2009 HUMMER H2 check engine light

Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
might begin programs to inspect the emission control
equipment on the vehicle. Failure to pass this inspection
could prevent getting a vehicle registration.
Here are some things to know to help the vehicle pass
an inspection:
The vehicle will not pass this inspection if the check
engine light is on with the engine running, or if the
key is in ON/RUN and the light is not on.
The vehicle will not pass this inspection if the
OBD II (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 the battery has recently been replaced
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 this has been done and the
vehicle still does not pass the inspection for lack of
OBD II system readiness, your dealer/retailer can
prepare the vehicle for inspection.
Oil Pressure Gage
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.United States
Canada
3-42

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.
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 can 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 appears in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 3-56and
Engine Oil on page 5-15for more information.
A reading in the low pressure zone can be caused
by a dangerously low oil level or some other problem
causing low oil pressure. Check the oil as soon as
possible.Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
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 briey 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.
3-43

CHECK TIRE PRESSURE
On vehicles with the Tire Pressure Monitor
System (TPMS), 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 5-57,Loading the
Vehicle on page 4-44, andInflation - Tire Pressure on
page 5-63. 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 3-39.
DRIVER DOOR OPEN
This message displays and a chime sounds if the driver
door is not fully closed and the vehicle is shifted out
of P (Park). 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 3-39.
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 5-33
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 3-39.
SeeOverheated Engine Protection Operating Mode on
page 5-35for information on driving to a safe place
in an emergency.
3-57

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
On some models, 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.
SERVICE THEFT DETERRENT SYSTEM
This message displays when there is a problem with
the theft-deterrent system. The vehicle may or may not
restart so you may want to take the vehicle to your
dealer/retailer before turning off the engine. See
PASS-Key
®III+ Electronic Immobilizer Operation
on page 2-26for more information.
SERVICE TIRE MONITOR SYSTEM
On vehicles with the Tire Pressure Monitor
System (TPMS), this message displays if a part
on the TPMS is not working properly. The tire pressure
light also ashes and then remains on during the same
ignition cycle. SeeTire Pressure Light on page 3-39.
Several conditions may cause this message to appear.
SeeTire Pressure Monitor Operation on page 5-66for
more information. If the warning comes on and stays
on, there may be a problem with the TPMS. See your
dealer/retailer.
SERVICE TRACTION CONTROL
This message displays when there is a problem with
the Traction Control System (TCS). When this message
displays, the system will not limit wheel spin. Adjust
your driving accordingly. See your dealer/retailer
for service. SeeTraction Control System (TCS) on
page 4-9andStabiliTrak
®System on page 4-6for
more information.
3-61

STABILITRAK OFF
This message displays when you turn off StabiliTrak,
or when the stability control has been automatically
disabled. To limit wheel spin and realize the full benets
of the stability enhancement system, you should normally
leave StabiliTrak on. However, you should turn
StabiliTrak off if your vehicle gets stuck in sand, mud, ice,
or snow and you want to rock your vehicle to attempt to
free it, or if you are driving in extreme off-road conditions
and require more wheel spin. SeeIf Your Vehicle is Stuck
in Sand, Mud, Ice, or Snow on page 4-39. To turn the
StabiliTrak system on or off, seeStabiliTrak
®System
on page 4-6.
There are several conditions that can cause this
message to appear.
The message displays if an engine or vehicle
related problem has been detected and the vehicle
needs service. See your dealer/retailer.
The message also displays if the vehicle is shifted
into 4LO.
The message turns off as soon as the conditions that
caused the message to be displayed are no longer
present.
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 3-40. Reinstall the fuel cap
fully. SeeFilling the Tank on page 5-8. 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
On vehicles with the Tire Pressure Monitor
System (TPMS), this message displays when
the 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.
SeeTire Inspection and Rotation on page 5-69,
Tire Pressure Monitor System on page 5-64, and
Inflation - Tire Pressure on page 5-63for more
information.
3-62

Antilock Brake System (ABS)
This vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that helps prevent a
braking skid.
When the engine is started and the vehicle begins to
drive away, ABS checks itself. A momentary motor
or clicking noise might be heard while this test is going
on. This is normal.
If there is a problem with
the ABS, this warning light
stays on. SeeAntilock
Brake System (ABS)
Warning Light on
page 3-38.Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
A computer senses that the wheels are slowing down.
If one of the wheels is about to stop rolling, the computer
will separately work the brakes at each front wheel
and at both rear wheels.
ABS can change the brake pressure to each wheel, as
required, faster than any driver could. This can help
the driver steer around the obstacle while braking hard.
As the brakes are applied, the computer keeps
receiving updates on wheel speed and controls braking
pressure accordingly.
Remember: ABS does not change the time needed to get
a foot up to the brake pedal or always decrease stopping
distance. If you get too close to the vehicle in front of you,
there will not be enough time to apply the brakes if that
vehicle suddenly slows or stops. Always leave enough
room up ahead to stop, even with ABS.
4-5

Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. The vehicle could be damaged. Avoid
making very sharp turns while trailering.
When turning with a trailer, make wider turns than
normal. Do this so the trailer will not strike soft shoulders,
curbs, road signs, trees or other objects. Avoid jerky or
sudden maneuvers. Signal well in advance.
Turn Signals When Towing a Trailer
The arrows on the instrument panel ash whenever
signaling a turn or lane change. Properly hooked up, the
trailer lamps also ash, telling other drivers the vehicle
is turning, changing lanes or stopping.
When towing a trailer, the arrows on the instrument panel
ash for turns even if the bulbs on the trailer are burned
out. For this reason you may think other drivers are
seeing the signal when they are not. It is important to
check occasionally to be sure the trailer bulbs are still
working.
Driving On Grades
Reduce speed and shift to a lower gearbeforestarting
down a long or steep downgrade. If the transmission is
not shifted down, the brakes might have to be used so
much that they would get hot and no longer work well.
Vehicles can tow in D (Drive). Shift the transmission to
a lower gear if the transmission shifts too often under
heavy loads and/or hilly conditions.
The tow/haul mode may be used if the transmission
shifts too often. SeeTow/Haul Mode Light on page 3-44.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If the engine is
turned off immediately after towing at high altitude on
steep uphill grades, the vehicle may show signs similar to
engine overheating. To avoid this, let the engine run while
parked, preferably on level ground, with the automatic
transmission in P (Park) for a few minutes before turning
the engine off. If the overheat warning comes on, see
Engine Overheating on page 5-33.
4-65

Maintenance When Trailer Towing
The vehicle needs service more often when pulling a
trailer. See this manual’s Maintenance Schedule or Index
for more information. Things that are especially important
in trailer operation are automatic transmission uid,
engine oil, axle lubricant, belts, cooling system and brake
system. It is a good idea to inspect these before and
during the trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
Heavy-Duty Trailer Wiring Harness
Package
The vehicle is equipped with the seven-wire trailer towing
harness. This harness with a seven-pin universal trailer
connector is attached 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/Black: Battery Feed*
Dark Blue: Trailer Brake*
*There is a location in the Underhood Fuse Block for
these circuits, but they are not connected. They should
be connected, and proper fuses installed, by your
dealer/retailer or a qualied service center.
If 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.
4-67