Buick Verano Owner's Manual page 278

A. Taillamp
B. Turn Signal Lamp
C. Stoplamp/Taillamp
To replace any one of these bulbs:
1. Open the trunk.
2. Remove the push pins securing
the trunk trim.
3. Pull the trunk lining away from
the taillamp assembly.
4. Turn the bulb socket
counterclockwise to remove it
from the rear taillamp assembly.
5. Pull the bulb straight out to
remove it from the bulb socket.
6. Push the new bulb into the
socket.
7. Push the bulb socket straight in
and turn it clockwise to lock it
into place.
8. Reinstall the trunk trim.
9. Reinstall the push pins.
To replace one of these bulbs:
1. Push the left end of the lamp
assembly toward the right.
2. Turn the lamp assembly down to
remove it from the fascia.