The site builder lists this within the description:<p>"A twilight sensor disengages the system during daylight to extend its life span."<p>But this wasn't the case with my '06 S40 - they stayed on all the time, which was a little annoying.<p>Thanks!
That is refering to the active component of the Bi-Xenon's the twilight sensor disables the turning of the headlights during daylight the DRL's are always on unless you put the light switch into parking light position.
Swung by the dealer and asked the same question. If you have xenons then your DRL's are xenon all the time. The only way to turn it "off" would be to have it in the parking lights pos. The only thing different from 0 position, headlights, ABL is the output (According to service tech). It's my understanding that the twilight sensor controls when the ABL's start working.