So I discovered a flat rear driver's side tire last night. Fixing the flat wasn't a difficult DIY project but this warning light on instrument remains ON and won't go away. Tire pressure is 34 psi on all four corners but that repaired tire is still marked red and 'FLAT TIRE - VISIT DEALER' sign is on along with orange triangular warning indicator on top center. Of course I've driven it after the repair, over 30 miles at speeds of up to 75mph.

Owner's manual states; A “Flat-Tire – Visit dealer" warning also appears in the vehicle information display. The chime will only sound at the first indication of a flat tire and the warning light will illuminate continuously. When the flat tire warning is activated, have the system reset and the tire checked and replaced if necessary. It is recommended that you visit an INFINITI retailer for this service. Even if the tire is inflated to the specified COLD tire pressure, the warning light will continue to illuminate until the system is reset. It is recommended that you visit an INFINITI retailer for this service. [8-32 Do-it-yourself]

Really?? You can't fix a simple flat tire on these vehicles? Does anyone know how to reset or clear this warning light?

You could try borrowing an OBD II Scanner at Autozone and try to clear it. One person online said that's what they did, but someone else said they couldn't see an error code and were not able to clear it. Not all scanners are created equal, so the latter may have been a cheap one that lacked some functionality. Anyway another person posted that theirs cleared up after two weeks of regular driving.

Thanks, I do have an old scanner somewhere. I'll give it a shot.
A flat tire shouldn't require a visit to a dealership IMO.

Update: I made a quick stop at a local Infiniti dealer and I was told by their in-house tech that Infiniti can only reset or clear the warning after I replace my run flat tire. What? I understand this is their some kind of safety protocol but really? Every time I get a flat tire, I need to spent $400 and have it replaced with a new one?

Update: It's been 45 days since my flat tire warning and it didn't go away. I went to my local Infiniti dealer today (same one as last time) and asked them to fix it. It took them less than 5 min and warning sign is gone now.