Suburban Headlights Malfunctioning?

[1badbowtie]

I know my rig is a little newer for this Forum, I'm just exploring everyones knowledge out there.

I have a 98 Suburban, 1 headlight went out, so I replaced both low beam bulbs, worked fine for about a week, and now daytime running lights work fine, but when I turn the headlight switch to on, the headlights go out, and the brights don't work either, but if I turn the switch to the off position, the daytime running lights work fine, not sure what this problem could be?? Headlight switch?? Relay?? I sure hope someone out there has had the same problem.

Thanks,

ANDY