GMC 2003 Sierra - Manual (Page 437)

If your vehicle has one pin on the headlamp
ass^mhly, remove the pin. To remove the pin, turn
ihe pin op and pull iL out sUaighI out.
A. Low-Beam Headlamp
B, HIgh'Eeam Headlamp
2. Pull the headlamp assembly out.
3. Unplug ihe eleciricaJ connector,
4. Turn Ihe old bulb counterclockwise and remove it
from the headlamp assembly.
5. Put [he new bulb into ihe assembly and turn it
clockwise until il is tighi, Use cara net to touch
the bulb with your fingers or harwls*
6. Plug in the eJeclfical connector,
7^ Pul the headlamp assembly back Inlo the vehicler
Install and tighten the Iwopins. 11 your vehicle has
one pin, Inslall II and lurn It Into the Eocklng feature.
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