2005 HUMMER H2 coolant level

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
charging system light on the instrument panel cluster
will come on. SeeCharging System Light on page 3-31
for more information. Driving with this problem could
drain your 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
GM dealer immediately.
CHECK OIL LEVEL
If 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 or the trip odometer reset
stem will clear this message from the DIC display. This
message will clear itself after 10 seconds until the
next ignition cycle.
CHECK WASHER FLUID
If the washer uid level is low, this message will appear
on the DIC. Adding washer uid will clear the message.
Pressing any of the four DIC buttons or the trip
odometer reset stem will clear it from the DIC display.
This message will clear itself after 10 seconds until
the next ignition cycle.
DRIVER DOOR AJAR
If the driver’s door is not fully closed and the vehicle is in
a drive gear, this message will appear on the display and
you will hear a chime. Stop and turn off the vehicle, check
the door for obstacles, and close the door again. Check to
see if the message still appears on the DIC. Pressing any
of the four DIC buttons or the trip odometer reset stem
will clear the message from the DIC display.
ENGINE COOLANT HOT
If the cooling system temperature gets hot, this message
will appear in the DIC. Stop the vehicle and let the
engine idle in PARK (P) to allow the coolant to reach a
safe temperature. This message will clear when the
coolant temperature drops to a safe operating
temperature. Pressing any of the four DIC buttons or
the trip odometer reset stem will clear the message from
the DIC display.
3-48

ENGINE OVERHEATED
If the engine cooling system reaches unsafe
temperatures for operation, this message will appear in
the DIC and you will hear a chime. Stop and turn off
the vehicle as soon as it is safe to do so to avoid severe
damage. This message will clear when the engine
has cooled to a safe operating temperature.
FUEL LEVEL LOW
If the fuel level is low, this message will appear on the
DIC and you will hear a chime. Refuel as soon as
possible. Pressing any of the four DIC buttons or the
trip odometer reset stem will clear the message from the
DIC display. It will also clear itself after 10 seconds.
The low fuel light near the fuel gage will still remain on
in either case.
KEYFOB X BATTERY LOW
If a remote keyless entry transmitter battery is low, this
message will appear on the DIC. The battery needs
to be replaced in the transmitter. See “Battery
Replacement” underRemote Keyless Entry System
Operation on page 2-5. Pressing any of the four
DIC buttons or the trip odometer reset stem will clear
the message from the DIC display.
LEFT REAR DOOR AJAR
If the driver’s side rear door is not fully closed and the
vehicle is in a drive gear, this message will appear
on the display and you will hear a chime. Stop and turn
off the vehicle, check the door for obstacles, and
close the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC
buttons or the trip odometer reset stem will clear the
message from the DIC display.
LOW COOLANT LEVEL
If your vehicle has a low coolant sensor and the engine
coolant level is low, this message will appear on the
DIC. Adding coolant will clear the message. This
message will clear itself after 10 seconds until the next
ignition cycle.
OIL LIFE RESET
This message will appear on the display for about
10 seconds after resetting the change engine oil
message.
3-49

OIL PRESSURE LOW
If low oil pressure levels occur, this message will be
displayed on the DIC and a chime will sound. 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 your oil as soon as possible and have
your vehicle serviced by your GM dealer.
PASSENGER DOOR AJAR
If the passenger’s door is not fully closed and the
vehicle is in a drive gear, this message will appear on
the display and you will hear a chime. Stop and turn off
the vehicle, check the door for obstacles, and close
the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC
buttons or the trip odometer reset stem will clear the
message from the DIC display.
REAR ACCESS OPEN
On the SUV, if the liftgate is open while the ignition is in
RUN, this message will appear on the DIC and you will
hear a chime. Turn off the vehicle and check the liftgate.
Restart the vehicle and check for the message on the DIC
display. Pressing any of the four DIC buttons or the trip
odometer reset stem will clear the message from the DIC
display.On the SUT, if the midgate is open or one or both of the
midgate latches are not fully closed, this message will
appear on the DIC. Turn off the vehicle and check that
the midgate and the latches are closed. Restart the
vehicle and check for the message on the DIC display.
Pressing any of the four DIC buttons or the trip odometer
reset stem will clear the message from the DIC display.
REDUCED ENGINE POWER
This message is displayed when the cooling system
temperature gets too hot and the engine further enters
the engine coolant protection mode.
SeeEngine Overheating on page 5-26for further
information.
You may also see this message when the vehicle
determines a problem with the electronic throttle control.
See your GM dealer for service.
REPLACE LIFTGATE FUSE
This message will be displayed if the liftgate lock
malfunctions and/or the liftgate fuse blows. For more
information on fuses, seeInstrument Panel Fuse Block
on page 5-103andUnderhood Fuse Block on
page 5-107.
If the message returns after replacing the fuse, see your
GM dealer for service.
3-50

