GMC 2001 Sierra - Manual (Page 386)

6-44
Headlamps
1. Remove the two pins on the top of the headlamp
assembly. To remove the pins, turn the outer pin
outward and pull it straight up. To remove the inner
pin, turn it inward and pull it straight up.
A. Low - Beam Headlamp
B. High - Beam Headlamp
2. Pull the headlamp lens assembly out.
3. Unplug the electrical connector.
4. Turn the old bulb counterclockwise and remove it
from the headlamp lens assembly.
5. Put the new bulb into the lens assembly and turn it
clockwise until it is tight. Use care not to touch the
bulb with your fingers or hands.
6. Plug in the electrical connector.
7. Put the headlamp lens assembly back into the
vehicle. Install and tighten the two pins.