So .. funny thing happened to me on the app (v1.28). I walked away from the car and into a store w/ my wife. As she was "rounding the corner" and I knew we were going to leave I went to turn on the heat in the car (using my app). But, I couldn't control anything (incl. climate). As I kept trying to figure out why everything was greyed out (on the widget too), I noticed that the mode was in "Driving" (see photo). I panicked and ran out to the car not knowing what to expect. The car was fine (and in Park).
I restarted my iPhone and everything came back and worked as expected.
Moral to this story .. my iPhone needed a reboot .. nothing wrong w/ the car .. phew!
Now, thanks to
@bdham, I realized there was an update available, and I just updated the app to v1.29 (2173).