To lock the driver door from outside the vehicle, turn the key clockwise. Turn it counterclockwise to unlock.
The Remote Keyless Entry (RKE) transmitter can also be used to lock or unlock the doors.
From the inside, use the manual lock knobs on each door or use the power door locks.
Power Door Locks

This vehicle may have power door locks.
The controls are located
on the driver and front
passenger door armrests.
: Press to unlock the
doors.
: Press to lock the doors.
For more information see:
- Door Locks.
- Power Door Locks.
- Remote Keyless Entry (RKE) System Operation.
Remote Vehicle Start
Trunk ReleaseChevrolet Cobalt Service & Repair Manual. Emission Control System Inspection
Caution: Do not remove any
component of the engine emission control system. Operating the engine without
the engine emission control system intact will reduce fuel economy and engine
ventilation. This will weaken engine performance and shorten engine life.
The vehicle ...