Hummer 2010 H3 - Manual (Page 126)

5-12 Instruments and Controls
It should go out once the engine
starts. If it stays on, or comes on
while driving, there could be a
problem with the charging system.
A charging system message in the
Driver Information Center (DIC)
may also appear. See Battery
Voltage and Charging Messages on
page 5‑21 for more information.
This light could indicate that there
are problems with a generator drive
belt, or that there is an electrical
problem. Have it checked right
away. If the vehicle must be driven a
short distance with the light on, turn
off all the accessories, such as the
radio and air conditioner.
Malfunction
Indicator Lamp
A computer system called OBD II
(On-Board Diagnostics-Second
Generation) monitors operation of
the fuel, ignition, and emission
control systems. It ensures that
emissions are at acceptable levels
for the life of the vehicle, helping to
produce a cleaner environment.
This light comes on when the
ignition is on, but the engine is not
running, as a check to show it is
working. If it does not, have the
vehicle serviced by your dealer.
If the check engine light comes on
and stays on, while the engine is
running, this indicates that there is
an OBD II problem and service is
required.
Malfunctions often are indicated by
the system before any problem is
apparent. Being aware of the light
can prevent more serious damage
to the vehicle. This system assists
the service technician in correctly
diagnosing any malfunction.
Notice: If the vehicle is
continually driven with this light
on, after a while, the emission
controls might not work as well,
the vehicle's fuel economy might
not be as good, and the engine
might not run as smoothly. This
could lead to costly repairs that
might not be covered by the
vehicle warranty.
Notice: Modifications made to the
engine, transmission, exhaust,
intake, or fuel system of the
vehicle or the replacement of
the original tires with other
than those of the same Tire
Performance Criteria (TPC) can
affect the vehicle's emission
controls and can cause this light
to come on. Modifications to
these systems could lead to
costly repairs not covered by
the vehicle warranty. This
could also result in a failure
to pass a required Emission
Inspection/Maintenance test.
See Accessories and
Modifications on page 10‑3.