engine overheat HUMMER H2 2009 Owners Manual

Starting Procedure
1. With your foot off the accelerator pedal, turn the
ignition to START. When the engine starts, let go of
the key. The idle speed will slow down as the engine
warms. Do not race the engine immediately after
starting it. Operate the engine and transmission
gently to allow the oil to warm up and lubricate all
moving parts.
The vehicle has a Computer-Controlled Cranking
System. This feature assists in starting the engine
and protects components. If the ignition key is turned
to the START position, and then released when the
engine begins cranking, the engine will continue
cranking for a few seconds or until the vehicle starts.
If the engine does not start and the key is held in
START, cranking will be stopped after 15 seconds
to prevent cranking motor damage. To prevent gear
damage, this system also prevents cranking if the
engine is already running. Engine cranking can
be stopped by turning the ignition switch to the
ACC/ACCESSORY or LOCK/OFF position.
Notice:Cranking the engine for long periods of
time, by returning the key to the START position
immediately after cranking has ended, can overheat
and damage the cranking motor, and drain the
battery. Wait at least 15 seconds between each try,
to let the cranking motor cool down.2. If the engine does not start after 5-10 seconds,
especially in very cold weather (below 0°F or−18°C),
it could be ooded with too much gasoline.
Try pushing the accelerator pedal all the way to
the oor and holding it there as you hold the key in
START for up to a maximum of 15 seconds. Wait at
least 15 seconds between each try, to allow the
cranking motor to cool down. When the engine starts,
let go of the key and accelerator. If the vehicle starts
briey but then stops again, repeat these steps.
This clears the extra gasoline from the engine.
Do not race the engine immediately after starting it.
Operate the engine and transmission gently until
the oil warms up and lubricates all moving parts.
Notice:The engine is designed to work with the
electronics in the vehicle. If you add electrical parts
or accessories, you could change the way the
engine operates. Before adding electrical equipment,
check with your dealer/retailer. If you do not, the
engine might not perform properly. Any resulting
damage would not be covered by the vehicle
warranty.
2-30

Engine Coolant Heater
The engine heater can provide easier starting and better
fuel economy during engine warm-up in cold weather
conditions at or below 0°F (−18°C). Vehicles with an
engine heater should be plugged in at least four hours
before starting. An internal thermostat in the plug-end of
the cord may exist which will prevent engine coolant
heater operation at temperatures above 0°F (−18°C).
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Locate the electrical cord near the front recovery
loop on the driver side of the vehicle.
3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet could
cause an electrical shock. Also, the wrong kind of
extension cord could overheat and cause a re.
You could be seriously injured. Plug the cord into a
properly grounded three-prong 110-volt AC outlet.
If the cord will not reach, use a heavy-duty
three-prong extension cord rated for at least
15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts.
The length of time the heater should remain plugged
in depends on several factors. Ask a dealer/retailer
in the area where you will be parking the vehicle for
the best advice on this.
2-31

Shifting Into Park
{CAUTION:
It can be dangerous to get out of the vehicle if the
shift lever is not fully in P (Park) with the parking
brake rmly set. The vehicle can roll. If you have
left the engine running, the vehicle can move
suddenly. You or others could be injured. To be
sure the vehicle will not move, even when you are
on fairly level ground, use the steps that follow.
If you are pulling a trailer, seeTowing a Trailer
on page 4-55.
1. Hold the brake pedal down and set the parking
brake. SeeParking Brake on page 2-42for more
information.
2. Move the shift lever into P (Park) by pressing the
button on the shift lever and pushing the lever all
the way toward the front of the vehicle.
3. Turn the ignition key to LOCK/OFF.
4. Remove the key and take it with you. If you can
leave the vehicle with the key, the vehicle is in
P (Park).
Leaving the Vehicle With the Engine
Running
{CAUTION:
It can be dangerous to leave the vehicle with the
engine running. The vehicle could move suddenly if
the shift lever is not fully in P (Park) with the parking
brake rmly set. And, if you leave the vehicle with
the engine running, it could overheat and even
catch re. You or others could be injured. Do not
leave the vehicle with the engine running.
If you have to leave the vehicle with the engine running,
be sure the vehicle is in P (Park) and the parking
brake is rmly set before you leave it. After you have
moved the shift lever into P (Park), hold the regular
brake pedal down. Then, see if you can move the shift
lever away from P (Park) without rst pressing the
button on the console shift lever. If you can, it means
that the shift lever was not fully locked into P (Park).
2-43

Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard the vehicle is
working. During a majority of the operation, the gage
reads 210°F (100°C) or less. If the vehicle is pulling a
load or going up hills, it is normal for the temperature to
uctuate and approach the 250°F (122°C) mark. If the
gage reaches the 260°F (125°C) mark, it indicates that
the cooling system is working beyond its capacity.
SeeEngine Overheating on page 5-33.
Tire Pressure Light
For vehicles with a tire
pressure light, this light
comes on briey when
the engine is started.
It provides information about tire pressures and the
Tire Pressure Monitoring System.
When the Light is On Steady
This indicates that one or more of the tires is signicantly
underinated.
A tire pressure message in the Driver Information
Center (DIC), can accompany the light. SeeDIC
Warnings and Messages on page 3-56for more
information. Stop and check the tires as soon as it is
safe to do so. If a tire is underinated, inate to the
proper pressure. SeeTires on page 5-57for more
information. United States
Canada
3-39

