overheating HUMMER H2 2007 User Guide

Coolant Surge Tank Pressure Cap
Notice:If the pressure cap is not tightly
installed, coolant loss and possible engine
damage may occur. Be sure the cap is properly
and tightly secured.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank. SeeEngine
Compartment Overview on page 402for more
information on location.
Engine Overheating
You will nd a coolant temperature gage on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 213.
In addition, you will nd an ENGINE COOLANT
HOT, ENGINE OVERHEATED and a REDUCED
ENGINE POWER message in the Driver
Information Center (DIC) on the instrument panel.
SeeDIC Warnings and Messages on page 226.
If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
you badly, even if you just open the hood.
Stay away from the engine if you see or
hear steam coming from it. Turn it off and
get everyone away from the vehicle until
it cools down. Wait until there is no sign of
steam or coolant before you open the hood.
If you keep driving when the vehicles
engine is overheated, the liquids in it can
catch re. You or others could be badly
burned. Stop your engine if it overheats,
and get out of the vehicle until the engine
is cool.
SeeOverheated Engine Protection
Operating Mode on page 420for
information on driving to a safe place in
an emergency.
418

Check the coolant level after the system cools
down. Some amount of coolant may be lost due to
overheating.
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.
Notice:Engine damage from running your
engine without coolant is not covered by your
warranty. SeeOverheated Engine Protection
Operating Mode on page 420for 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 could 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.
421

Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and where
to obtain service, see your GM Warranty booklet
for details. For additional information refer to
the tire manufacturer’s booklet included with your
vehicle.
{CAUTION:
Poorly maintained and improperly used
tires are dangerous.
Overloading your vehicle’s tires can
cause overheating as a result of too
much friction. You could have an
air-out and a serious accident. See
Loading Your Vehicle on page 362.
CAUTION: (Continued)
CAUTION: (Continued)

Underinated tires pose the same
danger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
Tire pressure should be checked when
your vehicle’s tires are cold. See
Inflation - Tire Pressure on page 456.
Overinated tires are more likely to be
cut, punctured, or broken by a sudden
impact — such as when you hit a
pothole. Keep tires at the
recommended pressure.
Worn, old tires can cause accidents.
If the tire’s tread is badly worn,
or if your vehicle’s tires have been
damaged, replace them.
448

Electrical System (cont.)
Underhood Fuse Block............................. 507
Windshield Wiper Fuses........................... 503
Electronically Controlled Air Suspension
System.................................................... 372
Engine
Air Cleaner/Filter...................................... 409
Battery..................................................... 431
Check and Service Engine Soon Light........ 215
Coolant.................................................... 415
Coolant Heater......................................... 123
Coolant Temperature Gage...................... 213
Drive Belt Routing.................................... 531
Engine Compartment Overview................ 402
Exhaust................................................... 137
Oil ........................................................... 404
Oil Life System........................................ 407
Overheated Protection Operating Mode...... 420
Overheating............................................. 418
Starting.................................................... 121
Entry/Exit Lighting....................................... 191
Event Data Recorders (EDR)...................... 546
Extender, Safety Belt..................................... 45
Exterior Lamps............................................ 186F
Filter
Engine Air Cleaner................................... 409
Finish Damage............................................ 499
First Aid Kit................................................. 360
Fixed Mast Antenna.................................... 300
Flashers, Hazard Warning........................... 176
Flash-to-Pass.............................................. 180
Flat Tire...................................................... 468
Flat Tire, Changing...................................... 468
Flat Tire, Storing.................................485, 488
Fluid
Automatic Transmission............................ 412
Power Steering........................................ 425
Windshield Washer.................................. 426
Four-Wheel Drive........................................ 438
Four-Wheel Drive, Full-Time........................ 128
Front Axle................................................... 440
Front Mounted Receiver.............................. 360
Fuel............................................................ 394
Additives.................................................. 395
California Fuel.......................................... 395
Filling a Portable Fuel Container.............. 399
560