GMC 2003 Sierra - Manual (Page 183)

"0 A/C íAír Condhtiúning): Pnsss Ihis bullón lo
manually lum Ihe sir^condilioning system on or off.
VVhsn the syslem Is selectecl, or In AUTO mode
the system will autormatically begin lo cool and
dehumidffy Ihe etr InsEde ol your vehicle^
If you select air conditioning off while m from defrosl, or
defog mode the air torditioning off symbol will Hash
to ilel you know this is not altowecl.
You may nolice a stight change in engine performance
when Ihe air-conditioning compressor shuts off and
turns on again. This is normal,
Í4: {Air Conditioning Off): When you lum the air
condrticning off. this symbol wril appear on ihe display.
When the air condiEioning is selected or in AUTO
rm>de. tha system wilf run ihe air conditioning
aulomalicaily.
Defogging and Defrosting
You can use eitbor delog or front defrost to clear fog or
frost from your windshield. Use the defog mode to
clear the windows cf fog or moisture. Use the tnont
tiefrost button to defrost Ihe Inont windshield.
(Detog); Use this setting to dear the windows of fog
or mcislure. Press the mode button lo setect this
sotting. This setting will dai'iver air to the floor and
windshield ouHets
3-28 --------------------------------------------------------------------
^ (Front Detroat): Press Ihe front defrost button to
defrost the wirdshield. The system will automatleatly
control 1he fan speed if you seleci defrost from AUTO
mode, fl Ihe outside tomperafure is 4CPF (4"C) or warmer,
your air conditioning compressor wiH automaticafly run to
help dehumidify the air and dry the windshieJd.
Rear Window Defogger
Tha [linos you see on the rear window warm Ihe glas"s.
The rear wir^ctow defogger uses a warming grid to
remove fog from the rear window.
Cyi (Rear): Press this button to turn the rear winciow
defogger on or aff. An indicator light in the button
will come on to let you know that fhe rear window
defogger is activated.
The rear window defoggoi- will turn off approHimatoly
10 minutes after the button is pressed. If you need
additfonal warming tima, press the button again.
If you vehicle is equipped with heated minors this button
will aclivale (horn.
Notice: Don’t uso a raior blade or something else
sharp on the it^elde of the rear window. If you
do, you couEd cut or damage ihe defogger and Ihe
repairs would not be covered by your warranty.
Do not attach a temporary vehicle licenser tape, a
decal or enylhing similar to the defogger grid.