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

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 5-33for further
information.
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 3-45andFuel on page 5-5for more information.
HEATED WASHER FLUID SYSTEM OFF
This message displays when the heated windshield
washer has been turned off. SeeWindshield Washer
on page 3-10for more information.
HEATING WASH FLUID WASH WIPES
PENDING
This message displays when the heated windshield
washer system is heating the uid. SeeWindshield
Washer on page 3-10for 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.
ICE POSSIBLE DRIVE WITH CARE
This message displays when ice conditions are possible.
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 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.
3-58

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 4-9
andStabiliTrak
®System on page 4-6for 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.This message displays along with a continuous chime
if the transmission uid in the vehicle gets hot. Driving
with the transmission uid temperature high can cause
damage to the vehicle. Stop the vehicle and let it idle to
allow the transmission to cool. This message clears and
the chime stops when the uid temperature reaches a
safe level.
TURN SIGNAL ON
This message displays and a chime sounds if a turn
signal is left on for 3/4 of a mile (1.2 km). Move the turn
signal/multifunction lever to the off position.
WASHER FLUID LOW ADD FLUID
This message displays when the windshield washer uid
is low. Fill the windshield washer uid reservoir as soon
as possible. SeeEngine Compartment Overview on
page 5-14for the location of the windshield washer
uid reservoir. Also, seeWindshield Washer Fluid
on page 5-37for more information.
3-63

Driving Downhill
When off-roading takes you downhill, consider:
How steep is the downhill? Will I be able to maintain
vehicle control?
What is the surface like? Smooth? Rough?
Slippery? Hard-packed dirt? Gravel?
Are there hidden surface obstacles? Ruts? Logs?
Boulders?
What is at the bottom of the hill? Is there a hidden
creek bank or even a river bottom with large rocks?
If you decide you can go down a hill safely, try to keep
the vehicle headed straight down. Use a low gear
so engine drag can help the brakes so they do not have
to do all the work. Descend slowly, keeping the
vehicle under control at all times.
{CAUTION:
Heavy braking when going down a hill can cause
your brakes to overheat and fade. This could cause
loss of control and a serious accident. Apply the
brakes lightly when descending a hill and use a low
gear to keep vehicle speed under control.Things not to do when driving down a hill:
When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too
steep to drive down might be too steep to drive
across. The vehicle could roll over.
Never go downhill with the transmission in
N (Neutral), called free-wheeling. The brakes will
have to do all the work and could overheat
and fade.
Vehicles are much more likely to stall when going uphill,
but if it happens when going downhill:
1. Stop the vehicle by applying the regular brakes and
apply the parking brake.
2. Shift to P (Park). While still braking, restart the
engine.
3. Shift back to a low gear, release the parking brake,
and drive straight down.
4. If the engine will not start, get out and get help.
4-29

Repeat this until help arrives but only when you feel
really uncomfortable from the cold. Moving about
to keep warm also helps.
If it takes some time for help to arrive, now and then
when you run the engine, push the accelerator
pedal slightly so the engine runs faster than the idle
speed. This keeps the battery charged to restart
the vehicle and to signal for help with the headlamps.
Do this as little as possible to save fuel.
If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
Slowly and cautiously spin the wheels to free the
vehicle when stuck in sand, mud, ice, or snow. See
Rocking Your Vehicle to Get It Out on page 4-40.
If the vehicle has a traction system, it can often help
to free a stuck vehicle. Refer to the vehicle’s traction
system in the Index. If stuck too severely for the traction
system to free the vehicle, turn the traction system off
and use the rocking method.
{CAUTION:
If you let your vehicle’s tires spin at high speed,
they can explode, and you or others could be
injured. The vehicle can overheat, causing an
engine compartment re or other damage. Spin
the wheels as little as possible and avoid going
above 35 mph (55 km/h) as shown on the
speedometer.
For information about using tire chains on the vehicle,
seeTire Chains on page 5-77.
4-39

The system includes a compressor, two height sensors
and two air springs supporting the vehicle.
The system is activated when the engine is started
and deactivated when the ignition is returned to OFF.
The engine must be running for the rear of the vehicle to
be raised and the doors must be closed to enable a
transition between Normal Ride Height and Extended
Ride Height.
The compressor may be heard while the system is
active and the release of air similar to a hissing sound
may also be heard. This is normal.
Load leveling will not function normally with the inater
hose attached to the inator outlet. Remove the
hose from the outlet when it is not in use. See
Accessory Inflator on page 5-78.Overload and Overheat Protection
Overload protection is designed to protect the air
suspension system and is an indication to the driver that
the vehicle is overloaded.
If the rear suspension remains at a low height, the rear
axle load has exceeded GAWR (Gross Axle Weight
Rating). When the overload protection mode is activated,
the compressor operates for about 30 seconds to one
minute without raising the vehicle depending on the
amount of overload. This will continue each time the
ignition is turned on until the rear axle load is reduced
below GAWR. The system may reactivate without cycling
the ignition if some of the excess load is removed.
If the total rear GAWR (Gross Axle Weight Rating) is
reached, the suspension may be slightly less than level.
This is normal and does not mean there is a problem
with the air suspension.
In some instances the compressor may stop working
due to being overheated. This is normal. In the instance
of an abnormal overheat condition though the
compressor will stop working and the SERVICE
SUSPENSION SYSTEM will be displayed on the DIC.
SeeDIC Warnings and Messages on page 3-56for
more information.
4-54