Spongy Brake Pedal (Soft Pedal)

Air in the hydraulic system is a common cause. Old brake fluid with a lot of water can boil under heavy use and form vapour. Leaking lines, hoses or a worn master cylinder can also cause it. ABS units sometimes need a scan tool procedure to remove trapped air.

Air and vapour compress, unlike brake fluid, so part of the pedal travel is used to squeeze them instead of moving the pads.

Do not drive until the brakes have been checked. Bleeding the brakes and replacing old fluid fixes many cases.