Skid Control Buzzer Circuit: Description
WARNING: This page is about a different car, the 2006 Lexus GS 430 and 2006 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
The skid control buzzer sounds while the accumulator pressure is abnormally low or when an abnormality causing low fluid pressure occurs, and then the VSC is activated.