2000 GMC Envoy Owner's Manual - Page 67

Power Door Locks Rear Door Security Lock With this feature, you can lock the rear doors so they can't be opened from the inside by passengers. Move the lever up to lock the doors and down to release the door locks. The power door lock switch is located on the armrest. Remove the ignition key and press LOCK to lock all the doors at once. To unlock the doors, press the raised area next to the key symbol. The switch on each rear door works only that door's lock. Lockout Prevention This feature stops the power door locks from locking when the key is in the ignition and a door is open to protect you from locking your key in the vehicle. If the power lock switch is pressed when a door is open and the key is in the ignition, all the doors will lock and then the driver's door will unlock. 2-5