I've been having a weird issue this winter (my first with my 2008 G35x) with some of the electrical systems in my car.

When the temperature drops below about 5 - 10 degrees F (which it does quite often here in ND) the dials on the right side of the instrument panel, the speedometer and fuel gauge, stop working. The engine temp and tachometer work fine.

The fuel gauge sits at "E" and the speedo at 0 as I start driving. It doesn't matter how fast I'm going. Once the engine warms up a bit, the speedo will kick in once I come to a stop and the dial can "catch". Even if the engine is warm but I'm moving the dial won't kick in. The colder the temperature the longer it takes for the engine to heat up and, subsequently, the longer it takes for the dials to start working.

The fuel gauge will only give me a correct reading once I shut off the engine and restart it (after the engine is warm, of course). The approximate miles remaining on the video display is about accurate so I'm led to believe this is also just an issue with the instrument panel.

The only other symptom that seems to be associated with this cold weather phenomenon is that my headlights are on auto and the sensor doesn't seem to pick up the fact that it is, in fact, daylight out once I leave my garage. Sometimes it'll come to life midway through my morning commute and other times not. It does seem to be affected by the cold because it never happens if the weather is warmer and all of my dials are working. This is the same sensor that controls the internal light brightness so all my dials are dimmed as it assumes it's dark out.

I brought it into my dealer (250 miles away) but they said they couldn't troubleshoot it as it was 45 degrees that day and everything was working just peachy. There were no bulletins or anything from Infiniti that seemed to be related.

Any ideas on what the issue may be?

 

Sounds more like an electrical issue. I have yet to see such malfunctions and, I too, get those temperatures in upstate NY.

 

yep, sounds like an electrical issue.
it gets freakishly cold here in northern IL and i have yet (knock on washi) to have a problem that you are experiencing.
and of course the problems are not replicable and those are the problems that are hard to fix. when it starts getting super cold out again, do not hesitate to bring it into the dealership to have it looked at.

 

We've had quite a few below zero days this winter but I've never seen these symptoms.

 

we've had -20°C a couple of times & no issues like that.