Hummer 2007 H3 - Manual (Page 338)

Add coolant mixture at the recovery tank, but be
careful not to spill it.
{ 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.
Occasionally check the coolant level in the
radiator. For information on how to add coolant to
the radiator, see Cooling System on page 340.
Radiator 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.
See Engine Compartment Overview on page 322
for more information on location.
Engine Overheating
A coolant temperature gage is on the instrument
panel. See Engine Coolant Temperature Gage
on page 185.
The air conditioning might stop working if the
engine is too hot. This is normal and helps cool
the engine.
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. Just
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 your engine is
overheated, the liquids in it can catch fire.
CAUTION: (Continued)
338