GMC 2014 Yukon/Yukon XL Owner's Manual page 368

For the proper type of replacement
bulbs, see
.
For any bulb changing procedure
not listed in this section, contact
your dealer.
Halogen bulbs have pressurized
gas inside and can burst if you
drop or scratch the bulb. You or
others could be injured. Be sure
to read and follow the instructions
on the bulb package.
A. Stoplamp/Taillamp
B. Taillamp/Turn Signal Lamp
C. Sidemarker Lamp
D. Back-up Lamp
To replace one of these bulbs:
1. Open the liftgate. See
.
2. Remove the two screws from the
taillamp assembly.
3. Pull the taillamp assembly
rearward until you disengage the
inner pins on the taillamp
assembly from the vehicle.
4. Turn the bulb socket
counterclockwise to remove it
from the taillamp assembly.
5. Pull the old bulb straight out
from the bulb socket.
6. Press a new bulb into the bulb
socket.