BMW 1: Multiple Warning Lights & Spongy Brake Pedal Issue

Hey there! I have some experience with BMWs, having dealt with a similar issue on my 2018 BMW 2-Series (though I also considered the 3-Series at the time). Electrical gremlins can be super frustrating! Had almost identical symptoms, multiple warning lights, including brake and ABS warnings. Turned out to be an undervoltage problem affecting various control modules. My trusted mechanic diagnosed it, and it cost me around 240 Euro to fix, mainly because they had to reset and recalibrate several systems once the voltage issue was sorted. Could be something similar with yours, but I'd need more info to be sure. What's the mileage on your car? Have you noticed any other electrical issues, like dimming lights or slow starter? Also, when exactly did these symptoms start showing up? Let me know and I might be able to share more relevant details from my experience!

Thanks for sharing your experience! My car's at 109114 KM and just had its service done recently. In my case, the symptoms started quite suddenly, just a few days ago during normal driving. Haven't noticed any electrical issues like dimming lights or starting problems, which makes me think it might be different from your situation. The pedal feels spongy and sometimes needs more pressure than usual to brake properly. Did your brake pedal feel similar before finding out it was a voltage issue? Pretty worried about driving it like this, to be honest.

Hey again! Thanks for the additional details about your situation. You know, thinking back to my BMW's issues, the brake pedal behavior was actually quite different from what you're describing. Mine didn't have that spongy feeling you mentioned, it was more of an intermittent stiffness combined with the warning lights. Given what you're saying about the spongy brake pedal and increased pressure needed, I'm actually leaning away from my initial voltage-related guess. This really sounds more like it could be a hydraulic issue in your brake system, possibly air in the lines or a master cylinder problem. When my voltage issue was fixed, it only solved the warning lights, but it seems like you're dealing with an actual physical brake performance problem. I'd strongly suggest getting it checked out ASAP, don't take chances with brakes. My mechanic actually warned me about similar symptoms in other BMWs he'd worked on, and they often turned out to be hydraulic-related. Have you noticed any brake fluid leaks under the car? That might help confirm if it's a hydraulic system issue rather than electrical like mine was. Would be curious to hear what your mechanic finds! Stay safe and let us know how it goes!

Thanks so much for the detailed follow-up! You're right, this does sound quite different from your voltage issue. I just checked under the car and actually noticed a small dark stain that could be brake fluid. That really lines up with what you're saying about it possibly being a hydraulic problem. I've called my mechanic and booked it in for tomorrow morning, definitely not worth risking it with brake issues. They mentioned they'll check the master cylinder and brake lines first, which matches what you suggested. The warning lights are still concerning, but at least we might be getting closer to identifying the real problem. Really appreciate you taking the time to share your experience and help me think this through. I'll be sure to update once I know what's actually causing the problem. Better safe than sorry when it comes to brakes!