Unfortunately unlike the bus we don't get the little chirp when the mode changes. I found that useful a few times going in to LAS about 8 yrs ago when brand yellow was having trouble with the nav database and arrivals wouldn't connect up with the approaches properly, so you'd get a vnav disconnect at some point during the arrival or approach. Chirp chirp WTF is it doing NOW? is way better than whoop whoop terrain terrain pull up pull up (also brand yellow into vegas about 8 yrs ago).