I also experienced the on again / off again yellow Car on Lift icon, and noticed it came on after the car had been sitting for at least a few hours, but not after restarting the car after being off for just a short time. So I was already thinking battery.
Turns out the car was throwing multiple low voltage faults, and the battery was replaced. Also, I had a communication error with the VTG, so the VTG was replaced as well. Not sure whether this was related to the low voltage faults or not.
One week since the repairs, and have not had the yellow Car on Lift icon come back on since.