Droid13 — I knew you'd like those!

H2O Doctor — I think that most of the discrepancies you (and others) have found are likely due to consistent under- or over-filling of the fuel tank beyond its 65-liter nominal capacity. (Just how you can tell when you're actually at its nominal capacity is a nice question!)

By the way, I think that Toyota have designed the "cruising range" display so that it aims to reach zero when the fuel gauge reaches E(mpty). This seems eminently sensible to me. Once it reaches zero it won't go positive again, even if your FE rises dramatically during the "reserve" portion of the tank. It also seems to learn your driving habits, so that after a few tanks, its estimate of the remaining cruising range gets better, all else being equal.

Stan