Got stopped by a policeman for having a headlight out in my 2007 Lexus LS460L. Sure enough, the driver's side low beam was out. Good guy, no ticket, just a warning. I turned off lights, switched them back on, and the light came on bright as ever. Now, when I drive at night the light will stay on for about 15 minutes of driving (sometimes less) and then it cuts out. Should I replace the bulb (which obviously only works "part time") or is there some other electrical issue causing the light to go out? Sure would appreciate some advice before I get to the garage.