1998 GMC Yukon Owner's Manual - Page 141

Rear Ashtray To use a rear ashtray, if you have them,pull at the top of the ashtray door to flip the door open. To remove a rear ashtray, press down on the inside tabs and open the door fully. To use the cigarette lighter, push it in all the way, and let go. When it's done heating, itwill pop back by itself. Accessory Power Outlets NOTICE: Holding a cigarette lighter in with your hand while it is heating canmake it overload, damaging the lighter and the heating element. Just push the lighter all the way in and let go. When it's done heating, it will pop back by itself. Two auxiliary power outlets are located near the cigarette lighter. Use these outlets to power mobile telephones or other devices designed operate with to vehicle electrical systems. 2-63