why doesn't air blow thru the passenger side center vent on my bmw x5, f15? ?

Usually it's a problem with the blower motor, which usually has a repair cost bad enough to cause a surprise bowel movement.... if you're lucky it's just the resistor, which isn't as awkward to get at.

Think i've seen a few other possible causes on some of the popular car repair channels on YouTube that I watch as often as I can..... computers on modern cars can cause a few weird issues as well that can stump a lot of experienced mechanics.

https://www.youtube.com/watch?v=0hc5BMEJDAI

https://www.youtube.com/watch?v=zm1HRU64Dpo

https://www.youtube.com/watch?v=Q-i0tytSYIM

Check for a bad blend door actuator.

maybe you should get a mechanic to check it out

maybe you should get a mechanic to check it out