounds if the driver
side rear door is not fully closed and the vehicle is in
a drive gear. Stop and turn off the vehicle, check
the door for obstructions, and close the door again.
Check to see if the message still appears on the DIC.
OIL PRESSURE LOW STOP ENGINE
Notice:If you drive your vehicle while the engine
oil pressure is low, severe engine damage may
occur. If a low oil pressure warning appears on the
Driver Information Center (DIC), stop the vehicle
as soon as possible. Do not drive the vehicle until
the cause of the low oil pressure is corrected.
SeeEngine Oil on page 5-13for more information.
This message displays if low oil pressure levels
occur. Stop the vehicle as soon as safely possible and
do not operate it until the cause of the low oil pressure
has been corrected. Check the oil as soon as possible
and have your vehicle serviced by your dealer/retailer.
SeeEngine Oil on page 5-13.
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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 3-34andAirbag System on page 1-64for
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 3-37. 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 3-38. 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 STABILITRAK
This message displays when 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.
SERVICE SUSPENSION SYSTEM
This message displays if a problem occurs with the
suspension 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, there is a problem with
the air suspension system. See your dealer/retailer
for service.
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TIGHTEN GAS CAP
This message may display along with the check engine
light on the instrument panel cluster if the vehicle’s
fuel cap is not tightened properly. SeeMalfunction
Indicator Lamp on page 3-42. Reinstall the fuel cap
fully. SeeFilling the Tank on page 5-7. 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 this light and message off.
TIRE LEARNING ACTIVE
This message displays when the Tire Pressure Monitor
System (TPMS) is re-learning the tire positions on your
vehicle. The tire positions must be re-learned after
rotating the tires or after replacing a tire or sensor. See
Tire Inspection and Rotation on page 5-67,Tire Pressure
Monitor System on page 5-62, andInflation - Tire
Pressure on page 5-61for more information.
TRACTION CONTROL OFF
This message displays when you turn off the Traction
Control System (TCS) or when the TCS has been
automatically disabled. Adjust your driving accordingly.
SeeTraction Control System (TCS) on page 4-5and
StabiliTrak
®System on page 4-7for more information.
TCS may be automatically disabled due to overheating,
which could occur if the TCS activates continuously
for an extended period of time.
TRANSMISSION HOT IDLE ENGINE
Notice:If you drive your vehicle while the
transmission uid is overheating and the
transmission temperature warning is displayed
on the instrument panel cluster and/or DIC, you
can damage the transmission. This could lead
to costly repairs that would not be covered by
your warranty. Do not drive your vehicle with
overheated transmission uid or while the
transmission temperature warning is displayed.
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