2010 prius won't start after running out of gas

Thought I'd give my opinion since I've been through some of this with my Prius. A few years after getting my car, I ran out of gas a couple miles from the gas station I was trying to get to. How I knew it was out of gas was that I couldn't go faster. It seemed I could only maintain current speed and when I slowed down, the battery wouldn't speed it back up. Eventually I had to pull off to the side and stop. A police officer helped get a gallon of gas to put in it, but it still wouldn't start. After calling roadside service, they put in 2 more gallons, which finally made it start. Hearing all the horror stories in here about burnt out fuel pumps and drained HV batteries, it sounds like I dodged a bullet and luckily I stopped it when I did.

Also, last year, my nine year old 12v battery died after not driving the car for almost a month. At first the engine started just fine, but after about 30 seconds, the engine stopped and everything started lighting up like a christmas tree on the dash. The engine would not start again after that. Operating the door locks sounded noticeably weaker so I knew it was the 12v battery. The HV battery had charge in it, and the 12v battery at least still had some voltage, enough to barely operate the locks and light up the dash. So I question the notion that the HV battery actually cranks the engine. If it did, my engine would have started. And sure enough, as soon as I replaced the 12v battery, the engine started right up! And the guy who says a Prius can't be jumped must not read manuals. It clearly states in the Prius manual how to jump the car, like any other car, to start the engine. Why would they put that in the manual if it was the HV battery cranking the engine?!?

 

The 12v battery powers the computers that tell the computer that all is well with
the computer and you can ready the hybrid system. If the 12v battery is low/weak, the
computers can't start correctly and the hybrid system will not be able to start.
Jumping with a good battery gives the computer what it needs to ready the hybrid system.

 

Pull the orange high voltage battery disconnect and try to start the engine from 12V with a new charged battery.
Post a video of you starting the engine. Ok?

 

Clearly you need both batteries. The power that cranks the engine itself comes from the traction battery, but all the power to make the car's computers want to crank the engine comes from the 12-volt battery.

Jumping a Prius, of course, works just fine if the reason it isn't starting is a low 12-volt battery.

On the other hand, if the 12-volt battery is ok but the traction battery is too discharged to crank the engine, there's no easy jump fix for that.

Pulling the orange disconnect will indeed prevent the car from starting, but that's 'cause it won't even try to crank. It will light the warning triangle and set a P0A0D code (hey dummy, the orange disconnect is pulled) and the car won't go READY or try to crank. If someone is really determined to "question the notion that the HV battery actually cranks the engine", they might still say that experiment hasn't convinced them.