What ballast do I need for h7r bulbs as i've just bought one off ebay which states its for d2s/d2r bulbs. Im guessing the new one i've bought is faulty as it won't work at all. I thought as long as I get a 35w, 12v unit id be ok. I also don't know the difference between normal and canbus ballasts.....do canbus ballasts have the warning canceller built in rather than a seperate plug? Cheers.