if you have HIDs then check your bulbs and ballast if not then check whatever kind of bulb you have in there. if it's neither then check your fuse box and look under the cover to see which fuse it is for your low beams.
I thought relays were just low voltage switches. Failure of both low beams would indicate your problem is a fuse, rather than bulbs or a relay. If you've modified your lights, look there after checking your fuses.
Boycotting Exxon/Mobil since 1989, BP/ARCO/Amoco since 2010
Have you ever noticed that anybody driving slower than you is an idiot, and anyone going faster than you is a maniac? George Carlin
2006 Scion xB R.S. 3.0. 5MT 49.4 mpg avg over 30,375 miles. 176% of '08 EPA
Best flat drive 94.5 mpg for 10.1 mi
Longest tank 1033 km (642 mi) on 10.56 gal = 60.8 mpg