If your vehicle has power door locks, it will have this feature. If you press the power door lock switch when the key is in the ignition and any door is open, all the doors will lock and the driver's door will unlock.
Be sure to remove the key from the ignition when locking your vehicle.
The lockout protection can be overridden by pressing and holding the power door lock in the lock position for three seconds.
Rear Door Security Locks (Sedan)
TrunkChevrolet Cobalt Service & Repair Manual. General Service
Two basic types of power assist
mechanisms are used: vacuum assist diaphragm assemblies, which use engine
vacuum or in some cases vacuum pressure developed by an external vacuum
pump. The second type is a hydraulic pressure assist mechanism, which use
pressure developed by an ...