* Low Brake Fluid: This is the simplest and most important check. Low brake fluid indicates a leak somewhere in the system, which is a serious safety hazard. Check your brake fluid reservoir (usually a clear or translucent container) and top it off if necessary with DOT 3 brake fluid (never use anything else). If it's low, *find the leak immediately* before driving again.
* Brake System Malfunction: A problem with a brake component, such as a faulty wheel speed sensor (common in ABS systems), a failing ABS module, or a problem with the brake pressure modulator, can trigger both lights. These issues are more complex and require professional diagnosis.
* Faulty Wheel Speed Sensor: These sensors monitor wheel rotation speed for the ABS system. A malfunctioning sensor can cause the ABS and brake lights to illuminate. These sensors are relatively inexpensive and easy to replace, but the correct one needs to be identified and the sensor should be checked with a diagnostic tool.
* ABS Module Failure: The ABS module is the "brain" of the anti-lock braking system. A faulty module can cause a multitude of problems, including the illumination of the warning lights. This is usually the most expensive repair.
* Worn Brake Pads/Rotors: While severe wear *might* indirectly contribute (by affecting sensor readings), it's less likely to trigger both lights simultaneously compared to the other causes. Inspect your brake pads and rotors.
* Wiring Issues: Damaged or corroded wiring within the brake system or ABS system can also cause the lights to come on.
What to do:
1. Check brake fluid level immediately. If it's low, stop driving until the leak is found and fixed.
2. Have the vehicle scanned with an OBD-II code reader. This will give you diagnostic trouble codes (DTCs) that pinpoint the problem area. Auto parts stores often offer free code reading services.
3. Consult a qualified mechanic. Based on the code(s) and a thorough inspection, a mechanic can diagnose the issue accurately and perform the necessary repairs.
Ignoring these lights is dangerous. Driving with a malfunctioning braking system significantly increases the risk of an accident. Get it checked out as soon as possible.
