Air vents in rear seat

[Chicagobob]

I do not feel any (warm) air coming out of the small B-pillar vents in the rear seat. Is there something I must activate to get an air flow?

 

[joegr]

I think that the air for those travels though the front doors, so those have to be closed when you are checking for it. Otherwise, there possibly is some climate control setting from the entertainment screen that turns those on and off.

 

[iSOBigD]

Like Joe said, the air goes through the front doors. There is also there's a switch to open/close the vents like in this photo below, as well as rear seat HVAC controls in the center arm rest if you have the Ultimate model.

 

[Goaterguy]

2018 G90 has a recall on the coolant tube feeding the transmission. One of the symptoms of coolant loss is the lack of cabin heating. Not enough coolant goes through the heater core to heat the cabin. Check your coolant level if you haven't had the recall done.