To replace one of these bulbs:

1. Remove the two screws holding each of the license plate lamps.
2. Turn and pull the license plate lamp toward you through the opening.
3. Turn the bulb socket counterclockwise and pull the bulb straight out of the socket.
4. Install the new bulb.
5. Push the bulb straight into the socket and turn clockwise to reinstall.
6. Push and turn the license plate lamp away from you through the opening.
7. Reinstall the two screws holding the license plate lamp.
Back-Up Lamps (Coupe)
Replacement BulbsChevrolet Cobalt Owners Manual. Back-Up Lamps (Coupe)
To replace a back-up lamp bulb:
1. Open the trunk. See Trunk.
2. Locate the back-up lamp bulb assembly in the
trunk lid.
3. Turn the bulb socket counterclockwise and pull it
out of the lamp assembly.
On vehicles that have a back-up lamp cover, first
remove it by pressing the tab at the to ...