I have a 2004 c4s and have noticed when I turn on my headlights that my passenger headlight sometimes won't turn on . Sometimes I notice it kind of flicker then turns on , sometimes nothing. When I turn the headlight switch off and on sometimes it works sometime it doesn't. I already tried resetting the headlight but it still does it. Is this a problem with the switch or is ballast going bad. Any advice is helpful . Thanks guys . Peace!

 

check the wiring harness. it might be a bad ground.

 

The connector problem! I need to push it firmly and get some screw to secure it, and my headlight doing ok now