Turn Signals When Towing a Trailer
The arrows on your instrument panel will ash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will also ash, telling other drivers
you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
You can tow in DRIVE (D). You may want to shift the
transmission to THIRD (3) or, if necessary, a lower
gear selection if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).You may also want to activate the tow/haul mode if
the transmission shifts too often. See “Tow/Haul
Mode” earlier.
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 you turn your
engine off immediately after towing at high altitude
on steep uphill grades, your 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 PARK (P) for a
few minutes before turning the engine off. If you do get
the overheat warning, seeEngine Overheating on
page 5-26.
4-76

A. Coolant Surge Tank. SeeCooling System on
page 5-29andCoolant Surge Tank Pressure Cap
on page 5-26.
B. Engine Air Cleaner/Filter and Air Filter Restriction
Indicator (If Equipped). SeeEngine Air Cleaner/Filter
on page 5-18.
C. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-34.
D. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-13.
E. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-13.
F. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-21.
G. Fan. SeeCooling System on page 5-29.
H. Remote Negative (−) Terminal (GND). SeeJump
Starting on page 5-39.
I. Power Steering Fluid Reservoir (Out of View). See
Power Steering Fluid on page 5-33.
J. Remote Positive (+) Terminal. SeeJump Starting on
page 5-39.
K. Brake Fluid Reservoir. See “Brake Fluid” under
Brakes on page 5-35.
L. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-107.
M. Battery. SeeBattery on page 5-38.Engine Oil
If the CHECK OIL LEVEL message appears on the
Driver Information Center (DIC), it means you need to
check your engine oil level right away. For more
information, see CHECK OIL LEVEL underDIC
Warnings and Messages on page 3-47.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It is a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop. See
Engine Compartment Overview on page 5-12for
the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
5-13

If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
Checking Coolant
The coolant surge tank is
located in the engine
compartment on the
passenger’s side of the
vehicle. SeeEngine
Compartment Overview on
page 5-12for more
information on location.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap — even a little — when the engine and
radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD mark.
If your vehicle is equipped with the LOW COOLANT
LEVEL message and it comes on and stays on, it means
you are low on engine coolant.
See “Low Coolant Level” underDIC Warnings and
Messages on page 3-47.
5-25

Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan
If the coolant inside the coolant surge tank is boiling, do
not do anything else until it cools down. The vehicle
should be parked on a level surface.The coolant level should be at or above the FULL
COLD mark. If it is not, you may have a leak at the
pressure cap or in the radiator hoses, heater hoses,
radiator, water pump or somewhere else in the
cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them. If
you do, you can be burned.
Do not run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine re, and you could be
burned. Get any leak xed before you drive
the vehicle.
If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal
down. If it does not, your vehicle needs service. Turn off
the engine.
5-29

Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-28for information on driving to a safe place
in an emergency.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the coolant level is not at or above the FULL COLD
mark, add a 50/50 mixture ofclean, drinkable water
and DEX-COOL
®coolant at the coolant surge tank, but
be sure the cooling system, including the coolant
surge tank pressure cap, is cool before you do it. See
Engine Coolant on page 5-24for more information.If no coolant is visible in the surge tank, add coolant
as follows:
{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the radiator
pressure cap — even a little — they can come
out at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap, is hot. Wait for the cooling system and
radiator pressure cap to cool if you ever have
to turn the pressure cap.
5-30