GMC 2006 Sierra - Manual (Page 228)

Four-Wheel-Drive Light
The four-wheel-drive
indicator will light up when
you shift a manual transfer
case into four-wheel drive
and the front axle engages.
Some delay between shifting and the indicator’s lighting
is normal.
See Four-Wheel Drive on page 2-38 for more
information.
Tow/Haul Mode Light
This light is displayed
when the Tow/Haul mode
has been activated.
For more information, see Tow/Haul Mode on page 2-31.
Cargo Lamp Light
This light will come on
when the cargo lamp is in
use. For more information
see Cargo Lamp on
page 3-19.
3-50