GMC 2007 Sierra - Manual (Page 186)

Outside Power Foldaway Mirrors
If your vehicle is
equipped with this
feature, the controls are
located on the driver’s
door armrest.
Move the upper selector switch to the left or right
to choose the mirror you want to adjust; then
press the dots located on the four-way control pad
to adjust the mirror.
The mirrors may also include a memory function
which works together with the memory seats.
See Memory Seat and Mirrors on page 12 for more
information.
To fold or unfold the mirrors, move the selector
switch, located above the mirror control, to
the middle position. The mirror control will
illuminate. Press the right or left side of the mirror
control to fold or unfold the mirrors. You may
notice the mirror glass adjust as the mirrors fold
in; this is normal. The mirror glass will reposition
itself once the mirrors are unfolded.
If the mirrors are accidentally folded/unfolded
manually, they may shake or flutter at normal
driving speeds and may not stay in the unfolded
position. If this happens, you will need to reset the
mirrors. See “Resetting the Power Foldaway
Mirrors” next.
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