Circuit Description
WARNING: This page is about a different car, the 2003 Buick Regal, 2003 Buick Century, 2002 Buick Regal, and 2002 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
The brake fluid level switch monitors the level of brake fluid in the master cylinder. When the Instrument Panel Cluster (IPC) sees the brake fluid level switch input grounded, it turns on the Red brake indicator and sends a serial data message to the Electronic Brake Control Module (EBCM) that tells the EBCM that the brake fluid level is low.