Charging System Light; Voltmeter Gage - GMC 2007 Envoy Denali Owner's Manual

Charging System Light

It should go out once the engine is running. If it
stays on, or comes on while you are driving,
you may have a problem with the charging system.
It could indicate that you have problems with a
generator drive belt, or another electrical problem.
Have it checked right away. Driving while this
light is on could drain your battery.
If you must drive a short distance with the light on,
be certain to turn off all your accessories, such
as the radio and air conditioner.
The charging system
light will come on briefly
when you turn on the
ignition, but the
engine is not running,
as a check to show you
it is working.

Voltmeter Gage

When the engine is running, the gage shows the
condition of the charging system. The gage
may transition from a higher to lower or a lower to
higher reading, this is normal. Readings between
the low and high warning zones indicate the
normal operating range. The voltmeter gage may
also read lower when in fuel economy mode.
This is normal.
When your engine is not
running, but the ignition
is in RUN, this gage
displays the battery
voltage in DC volts.
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