[e2helper]

They all display the outside ambient temperature in radio display (if you select that display mode) but more likely you were looking at the display in AC control head which is setting for the INSIDE temperature for automatic climate control, not the outside temp

Auto climate control is standard on GTP and not avaiable on other models.

 

[e2helper]

Ahhh,

To cycle thru available display settings on radio keep tapping on the the DISP button on radio. When you see the display you want as your default press and hold until you hear a "BEEP". This becomes your new default display. Likely the 2 vehicles you looked at were set to different displays because you CAN set up air temperature to be displayed even when in XM mode.