1999 GMC Sonoma Owner's Manual - Page 63

yellowblue Power Door Locks (If Equipped) Lockout Prevention To protect you from locking your key in the vehicle, this feature stops the power door locks from locking when the keys are in the ignition and a door is open. 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 the driver's door will unlock. Leaving Your Vehicle If you are leaving the vehicle, take your keys, open your door and set the locks from inside. Then get out and close the door. Keyless Entry System (If Equipped) If your vehicle has power door locks, the 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. If your vehicle has this option, you can lock and unlock your doors from about 3 feet (1 m) up to 30 feet (9 m) away using the remote keyless entry transmitter supplied with your vehicle. Your keyless entry system operates on a radio frequency subject to Federal Communications Commission (FCC) Rules and with Industry Canada. 2-5