if the fuel door, for whatever reason, fails to open, is there a way to get to it from the inside? if not how would you do it without messing up the door or paint? I had a 2002 Golf and you could access the fuel door/cable from inside the hatch by pulling off a panel.
Never thought about it, but if I couldn't open it with the lever inside the car while trying to fill up, I'd just try and use the key in between the fuel filler door and the body and see if it popped enough with a little leverage to open it with my hand the rest of the way. I had a rental once do this and a little pry of the key worked and it did not mess the paint up......
I know on the 2nd gen Prius if the fuel cap string gets caught between the tang and what it's supposed to contact, the fuel door may not open. In that case, you hold the release lever up while someone else puts something soft like paradox says, a credit card to open it. Then make sure the string doesn't get caught under the tang. I believe the 3rd gen design is not subject to that problem though. Don't pry on the door though, it will bend. If doesn't open, take it to Toyota.