What if my car turn on but the brake lamp turns on?

1. Check the brake fluid level. If the brake fluid level is low, it can cause the brake light to come on. Check the brake fluid reservoir, which is usually located under the hood near the master cylinder. The fluid should be at the "full" mark. If it is low, add brake fluid that is compatible with your vehicle. Brake fluid can cause paint damage - be very careful around your car's paint.

2. Inspect the brake pads. If the brake pads are worn out, they can also cause the brake light to come on. Check the brake pads by removing the wheels and inspecting the thickness of the pads. If the pads are less than 1/4 inch thick, they need to be replaced.

3. Check the brake rotors. If the brake rotors are warped or damaged, they can also cause the brake light to come on. Inspect the brake rotors by removing the wheels and looking at the surface of the rotors. If the rotors are warped or damaged, they need to be replaced.

4. Check the brake lines. If the brake lines are leaking or damaged, they can also cause the brake light to come on. Inspect the brake lines by looking for any signs of leaks or damage. If you find any leaks or damage, the brake lines need to be repaired or replaced.

5. Have the brake system inspected by a qualified mechanic. If you are not comfortable checking the brake system yourself, you can have it inspected by a qualified mechanic. The mechanic will be able to identify the source of the problem and recommend the necessary repairs.