Have had my 2012 Five since March- but mainly just drive to work (28mi) and a few times into NYC (50mi). Last week while on vacation we drove up to Lake George (250+ mi), Howe Caverns, etc... That was my first long trip in the Prius. Had two issues... 1) While stopped at a traffic light the "traction control" icon suddenly came on and stayed on- and I wasn't moving at all at the time- my foot was firmly on the brake. Tried to creep up a bit- but the car wouldn't move. I forgot the procedure to clear it- so being that the traffic signal was still red- I turned the car off then back on- that cleared the icon and I could move again. 2) In mid route the GPS froze up, tried turning it on/off through the apps button- no luck. It just showed a static map of somewhere in CA even though we were in upstate NY. Drove with it locked up for about 30 min. Luckily the other parties we were traveling with had SUV's and needed gas shortly after my GPS locked up- so while they were fueling at the gas station I switched the car off then on again and the GPS started functioning again. Glad I had my Garmin 1450LMT along for the trip as I don't like the Prius GPS Nav system to begin with.
The flashing traction control light was your hill start assist. It comes on when you step on the brake hard and will go off when you step on the gas. The nav I'm guessing was just a glitch.
1) You accidentally activated the Hill Holding Feature. Press the brake pedal very firmly for a few seconds and the TRAC light will start flashing. It will hold the brakes even with your foot off the brake pedal. 2) I am never impressed by the Prius' Nav. I use that screen to display the energy monitor.
No offense, but how do you know that for sure? It might be, but OP says he tried to move forward and the car wouldn't move.
I've practiced using the "hill start assist" and have always heard the "beep" it makes when it sets- didn't here the "beep" in this situation and I don't think I was stepping on the brake hard enough to engage the "hill start assist". That being said, we were just re-routed by the Garmin GPS (due to traffic delays near Albany) tensions were running high and we were doing a lot of communicating (in two different languages) with the other two cars in our group via walkie-talkie at the time an I may have missed the "beep". If it wasn't the "hill start assist" and it was the action traction control feature- does that immobilize the car? FWIW- I think the icon was solid on- not flashing. Also- I know by experience that the hill assist disengages it self after a few short seconds... this did not clear/disengage by itself.
Don't blame the Prius for your GPS problem. The real problem is that those people in CA think they're the center of the universe and seem to have convinced your Prius of that.