GMC 2004 Sierra - Manual (Page 182)

Auxiliary Roof Mounted Lamp Switch
If your vehicle has this feature, this switch includes
wiring provisions for a dealer or a qualified service
center to install an auxiliary roof lamp.
This switch is located on
the center of the
instrument panel near the
comfort controls.
When the switch wiring is connected to an auxiliary roof
mounted lamp, pressing the switch will activate the lamp
and illuminate an indicator light near the switch. Pressing
the switch again will turn off the roof mounted lamp.
If your vehicle has this switch, your vehicle may have
the snow plow prep package. For further information see
“Snow Plow Prep Package
″
.
Cargo Lamp
The cargo lamp button is
located on the left side of
the instrument panel.
Press the button to turn the cargo lamp on. Press the
button again to turn it off.
An indicator light on the instrument panel will illuminate
when the cargo lamp is turned on and the ignition
key is turned to RUN.
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