Lancer's Mysterious Electrical Chaos, Help Needed!

Hey there, I had very similar issues with my 2019 Mitsubishi Lancer (gas engine) last year. The symptoms you're describing sound exactly like what I experienced, nav system shutdowns, unusual warning lights, and erratic speedometer behavior. Turned out it wasn't actually the Flex-Ray bus in my case. The main problem was corroded cable connections at the main wiring harness near the firewall, plus a loose ground connection. My trusted mechanic found multiple spots where moisture had gotten in and caused connection problems. The fix involved cleaning all the connections, replacing some damaged connectors, and securing the ground points properly. It wasn't a major repair in terms of components, but it did require careful diagnostic work to pinpoint the exact locations of the bad connections. Since the repair, I haven't had a single electrical issue. I'd definitely recommend having someone check the main harness connections and ground points before assuming it's a more complex bus problem. Hope this helps with your troubleshooting!

Thanks so much for sharing your experience! That's really helpful to know it might just be corroded connections rather than something more serious. Do you remember roughly how much you ended up paying for the diagnosis and repair? And has everything stayed working properly since then, or have you noticed any other electrical quirks pop up?

Hey again! Happy to give you an update! After seeing my mechanic about those electrical issues I mentioned earlier, everything has been running perfectly in my Lancer. The final diagnosis actually showed it was indeed a Flex-Ray bus error, specifically a faulty cable connection that needed fixing. The total bill came to 155€, which honestly wasn't as bad as I was expecting for an electrical repair. Since getting it fixed (it's been about 8 months now), I haven't had a single problem, no more nav system shutdowns, no weird warning lights, and the speedometer is working exactly as it should. It's such a relief not having to worry about those unusual electrical gremlins anymore! Sometimes these electrical issues can seem really scary and complex, but often it's just down to something relatively simple like a bad connection. I got lucky with my mechanic, he knew exactly what he was looking for and fixed it right the first time. Let me know if you need anything else, always happy to help out a fellow Mitsubishi owner!

Thanks again for all the details! I actually just got back from the mechanic today and wanted to give you guys an update. Took your advice and had them check the connections first. Turns out I had a similar issue, some corroded wiring connections and a loose ground wire were causing all the trouble. The mechanic found water damage near the firewall that was messing with the electrical system. Total repair came to $180, which included cleaning all the connections, replacing a few damaged wires, and fixing the ground connection. Way better than what I was expecting to pay! Been driving it for a few hours now and everything's working perfectly, nav system's back up, no more warning lights, and the speedometer's steady as a rock. Really glad I asked here before assuming the worst. Sometimes it's the simple fixes that do the trick! Thanks everyone for the help, definitely saved me from getting overcharged for unnecessary repairs.