GMC Sierra Denali Owner's Manual page 139

Fog Lamps
You can use your vehicle's fog lamps for better vision in
foggy or misty conditions.
The fog lamp button is
located on the left side of
your instrument panel.
Your parking lamps and/or low-beam headlamps must
be on for your fog lamps to work.
Press the button to turn the fog lamps on while the
headlamps are on. Press the button again to turn them
off. An indicator light will glow in the button when
the fog lamps are on.
Remember, fog lamps alone will not give off as much
light as your headlamps. Never use the fog lamps in the
dark without turning on the headlamps.
The fog lamps will go off whenever the high-beam
headlamps come on. When the high beams go off, the
fog lamps will come on again.
The fog lamps will be cancelled after the ignition is
turned off. If you still want to use the fog lamps after you
restart the vehicle, press the fog lamp button again.
Cargo Lamp
The cargo lamp button is
located on the left side of
the instrument panel.
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Press the button to turn
the cargo lamp on.
Press the button again to
turn it off.
An indicator light on the instrument panel cluster will
illuminate when the cargo lamp is turned on, and
the ignition key is turned to RUN.
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