BMW i3 Temperature Sensor Issues Causing Multiple Failures

Hey there! I had a similar issue with my 2017 BMW i8 (also had experience with a BMW i4). I have some experience working on cars, but mainly basic maintenance stuff. My temperature readings were going crazy, and I faced almost identical symptoms. Took it to my regular workshop last month, and it turned out to be a faulty wiring connection to the ambient temperature sensor. The cables had some corrosion and weren't making proper contact. The mechanic cleaned up the connections and replaced some worn-out wiring. Total bill came to 95 Euro, and it's been working perfectly since then. Could you share more details about your i3? Like when did these issues start, and have you noticed any error messages on the dashboard? Also, does the problem get worse in certain weather conditions? This info would help me understand if you're dealing with the exact same issue I had.

Had my last service about 2 months ago at 96839 KM, and I've started noticing these issues about three weeks ago. The temperature reading fluctuates out of nowhere, sometimes it shows -10 when it's clearly much warmer, and other times it spikes up for no reason. No error messages on the dash yet, but yes, it definitely gets worse in wet weather. Your experience with the wiring issue sounds exactly like what I might be dealing with. Did your mechanic have to remove any specific panels to access the sensor connections? Just trying to get an idea of what I'm looking at repair-wise. Thanks for sharing your experience, it's really helpful to know others have solved similar problems without breaking the bank.

Oh that does sound exactly like what I dealt with! The symptoms match up perfectly, especially that bit about it acting up in wet weather. In my case, the mechanic had to remove the front bumper cover to access the sensor connections, it's a bit tucked away on these i-series BMWs. Not a huge job, but definitely not something I'd want to tackle in my driveway. Interesting that you mentioned the 96839 KM service mark, mine started acting up right around the 95000 KM mark. Could be some sort of common wear point for these models. One thing I forgot to mention in my first reply, before fixing it, my mechanic actually tested the sensor itself, which was totally fine. It was purely a wiring issue, just like I suspected. Since you're having the same wet weather correlation, I'd bet money you're dealing with the same problem. Quick tip though, if you do get it fixed, ask them to apply some dielectric grease to the connections. My mechanic did that, and it's supposed to help prevent future corrosion issues. Let me know how it goes when you get it sorted. Always good to keep track of these common issues for future reference!

Thanks everyone! Just wanted to update that I took my i3 to the shop today, and you were spot on! It was indeed a corroded wiring connection to the temperature sensor. The mechanic showed me the damaged wiring, and it looked pretty nasty with all the corrosion built up. They cleaned up the connections, replaced some wiring, and added that dielectric grease you mentioned. The whole job took about two hours and cost less than I expected. The temperature readings are now stable, and all the climate control functions are working perfectly again. Really grateful for all the advice here, it saved me from potentially more expensive diagnostic work, and I knew exactly what to tell the mechanic to look for. It's amazing how such a small issue can cause so many problems! Will definitely keep an eye on it during wet weather, but feeling pretty confident this has solved the problem. Thanks again for sharing your experiences, it made this whole repair process so much smoother!