Chevrolet 2005 Colorado Owner's Manual page 316

To replace the bulbs, do the following:
1. Open and support the hood. See Hood Release
on page 5-11.
2. Access the bulb/sockets from the engine
compartment.
3. Turn the bulb socket counterclockwise and pull it
straight out of the headlamp housing.
4. Unplug the electrical connector from the old bulb.
5. Plug in the electrical connector to the new bulb. Use
care not to touch the new bulb with your bare hand,
anything damp or oily.
6. Place the connector with the new bulb into the
headlamp housing and turn it clockwise until it
is tight.
5-48
Sealed Beam Headlamps
To replace the headlamp capsule, do the following:
1. Remove the four retainer screws and the retainer.
2. Pull the headlamp capsule toward you and
unplug the electrical connector from it.
3. Remove the old headlamp capsule.
4. Plug the electrical connector into the new headlamp
capsule.
5. Reverse Steps 1 and 2 to reinstall the headlamp.