What the difference between "车上“ and ”车里”

Here, the meaning of 车上 and 车里 both "in the car", but just different emphasis objects.

Noun + 上: emphasize the top or surface of an object
Noun + 里: emphasize the place

eg:
脸上 on the face
脸里 (NOK)

桌子上, on the table
桌子里, inside the table

房间上, on the room
房间里, in the room

“some nouns + 上” = “some nouns + 上”
eg： 心里/心上 嘴里/嘴上 手里/手上 亭子里/亭子上