my g/fs teg does this. Ive read on h-t that its either

1. Brake fluid is low like mentioned above
2. The sensor on the cap where you put brake fluid in is bad.
or 3. Loose connectiong somewhre in ebrake area.

To test number 2 I read you just unplug the connector(s) near the top bo the cap that are wrapped in rubber. If the light turns off when unplug this the sensor in the cap is the problem. This problem just started for her so its somethign im reading up on so i can fix it this weekend.