2004 HUMMER H2 heater

If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.
2. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving – DRIVE (D).
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning doesn’t come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign of steam, push down the
accelerator until the engine speed is about twice as fast
as normal idle speed for at least three minutes while
you’re parked. If you still have the warning,turn off the
engine and get everyone out of the vehicleuntil it
cools down. Also, see “Overheated Engine Protection
Operating Mode” listed previously in this section.
You may decide not to lift the hood but to get service
help right away.Cooling System
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Fan
If the coolant inside the coolant surge tank is boiling,
don’t do anything else until it cools down. The vehicle
should be parked on a level surface.
5-30

The coolant level should
be at or above the FULL
COLD mark. If it isn’t,
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 doesn’t, your vehicle needs service. Turn off
the engine.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
“Overheated Engine Protection Operating Mode”
in the Index for 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.
5-31

{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will.
Yourvehicle’s coolant warning system is set
for the proper coolant mixture. With plain
water or the wrong mixture, your engine could
get too hot but you would not get the overheat
warning. Your engine could catch re and you
or others could be burned. Use a 50/50 mixture
of clean, drinkable water and DEX-COOL
®
coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.
1. Park the vehicle on a level surface.
2. Locate the coolant
surge tank pressure
cap that has this label.
You can remove the coolant surge tank pressure
capwhen the cooling system, including the
coolant surge tank pressure cap and upper radiator
hose, are no longer hot. Turn the pressure cap
slowly counterclockwise (left) about one full turn. If
you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.
5-33

Cleaning the Windshield, Backglass and Wiper
Blades.......................................................5-97
Cleaning Tires................................................5-98
Cleaning Vinyl................................................5-93
Cleaning Wood Panels....................................5-94
Climate Control System
Automatic...................................................3-19
Climate Controls Personalization....................3-25
Outlet Adjustment........................................3-25
Compass Calibration.......................................2-35
Compass Operation.........................................2-35
Compass Variance..........................................2-36
Content Theft-Deferrent....................................2-16
Control of a Vehicle.......................................... 4-6
Coolant
Engine Temperature Gage............................3-35
Heater, Engine............................................2-21
Surge Tank Pressure Cap.............................5-27
Cooling System..............................................5-30
Corner Roof Marker Lamps..............................5-55
Crossing Obstacles.........................................4-30
Cruise Control.................................................. 3-9
Cruise Control Light........................................3-42
Current and Past Model Order Forms................7-12
Customer Assistance Information
Courtesy Transportation.................................. 7-7
Customer Assistance for Text Telephone (TTY)
Users....................................................... 7-4
Customer Assistance Offices........................... 7-4Customer Assistance Information (cont.)
Customer Satisfaction Procedure..................... 7-2
GM Mobility Program for Persons with
Disabilities................................................ 7-5
Reporting Safety Defects to General Motors....7-10
Reporting Safety Defects to the Canadian
Government............................................7-10
Reporting Safety Defects to the United States
Government............................................7-10
Roadside Assistance Program......................... 7-5
Service Publications Ordering Information........7-11
D
Daytime Running Lamps..................................3-15
Defensive Driving............................................. 4-2
Defogging and Defrosting.................................3-24
Delayed Locking............................................... 2-9
Dinghy Towing................................................4-66
Doing Your Own Service Work........................... 5-4
Dolly Towing..................................................4-66
Dome Lamps.................................................3-17
Door
Delayed Locking........................................... 2-9
Locks.......................................................... 2-7
Power Door Locks......................................... 2-8
Programmable Automatic Door Locks............... 2-9
Rear Door Security Locks.............................2-11
4

Driver
Position, Safety Belt.....................................1-22
DRIVER DOOR AJAR.....................................3-60
Driver Information Center (DIC).........................3-44
DIC Operation and Displays..........................3-44
DIC Warnings and Messages........................3-56
Driving
At Night.....................................................4-41
City...........................................................4-46
Defensive..................................................... 4-2
Drunken....................................................... 4-3
Freeway.....................................................4-47
Hill and Mountain Roads..............................4-50
In Rain and on Wet Roads...........................4-43
Off-Road....................................................4-17
Winter........................................................4-52
Driving Across an Incline..................................4-36
Driving Downhill..............................................4-35
Driving in Mud, Sand, Snow or Ice....................4-39
Driving in Water..............................................4-40
Driving On Grades..........................................4-83
Driving on Off-Road Hills.................................4-31
Driving on Snow or Ice....................................4-52
Driving Through Deep Standing Water...............4-45
Driving Through Flowing Water.........................4-45
Driving Uphill..................................................4-32
Driving with a Trailer.......................................4-81E
Easy Exit Seat...............................................2-53
Electrical System
Add-On Equipment.....................................5-101
Fuses and Circuit Breakers.........................5-102
Power Windows and Other Power Options....5-102
Windshield Wiper Fuses.............................5-102
Electronically Controlled Air Suspension System....4-74
Emissions Inspection and Maintenance
Programs...................................................3-40
Engine
Air Cleaner/Filter.........................................5-19
Battery.......................................................5-42
Check and Service Engine Soon Light............3-38
Coolant......................................................5-24
Coolant Heater............................................2-21
Coolant Temperature Gage...........................3-35
Drive Belt Routing.......................................6-15
Engine Compartment Overview......................5-12
Exhaust.....................................................2-33
Fan Noise..................................................5-35
Oil .............................................................5-14
Overheating................................................5-27
Starting......................................................2-20
ENGINE COOLANT HOT.................................3-57
Engine Oil Additives........................................5-17
5

Sunroof.........................................................2-50
Suspension....................................................4-74
T
Tachometer....................................................3-28
Taillamps.......................................................5-57
Temperature Display........................................2-35
Testing the Alarm............................................2-17
Theft-Deterrent, Radio.....................................3-88
Theft-Deterrent Systems...................................2-16
Content Theft-Deterrent................................2-16
Passlock
®...................................................2-18
Third Row Seat..............................................1-10
TIGHTEN FUEL CAP......................................3-59
Tilt Wheel........................................................ 3-5
Tilting the Seat...............................................1-11
Tire Sidewall Labeling......................................5-60
Tire Size.......................................................5-64
Tire Terminology and Denitions........................5-65
Tires.............................................................5-60
Buying New Tires........................................5-71
Chains.......................................................5-75
Changing a Flat Tire....................................5-79
If a Tire Goes Flat.......................................5-78
Ination - Tire Pressure................................5-68
Inspection and Rotation................................5-69
Spare Tire..................................................5-92
Uniform Tire Quality Grading.........................5-72Tires (cont.)
Wheel Alignment and Tire Balance.................5-73
Wheel Replacement.....................................5-74
When It Is Time for New Tires......................5-70
To Use the Engine Coolant Heater....................2-21
Top Strap......................................................1-48
Top Strap Anchor Location...............................1-49
Torque Lock...................................................2-32
Total Weight on Your Vehicle’s Tires..................4-79
Tow/Haul Mode...............................................2-25
Tow/Haul Mode Light.......................................3-42
Towing
Recreational Vehicle.....................................4-65
Towing a Trailer..........................................4-75
Your Vehicle...............................................4-65
Traction
Control System (TCS).................................... 4-9
Off Light.....................................................3-35
TRACTION ACTIVE........................................3-59
Trailer Recommendations.................................4-75
Trailer Brakes.................................................4-81
Trailer Wiring Harness.....................................4-84
TRANS HOT IDLE ENGINE.............................3-60
Transfer Case................................................5-48
Transfer Case Buttons.....................................2-25
Transmission
Fluid, Automatic...........................................5-21
Temperature Gage.......................................3-36
14