No matter how full the windshield washer fluid reservoir is the light stays on. This afternoon it turned on and won't turn off. This happen once a few weeks ago when it came on and stayed on until i went to the car wash. The first time the fluid wasn't even low to begin with.

Any ideas what could be the issue and how to fix it? The car is a 2005 1.8t with 85k on it

 

The sensor on the bottle is probably broken. There's a small cable on the bottom of the bottle that connects to it, make sure that is connected.