BMW X3 Radiator Fan Failure Causing Engine Overheat

Hey there! I had similar issues with my 2006 BMW X5 3.0i last year. When my speed sensor went bad, it messed with the radiator fan control module, causing the fan not to engage. The check engine light came on just like yours. Initially thought it was just the fan, but my mechanic found that the speed sensor was sending incorrect signals to the ECU. This prevented the cooling system from working properly. It was a serious issue that needed immediate attention to prevent engine damage. The repair involved replacing both the speed sensor and cleaning the connector pins. After the fix, the fan kicked in normally again and the engine temperature stayed steady. The check engine light cleared up too. Definitely get it checked soon, these symptoms shouldn't be ignored, especially in BMWs. The cooling system is pretty critical, and problems can escalate quickly if left unaddressed. Hope this helps!

Thanks for sharing your experience! That's really helpful info and sounds exactly like what I'm dealing with. Just curious, do you remember roughly how much you ended up paying for the whole repair job? And has everything been running smoothly since then, or did you run into any other cooling system issues? Really appreciate your input!

Hey again! Glad I could help! Since you asked, I paid exactly 250 € to get the speed sensor replaced, and honestly, it was money well spent. The mechanic also found and fixed the defective radiator fan during the inspection, which was a bonus. The best part? Everything's been running like a charm since the repair! No more overheating issues, the fan kicks in exactly when it should, and the engine temperature stays perfectly normal. It's such a relief not having to constantly watch that temperature gauge anymore. Haven't had a single cooling system problem since getting it fixed, it's been smooth sailing all the way. My X5 is running as good as new now. Really glad I didn't wait too long to get it checked out. When these cooling issues pop up, it's definitely worth getting them sorted quickly to avoid any bigger problems down the line. Feel free to ask if you need any other info about the repair process!

Thanks for all those details! I actually bit the bullet and took my X3 to a new mechanic yesterday. Turned out you were spot on, it was the speed sensor causing the fan issues. Cost me a bit more than yours at 350 €, but they did a thorough job and even gave the cooling system a full inspection. Had to wait around for a few hours while they worked on it, but honestly, the peace of mind was worth it. Took it for a test drive right after, and what a difference! The fan's working perfectly now, engine temp is staying steady, and that annoying check engine light is finally gone. Really glad I asked here first, your experience helped me know what to expect and made me feel more confident about getting it fixed. Thanks again for sharing your story, definitely saved me some stress!