You are going to have to replace the entire Headlamp Assembly, very expensive.
remove cap of the back of your light to expose the bulb. then remove the bulb from the head light. leave for a couple of hours to let moisture evaporate. or do the above and use a bit of kitchen roll to dab up the moisture being care full not to damage/scrape the reflective surface of the light replace bulbs when condensation disappears hope this helps
In the head liner right by the dome light and sun roof control
Remove the head light cover plate, then remove head light braket, once you have done that pull the light out and un-plug it.
To change the interior light in a 2002 Lexus LS430, first, locate the light fixture you want to replace. Use a flat-head screwdriver to gently pry off the cover, being cautious not to damage it. Remove the old bulb by twisting it out or pulling it straight out, then insert the new bulb in the same position. Finally, snap the cover back into place to complete the replacement.
HOW DO I CHANGE LIGHT BULBS
The headlight assembly does not need to be removed in order to change a light bulb. Take hold of the light bulb connector. Push the connector in and turn to the left at the same time. The light bulb will come out.
The 2012 Lexus IS-350 has 37.2 in. of front head room.
The 2009 Lexus IS-F has 37.2 in. of front head room.
The 2010 Lexus IS-350 has 36.7 in. of rear head room.
The 2013 Lexus IS-250 has 37.2 in. of front head room.
The 2013 Lexus IS-350 has 36.7 in. of rear head room.
The 2008 Lexus IS-350 has 36.7 in. of rear head room.