Spongy Brake Pedal on Mercedes SL

Low brake fluid and a spongy pedal usually mean air in the lines or a leak. Check your pads and rotors for wear. Low fluid happens as calipers extend. Inspect brake lines and connections for leaks. Any fluid under the car?

Thanks I will check the pads and rotors. If there's no leak and the pads are worn, could the master cylinder be failing? I've heard that can cause similar issues.

A failing master cylinder is possible, but less likely without complete brake failure. With the mileage and low fluid, worn brakes are most likely. Get it checked professionally, as hydraulic brakes are crucial.

I took it to my mechanic, and you were right. The front pads were shot. New pads and rotors, lines bled, and all is normal. Cost 480€, but worth it. Thanks for the help.