GMC 2010 Yukon/Yukon XL Owner's Manual page 239

Certain accessory plugs may not be compatible to
the accessory power outlet and could result in blown
adapter or vehicle fuses. If you experience a problem,
see your dealer for additional information on the
accessory power plugs.
When adding electrical equipment, be sure to follow
the proper installation instructions included with the
equipment. Do not use equipment exceeding the
maximum amperage rating of 20 amperes.
The front ashtray is located near the center of the
instrument panel or on the front console, if equipped.
Pull on the ashtray door to open it.
To remove the front ashtray pull the ashtray up.
To use the cigarette lighter, push it in all the way, and let
go. When it is ready, it will pop back out by itself.
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