How can you detect that a disc brake system has worn brake pads?

The selected combination is correct because both elements you chose are key indicators of worn brake pads in a disc brake system.

1. Wear marks on the brake pad are designed to visually inform the driver when the pads need replacement. These marks serve as an important safety feature, ensuring that drivers can check their brakes regularly.

2. A very low fill level in the brake fluid reservoir can indicate that the brake pads are worn down. As the pads wear, the brake caliper needs to move more, which can cause the brake fluid level to drop. This is crucial for maintaining proper braking performance and safety.

In Germany, regular vehicle maintenance checks often involve monitoring brake components to ensure compliance with safety regulations. Recognizing these signs can prevent brake failure and enhance road safety, which is a core principle of German traffic laws.