Arteon's Spongy Brakes Point to Low Fluid Mystery

Had a very similar issue with my Passat last year (pretty much the same brake system design as the Arteon). With some experience working on cars, I recognized these classic symptoms of brake system problems. The spongy brake pedal combined with low brake fluid typically indicates either a leak in the brake lines or worn brake components. In my case, a brake inspection revealed worn brake pads and slightly corroded brake lines that were causing a slow leak. Took it to my regular workshop where they did a complete brake fluid replacement, replaced the brake lines, and installed new brake pads. Total repair time was about 4 hours and cost me 480€. The brake pedal felt firm again after the repair and has been working perfectly since. What year is your Arteon and how many miles/kilometers has it done? This info would help determine if your brake components might be due for replacement. Also, when was your last brake fluid replacement? Regular brake fluid changes every 2 years are recommended to prevent moisture buildup in the system. I strongly suggest having a professional brake inspection done soon, as brake issues should never be ignored. They can do a proper pressure test to identify any leaks in the system.

Just had my 35000km service done recently. After reading your detailed explanation, I suspect I might be facing a similar issue. The symptoms match exactly, especially the spongy brake pedal feel that started suddenly. Good to know that brake line corrosion could be a potential cause, as our brake systems are indeed similar. The brake fluid has never been replaced since I got the car new in 2022, so perhaps its time for the first change. Thanks for sharing the repair details and costs, helps set expectations for the workshop visit Ill schedule this week. A proper brake system inspection makes sense, especially since brake safety isnt something to take chances with.

Thanks for the update. Based on the mileage and age of your Arteon, its less likely to be corrosion like in my case, but the warning signs are identical. A 2022 model with 35000km should still have plenty of life in the brake components. Since your brake fluid has never been replaced, thats likely the primary issue. Even on newer vehicles, the brake fluid can absorb moisture over time, leading to that spongy pedal feel you described. The low fluid level in the master cylinder combined with these symptoms often points to either fluid degradation or a minor leak. The brake system inspection I had cost about 60€, but it was worth it for peace of mind. They should check the brake lines, master cylinder, and all connection points for potential leaks. Make sure they also test the brake fluid quality, contaminated fluid can cause similar symptoms even in newer vehicles. Would be interested to hear what they find during the inspection. The fix might be as simple as a brake fluid replacement, which would be considerably less expensive than the brake line replacement I needed on my older model.

Appreciate the thorough response and sharing your similar experience. Just got back from the workshop and wanted to close the loop. You were spot on, it turned out to be primarily a brake fluid issue. The warning light came on during my drive to the shop, which added some urgency. The inspection revealed moisture contamination in the brake fluid, causing that spongy brake pedal feeling. They did a complete brake fluid replacement and thoroughly checked the brake system. No leaks or worn components found, which makes sense given the cars age. The brake lines and other components were all in good condition. Total cost came to 120€ including the inspection and fluid replacement. The brake pedal feel is back to normal now, firm and consistent. The whole service took about 2 hours. They recommended sticking to the 2-year brake fluid replacement interval going forward, which seems reasonable after this experience. Really glad it wasnt anything more serious like brake line corrosion. Good reminder that even newer cars need regular brake fluid maintenance to keep the brake system working properly.