[shorod]

To be clear, you're trying to determine what's causing the red "BRAKE" light to light up, correct, not the amber "ABS" light?

The switch for both the low fluid level and the parking brake lever are normally open switches, and will trigger the Generic Electronic Module (GEM) to light the BRAKE light if they close (to ground). You could check to see if you have a solid path to ground at the appropriate GEM terminals, or disconnect the switches and test for continuity across them. If you have continuity across either of them to ground, that is the likely source for the BRAKE light being on.

I'm not sure of the switch is easily replaceable or if you are expected to buy a new master cylinder. Sounds like a good question for the parts store.

-Rod