GMC 2001 Sierra 1500 Pickup Owner's Manual page 151

Electric Outside Rearview Mirrors
(If Equipped)
Move the upper control to the left or right to choose the
mirror you want to adjust, then press the arrows on the
lower control pad to adjust the mirror.
2-68
The control is located on
the driver's door armrest.
Heated Outside Rearview Mirrors
(If Equipped)
The outside rearview mirrors with this feature have a
defrost mode.
To turn on the defrost feature, press the rear window
defogger button. See "Rear Window Defogger" in the
Index for further information.
Convex Outside Mirror
Your passenger's side mirror may be convex. A convex
mirror's surface is curved so you can see more from the
driver's seat.
CAUTION:
A convex mirror can make things (like other
vehicles) look farther away than they really are.
If you cut too sharply into the right lane, you
could hit a vehicle on your right. Check your
inside mirror or glance over your shoulder before
changing lanes.