This issue is 5+ years old. It started with a rare event of the nav screen (upper screen) that would intermittently drop out. It started with the occasional flash, like the iphone cable was loose. So I replaced the cable many many times, thinking that fixed it. However, the issue would come and go - sometimes going for many weeks before acting up again. It wasn't the iphone cable as it also occured without a phone connected (e.g. when trying to back up, access setup, etc.).

While under warranty I had the dealer look at it. It took a long time to reproduce, but they eventually saw it and replaced the head unit. Problem seemed to have gone away. Except a year later same thing. It gradually got worse and worse with more drops for longer periods. It has gotten to the point the nav screen doesn't come on at all, not even for backup cam. It is out of warranty now and would be crazy expensive to fix.

Observations:

• When the screen went dark it didn't actually go completely dark. The backlight still worked. It was as if what was being displayed was just a black screen.
• During glitching, sometimes a flash of static, or horizontal lines would appear.
• At first it seemed seasonal - perhaps related to temperature? But never got enough data to prove that

This definately looks like a physical/electrical, rather than a software, issue. Given the fact the backlight is working, and that the visual artifacts when glitching look to be digital in nature, my main suspicion is a loose data cable between the head unit and the nav screen. I have no idea if a data cable exists that could come loose in this fashion. But, this is what it appears to be. Second on my list is a failing processor / transceiver chip or circuit on either end.

Any ideas on where to start? I think I can get to the nav screen easily. But I don't know what's back there, and if there is a loose connection, how deep would that cable and connectors be? Pulling the head unit looks like a royal pain.

Without a working nav display I suspect the car would be difficult to sell or have very low value due to the cost to fix. So I'm feeling like I'm stuck with this. I love the car. But the lack of a nav screen makes it difficult / dangerous even (no back up cam, no setup menus, no carplay, etc.).

 

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Just curious, does the old dealer warranty repair invoice have the part number(s) for the '...head unit...' component they replaced?