GMC 2011 Sierra - Manual (Page 167)

Black plate (19,1) GMC Sierra Owner Manual - 2011
Instruments and Controls 5-19
When the engine is running, this
gauge shows the condition of the
charging system. The gauge can
transition from a higher to lower or
a lower to higher reading. This is
normal. If the vehicle is operating
outside the normal operating range,
the charging system light comes
on. See Charging System Light on
page 5‑24 for more information.
The voltmeter gauge may also read
lower when in fuel economy mode.
This is normal.
Readings outside the normal
operating range can also occur
when a large number of electrical
accessories are operating in
the vehicle and the engine is
left idling for an extended period.
This condition is normal since the
charging system is not able to
provide full power at engine idle.
As engine speeds are increased,
this condition should correct itself
as higher engine speeds allow the
charging system to create maximum
power.
The vehicle can only be driven for a
short time with the readings outside
the normal operating range. If the
vehicle must be driven, turn off all
accessories, such as the radio and
air conditioner.
Readings outside the normal
operating range indicate a possible
problem in the electrical system.
Have the vehicle serviced as soon
as possible.
Safety Belt Reminders
Driver Safety Belt Reminder
Light
When the engine is started, a chime
sounds for several seconds to
remind a driver to fasten the safety
belt, unless the driver safety belt is
already buckled.
The safety belt light flashes for
several seconds, then comes on
solid for several more.
This chime and light sequence
are repeated if the driver remains
unbuckled and the vehicle is in
motion. If the driver safety belt is
already buckled, neither the chime
nor the light comes on.