Are you talking about the warning light in the lower center of the instrument panel that says, "Brake"? If so, that is not the warning light for a failed bulb. There is a separate bulb failure warning light on the lower far right side of the instrument display. The "Brake" warning light serves two purposes: (1) It illuminates if the emergency brake is applied and the ignition key is ON, and (2) it illuminates if the level in the brake fluid reservoir approaches the Minimum level or if the level sensor is defective. I've been dealing with the intermittent Brake warning light for several weeks and finally got clued in from a post on another forum. As you wear down your brake pads, the fluid level will drop. Check your level and if it's near the Minimum mark, add a little DOT 3 fluid to bring it up to Full and see if the mystery Brake light doesn't go back into hiding.
Hope this helps.
