hi, recently i have been noticing that while driving at night the right side HID headlight on my RL goes off just like that and when i turn the light switch off and then to "on" position the light turns back on....
any suggestions to what might be causing this phenomenon??..... can't be the switch itself as the left side headlight works fine all the time....thanks in advance

 

could be a bulb, could be a ballast, it happens to many people including my self. If car under warranty you can take it to dealer, otherwise you can buy a D2S bulb on amazon for under $60 and install that yourself.

 

How hard is it to replace the bulb?