BMW i4 Brake Warning Light: Common Causes & Solutions

Hey there! I have some experience with EVs and their braking systems. I actually had a similar issue with my 2020 BMW iX3 last year (I switched from an i3 before that). The symptoms you're describing sound really familiar. In my case, it turned out the brake pads were quite worn, which triggered the warning system. Took it to my regular workshop, and they confirmed the front and rear brake pads needed replacement. Even though EVs use regenerative braking, the regular brakes still wear down. The whole thing, including labor, set me back about 480 Euro. Before I share more specific details about my repair experience, could you share: How many miles/kilometers are on your i4? Are you noticing any squealing sounds when braking? Does the pedal feel spongy or just different? This would help me better understand if you're dealing with the same issue I had.

Thanks for your detailed response! My i4 has 128550 KM on it and I just had the service done last month. And yes, the brake pedal feels a bit spongy, but no squealing sounds so far. It's more like the pedal needs more pressure than usual to get the same braking effect. The warning light is what really got me worried though. The interesting thing is my regen braking still works perfectly fine, it's just the regular braking that feels off. I'll probably need to get it checked out regardless, but it's good to know about your experience with the brake pads. Did your pedal feel similar before you got it fixed?

Hey again! Thanks for those details, it actually sounds quite different from what I experienced with my brake pads. When I had worn brake pads, the pedal was firm but there was that telling squealing noise. Your spongy pedal combined with the warning light, especially with the extra pressure needed... that does sound more like a hydraulic issue. Come to think of it, even though you just had service done last month, I'd definitely get the brake fluid level checked ASAP. My 's i4 had similar symptoms, spongy pedal, warning lights, and it turned out there was a small leak in one of the brake lines that was causing fluid loss. The service hadn't caught it because it was really subtle at first. I know you mentioned the regen braking works fine, which was the same in my 's case, that's because the regen system is separate from the hydraulic brakes. But definitely don't wait on getting this checked out. I've had my iX3 for a while now and one thing I've learned is that when it comes to brake issues, it's better to be safe than sorry. Would you mind updating us once you find out what's causing it? It would be really helpful for other i4 owners too.

Thanks everyone for the helpful responses. I just got back from the service center and wanted to close the loop on this. Turns out there actually was a slow brake fluid leak from a damaged seal, you were right about the hydraulic issue! They found it during inspection, replaced the faulty seal, topped up the brake fluid, and did a complete brake system bleed. The whole repair came to around €385, which wasn't as bad as I feared. The brake pedal feels normal again, and all warning lights are off. Really glad I didn't wait any longer to get it checked out. The service advisor mentioned that while these issues aren't common in the i4, it's crucial to address brake warning lights immediately, regardless of how the car feels. Thanks again for helping me understand what might be going on. It definitely made me feel more informed when talking to the service center. Just shows how helpful it is to have a community to bounce these issues off of!