A bulb replacement did nothing to fix a headlight outage on my 2011 x5, on the right side.Is the ballast or control module next? Are they both accessible through the wheelwell? Which one has the 3 tab mount vs. the 4 hole mount? Aftermarket or used on any or both? Is there a remedy that converts these 3 component 'nightmares' to a simpler one component halogen system?