Cadillac 2012 CTS Owner's Manual page 350

5. Pull the old bulb from the lamp
housing keeping the bulb
straight as you pull it out.
6. Install a new bulb.
7. Reinstall the electrical connector
by pushing in the two plastic
clips.
8. Push the bulb socket into the
lamp housing and turn the
socket one quarter turn
clockwise.
To replace one of these bulbs:
1. Push the tab to remove the
license plate lamp.
2. Turn the license plate lamp
assembly down to remove it.
3. Turn the socket
counterclockwise and remove it.
4. Pull the bulb straight out to
remove it.
5. Push the new bulb straight into
the socket.
6. Reverse Steps 1 through 3 to
reinstall the license plate lamp
assembly.
To replace one of these bulbs:
1. Open the liftgate. See
for more
information.
2. Push the left end of the lamp
assembly toward the right.
3. Turn the lamp assembly down to
remove it from the liftgate.