GMC 2003 Sierra - Manual (Page 178)

Rear Window Defogger
The Uñes you sa« on the rear wlntiow warm the glass,
The near window defogger uses a warming grid to
rgmove iog from ftie rear window.
Cwt] ^Rear): Press this bullón lo lurrt Ihe rear window
defogger or^ or off. An indicator light fn the button
wHl come on to lei you know thal the rear window
defogger la activatod
The rear window dsfooger wlH automatically turn off
several min ules after the burton is pressed. Pressing the
button whife the defoggsr is running can also turn off
the defogger.
If your vehicle Is equipped with healed mirrors lhi&
button Will actívale iham.
Notice: Don't use anything sharp on the inside of
the rear window. If you do, you could cut or damâge
the warming grid, and the repairs wouldn't be
covered by your warranty» Do not attach a temporary
vehicle license, tapoi a decat or anything similar
lo the defoggar grid.
Outlet Adjustment
Use the air outlets located in the center and on Ihe side
ot your Instrumeni panel to direct The airflow.
Vour vehicle has air outlets that allow you lo adjust Ihe
direction and amount of airflow inside the vehicle
Move the louvers up or down. Use the thumbwheel next
lo or undernealh Ihe ouHet to ctuse the louvers. For
Ihe most efficlenl airflow and lemparalune coolrol, keep
the outlet in Ihe (ully opened position.
Rear seal outlets can be used to adjust airflow toword
either sealing area, (he floor or upward. Move the center
louvers up or [iown to direct ihe airflow»
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