If your changing D2S Bulbs buy 2 of them because mixing them they never match, I had a 172 with xenon lights and in 12 years only changed them when one bulb went. I rushed out and bought a replacement but it never matched the other so I tracked down the original Philips 4800K (white light) bulbs for about £80. The higher the K rating the more blue the light ( I like white light and car wheels should be silver) I remember the guys at the dealers when I bought the car said the bulbs at that time were £126 each. But the bulbs never faded over time (30 - 202,000 miles) you need to see what lights you have first projectors or xenons the xenons take a few seconds to brighten up when turned on and you can see the auto level lift them as the car is started also if the car stalls or you turn them off and on quickly my 172 had a habit of turning on one then the other the next time until they cooled for 20 seconds which was fun at mot time so the government centres here ask in a certain order full beam first so I used the flasher, then dip so I turned them on (xenon was the dip beam) then they asked for full beam again for level test and that was that, I had to appeal one time for a fail the guy said at night driving and you turned the lights off and they did not relight was dangerous to which I replied I had full beam and if you turned your lights off you disserved to crash the test centre manager allowed it to pass. After that I disabled auto headlights entering the mot centre and booked during daylight hours to make sure the bulbs were not hot before entering the test lane.
