My Prius 3 2016 is three year's old. When I fill up my tank it says 435 miles until I need to fill up my tank again. Do I have a bad battery?
That’s pretty normal for fuel range. The range is based on your consumption # times gallons of fuel remaining in the tank. Mine shows on average 416 to 480. I’m in SW Indiana, and the temps are running in the 30’s to 40’s. The warmup penalty is a pain in the asterisk.
it doesn't use reserve gallons in the equation, just capacity from full to blinking pip. you're better off to start measuring your fill ups and computing mpg's. keep a record for average, this will help you determine any future problems
Never mind that guestimated forecast, which is sandbagged by a significant safety margin. What MPG are you getting? That is what matters.