peter_hartmann1
BMW 8 Series Water Sensor Alert: Repair Tips & Costs
Check engine light on
Fault stored
Shaking while idling
4 comment(s)
Thanks for sharing your experience! Really helpful since it sounds exactly like what I'm dealing with. You mentioned they replaced both the harness and sensor, would you mind telling me roughly what you paid for the whole job? Also curious if you've had any other related issues pop up since getting it fixed? The wiring inspection tip is super useful, gonna make sure they check that properly.
Hey there! Happy to report back about my BMW repair costs. In my case, they actually didn't need to replace both parts, turned out just fixing the cable connection was enough, which saved me some money. The whole thing came to 95 € for the repair work, which mainly involved fixing the faulty connector and doing some testing to make sure everything was working right. I'm actually really glad you asked about follow-up issues because I can confidently say there haven't been any since the fix. The water sensor's been working perfectly, engine's running smooth, and that annoying check engine light hasn't come back. It's been such a relief to have it sorted properly. Honestly, having a mechanic who knew to check the wiring made all the difference. Some might've just swapped the sensor without looking deeper, which wouldn't have solved the real problem. If your situation's anything like mine was, definitely get them to look at those connections first, could save you from unnecessary parts replacement. Just keep in mind that even though this worked for my car, yours might need something different, but at least get them to check those connections first. Good luck with the repair!
Thanks a ton for the detailed info! Actually just got back from the mechanic today. You were spot on about the wiring, they found corrosion in the connector, plus a tiny crack that was letting moisture seep in. Definitely cheaper than I expected after hearing horror stories about BMW repairs. The mechanic showed me the damaged parts and explained everything. Total bill came to about 120 with labor since they had to replace a small section of the harness. Been driving it for a few hours now and what a difference! Engine's running smooth again, no more check engine light. Really glad I asked here first instead of jumping into replacing the whole sensor unit like the first shop suggested. Would've cost way more and probably wouldn't have fixed the actual problem. Sometimes these seemingly complicated issues have pretty straightforward solutions when you find the right mechanic. Thanks again for steering me in the right direction. Time to enjoy my properly running BMW again!
Had a similar issue with my BMW M5 (2015) last year. The symptoms matched exactly what you're describing, rough engine and CEL. Initially thought it was just a sensor, but turned out the wiring harness connecting to the coolant temperature sensor was corroded and had some damaged pins. The repair wasn't too complicated but definitely needed a proper diagnosis. The mechanic showed me the connector had moisture damage which caused intermittent signals. They replaced the harness and sensor, then recalibrated the system. While not a major repair, it's crucial to fix it promptly since incorrect temperature readings can affect engine performance and protection systems. The car's been running perfectly since the fix. Make sure whoever checks it tests the wiring, not just the sensor itself.