Now adays mostly for sale Prius are with battery issues.
If you have changed the hybrid battery then you are good to go, if NOT and you bought the car in now adays like 2009-10-11 model.
Then brace your self for an error.
If the hybrid battery error came, only solution is to change the battery, if 4-5 cells are damaged, you can replace the cells but still some time the other cells cant pair with new cells and error came again after some time.
Now adays hybrid battery cost 1lak to 110 k.
When error came on screen iknow its like a mini heart attack to some owners (was for me) , then you dont listen to family what they are saying, you cant remember why you cane to grocery store, just one thing in mind, now what to do? Iknow its expensive battery and everyone cant afford it, but you have to do something.
For time solution you can remove the negative terminal of your 12v battery which is also in trunk of prius and beneath the rear seat of aqua for 2-3 mins. Plug in back and start and the error will be removed for some kms.
From obd scanner which is with electritions you can refresh the error for 200-600km (depending upon your current hybrid battery condition).
Coming from Ex Prius UK model owner