Mine is exactly the same, usually predicts (fairly accurately, 16/17 miles), I have a stretch on Interstate to get to my office, which kills it, plus I'm usually using climate control in the "auto" setting. I think its working as intended, I'll try a back roads/climate off commute this morning and see if I can stretch it a bit. I think both plugs 120/240 do the same thing (supply AC to the car and the car then charges battery), once car tells the plug controller its full, it'll stop supplying, The level 2 only gets this job done more quickly.