Brake light comes on & ringing as we are going down the road

Hello, a brake warning light coming on can be serious business. It could indicate a problem in the hydraulic brake system, which means your car could fail to stop as commanded. It could also indicate an issue with the anti-lock braking system. It could even mean the parking brake is still engaged. In any case, I would recommend you find a local shop near you to help have a look: http://repairpal.com/lexus-within-10-miles-of-monroe-north-carolina-28110