get this, '19 jeep
My '15 Renegade doesn't do the horn/light thing that I know of.
However, when the humidity dropped around the first of October, the tire pressures all dropped the next morning, from 35 to 29.
Just last week we got a cold spell (30's in the morning) and they dropped again, from 34 to 29/30) all in the same day.
Next time I will try it without a gauge.
Was the ignition on?