Icon meaning in car status (tire pressure)

[greentee]

Does anyone know what this icon next to the rear right tire means?
I got tire pressure warnings before but this one is new to me.

 

[Patrick W]

I think it means the charge port is open.

 

[greentee]

Oh oh that's right?
In any case, the tire pressure warning was on after I parked my car outside for a few hours.
It's been a nagging problem ever since I had the tire replaced after having a nail in it - sometimes showing a warning saying that it's 2-3psi lower than other tires. But a manually check showed that they're at about the same pressure. Even resetting the sensors didn't help.