What is an indicator of a malfunction in the braking system?

A soft brake pedal feel is indicative of a malfunction in the braking system because it often points to issues such as air in the brake lines, a hydraulic fluid leak, or a malfunctioning master cylinder. In a properly functioning braking system, the pedal should have a firm and responsive feel when pressure is applied. When the brake pedal feels soft or spongy, it suggests that the braking force is not effectively transferring, which can lead to decreased stopping power and potential safety hazards.

High fuel consumption, an illuminated check engine light, and engine sputtering represent symptoms related to other vehicle systems, primarily the engine and fuel system, rather than directly indicating problems with the braking system. These conditions do not reliably signal issues with how the brakes operate or respond, making them less relevant when diagnosing braking system malfunctions.