2008 GMC Sierra 1500 Pickup Owner's Manual - Page 146

Windshield Washer Heated Windshield Washer For vehicles with the heated windshield washer fluid system it can be used to help clear ice, snow, tree sap, or bugs from your windshield. The button is located in the switchbank under the climate controls. {CAUTION: In freezing weather, do not use your washer until the windshield is warmed. Otherwise the washer fluid can form ice on the windshield, blocking your vision. L(Washer Fluid): Push the paddle marked with the windshield washer symbol at the top of the multifunction lever, to spray washer fluid on the windshield. The wipers clear the window and then either stop or return to the preset speed. Push the heated washer fluid button to activate the heated windshield washer fluid system. The indicator light will flash. This activation initiates four heated wash/wipe cycles. The first heated wash/wipe cycle may take up to 40 seconds to occur, depending on outside temperature. After the first wash/wipe cycle, it may take up to 20 seconds for each of the remaining cycles to begin. Press the button again to turn off the heated windshield washer fluid system or it will automatically turn off after four wipe cycles have been completed. When the heated windshield washer fluid system is activated under certain outside temperature conditions, steam may flow out of the washer nozzles for a short period of time before washer fluid is sprayed. This is a normal condition. 3-10