Hi all, it's been nearly a year since I was last on here when I sold my beloved CLK 320 CDI Sport as I needed a bigger / more practical car. Long story short the SUV I bought just wasn't for me and now I'm back in the fold with a C270 CDI Estate (2004). It has the Xenon headlights factory fitted but both dipped beams are not working. I bought the car like this knowing I would need to deal with the issue, to be fair the car was so damn cheap I couldn't turn it down!! I know that the only lights that are HID on the car are the dipped beam so I can still get around on side lights and fogs although this is obviously not ideal. So the seller said one of the lights went out way before the other then he bought 2 new bulbs which didn't work. He was told by a local garage to go out and buy 2 complete new headlights units which for him was uneconomical (well it would be if he bought new!). What I was wondering is what is most likely to be the cause? Ballasts, igniters or wiring issue. Has anyone physically done a step by step test or is it mega common for ballast's to pack up? He was also told that one side power the other side, wasn't sure if that sounded right as I know there is a ballast under each light unit. If anyone has tested them could they let me know how? I have a multi-meter and I know a fair degree about electric and also that capacitors can give you a good old belt so not a total fool with electrical stuff. To be honest I'm thinking of buyer two ballast anyway as they are about £45 each delivered. Any advice much appreciated.