Infiniti QX Electrical Gremlins: Battery or Sensor Issue?

Hey there! I had a somewhat similar issue with my 2006 Infiniti FX35 last year. The symptoms were exactly like yours flickering lights and sluggish starts. After playing around with it myself, I finally took it to my trusted mechanic who diagnosed a faulty battery sensor microprocessor. Cost me about 315€ to fix, but it's been running perfectly since. Before diving into solutions though, how old is your current battery? Have you noticed any other electrical quirks? Does it happen more when it's cold? I also had an M35 before this, and these Infinitis can be sensitive with their electrical systems. Let me know those details and I might be able to help more specifically!

Thanks for jumping in! My car's at 44304 KM and just had its service last month. The battery's only about 8 months old, which is what's making this extra frustrating. The flickering definitely gets worse in cold weather, and lately I've noticed my power windows are a bit slower than usual. Beginning to think you might be onto something with that battery sensor diagnosis seems like our symptoms match up pretty closely. Did your mechanic mention if this is a common issue with these models?

Hey again! Yeah, after seeing your additional details, I'm even more convinced it's similar to what I dealt with on my FX35. When you mentioned the power windows being slower, that really rings a bell mine did the exact same thing before I got it fixed. From my experience and what my mechanic told me, it's actually a fairly common issue with these Infiniti models from that era. The battery sensor microprocessor can start acting up even with a perfectly good battery (which explains why you're having issues with a relatively new one). In my case, I initially thought I could save some money by just cleaning the battery terminals and checking connections, but the problem persisted. The cold weather thing is also super familiar my lights would go crazy every time the temperature dropped below freezing. Quick tip from my experience: while you're waiting to get it fixed, try to avoid using multiple electrical components at once (like AC and radio together) as it can make the symptoms worse. Oh, and definitely get it checked soon I waited too long and ended up stranded once when the sensor completely failed. Let me know how it goes when you get it checked out! Curious to see if it's the same issue I had.

Thanks so much for the detailed response! That's super helpful, especially the tip about avoiding multiple electrical components I'll definitely keep that in mind until I can get it sorted. I've already called my mechanic and scheduled an appointment for next week. The fact that your FX35 had the exact same symptoms, especially with the cold weather and power windows, makes me feel better about heading in this direction. I'll definitely update you once I get the diagnosis. Really appreciate you taking the time to share your experience it's saved me a lot of guesswork! Fingers crossed it's just the battery sensor microprocessor and nothing more serious.