Your 2005 Nissan Altima uses both H1 and 9005 replacement headlights. The H1 headlight is used for the low beam while the 9005 bulb is used for the high beams. However, they will both eventually burn out. When they do, you will need to replace them. Replacement headlights can be purchased form most auto-parts stores. When replacing your headlights, you should replace them as sets. For example, if the high beams burn out, you should replace both high beams. If the low beams fail, you should replace both low-beam headlights.
Difficulty: Moderately Easy
Things You'll Need
H1 replacement headlight
9005 replacement headlight
Open the hood and remove the airbox mounting bolt on the driver's side fender.
Pull the airbox up and away from the fender. Now you will be able to change the headlight bulbs.
Unplug the headlight connector from the back of the headlight bulb that is blown. To do this, squeeze the headlight-connector release tabs and pull the connector off the headlight.
Rotate the headlight counterclockwise and remove it from the headlight-housing assembly.
Insert the new headlight and rotate it clockwise to lock it into the headlight housing. Make sure that you handle the headlight by the plastic collar so that you do not touch the headlight bulb. Touching the bulb can shorten the life of the headlight.
Reconnect the headlight connector to the headlight and replace the airbox. Installation is the reverse of removal.