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 Service & Repair Manual. Description
The TPMS (Tire Pressure Monitor
System) warns the driver when a significant loss or gain of tire pressure
occurs in any of the four tires, and allows the driver to display the individual
tire pressures and the locations on the DIC (Driver Information Center)
display. The syste ...