slowcelica

So I'm trying to figure out why my high beams don't work, checked the fuses in the bay and they were ok. Changed out the lever and switch and it was not that, so I opened the panel next to the fog mirror control and there is a big whit plug that is unplugged, does anyone know what that is for? What else can I check, if the lights are off I can flash my lows by pulling the light lever. But with the lights on the highs won't come on, the high beam indicator in the gauge cluster doesn't light up either.