The light could be on due to:
* Low brake fluid: This is the most common cause. Check your brake fluid reservoir (usually a clear plastic container near the master cylinder under the hood). If it's low, add DOT 3 brake fluid (never exceed the maximum fill line). The light *should* go out once the fluid level is corrected. If it remains on after adding fluid, there's a leak somewhere in the brake system that needs to be addressed by a mechanic.
* Brake pad wear: Worn brake pads trigger the warning light. This requires replacement of the pads. Once new pads are installed, the light might go out automatically after a short drive, or it might require a scan tool to clear.
* Parking brake engaged: Make sure your parking brake is fully released.
* ABS system malfunction: The Anti-lock Braking System (ABS) shares the same warning light in some models. A problem within the ABS system will trigger the light. This requires a diagnostic scan tool to pinpoint the problem; a mechanic will be needed.
* Other brake system problems: There could be issues with the brake system's sensors, wires, or other components. A diagnostic scan tool is necessary to find the culprit.
In short: You don't "reset" the light; you fix the underlying problem causing it. If adding brake fluid doesn't solve the issue, you must have a mechanic diagnose the problem using a scan tool. Ignoring a brake warning light is extremely dangerous. Have your vehicle inspected immediately.
