I've changed the D1S bulb on the driver's side, and checked the fuse but it's still not working. Actually my mechanic did. Can anybody suggest what the issue might be? Your help would be greatly appreciated.
did you change it because the other 1 stopped working or did you change it because you switched to a diff temp?
if it is because it stopped working you need to test to see if power is going into the ballast, if yes, then the power isnt coming out of the ballast so then your issue would be the ballast.