Failed Heated Windows: Infiniti M Diesel Issue

Hey there! I had a similar issue with my 2008 Infiniti G Diesel (and I've also owned a FX). I have some experience working on cars, mainly basic maintenance stuff. In my case, it turned out to be a weak battery that wasn't providing enough power to the heating elements. My trusted mechanic diagnosed it, and after replacing the battery (cost me around 290€), everything worked perfectly again. Sometimes these electrical issues can be tricky to diagnose without proper testing. What's the mileage on your M? And have you noticed any other electrical issues lately (like slow starts or dimming lights)? This info would help me give you more specific advice. Best regards!

Thanks for your reply! My M has 14182 KM on the clock and I just had it serviced last month. Haven't noticed any battery-related issues like slow starts or dim lights, actually. Everything else seems to be working fine electrically, it's just those heated windows giving me grief. Maybe I should get the heating elements tested specifically? Would rather avoid replacing the battery if that's not the real problem.

Hey again! Thanks for the additional info about your M. You know, that's actually interesting because with such low mileage and a recent service, I'm starting to think it might not be the battery after all especially since you're not seeing any other electrical issues. My bad for jumping straight to the battery conclusion! When I think back to my G, I actually had another incident (different from the battery one I mentioned before) where the heated windows acted up, and it turned out to be a faulty relay. That was a much cheaper fix than the battery only about 50€ including labor. Given what you're describing, this might be more in line with your situation. Have you checked if your fuses are all good? That's an easy first step before hitting up the mechanic. There should be a specific fuse for the heated windows in your fuse box. I'd start there, honestly. If that checks out, then yeah, getting those heating elements tested would be your best bet. Let me know what you find I'm curious to see if it's similar to what I experienced with my G!

Thanks so much for the detailed follow-up! You're right checking the fuses does sound like a smarter first step before diving into more expensive solutions. I actually didn't even think about the relay being a potential culprit, but that makes a lot of sense and sounds way more budget-friendly than replacing the battery. I'll check the fuse box tomorrow morning and let you know what I find. If it's not that, I'll probably take it to my mechanic and specifically ask them to check the relay and heating elements. Really appreciate you sharing your experiences with both fixes definitely helps narrow down where to start looking! Thanks again for taking the time to help out!