1996 GMC Yukon Owner's Manual - Page 66

Your vehicle has one double-sided key for the D r LOC'; o If you ever lose your key, your dealer will be able to assist you with obtaining a new one. Unlocked doors canbe dangerous. Passengers especially children can easily open the doors and fall out. When a dooris locked, the inside handle won't open it. Outsiders caneasily enter through an unlocked door when you slow down or stop your vehicle. This may notbe so obvious: You increase the chance of being thrown outof the vehicle in a crash if the doors aren'tlocked. Wear safety belts properly, lock your doors, and you will be far better off whenever you drive your vehicle. -- -- There are several ways to lock and unlock your vehicle. From the outside, use your key. 2-2