Plug-in on HV: running out of gas causes critical error

[2002]

To clarify (in my comment #15) some who ran their Prius cars dead after running out of gas would have to have their car towed to a Toyota dealer to get the battery pack resuscitated.
These cars lost the battery charge to crank the engine.

From what I remember reading the Prius Prime has an odd "feature" that if you run out of gas, just putting in one gallon won't work, you have to put in a couple of gallons or more. Probably some sensor that doesn't get triggered until you have put that much in. The workaround if you can only put in one gallon is to unplug the 12V battery negative terminal to reset the car.

 

[victor_2019]

As i said, when you run out of gas and EV range, the car can either continue running and damage the battery or shut down to protect the battery.

Then you reply "oh, there's no way to damage the battery, the car will shut down before that happens"

Yes... That's what i said?

And i still strongly disagree that it's not urgent to get off the highway in that situation.

If the system tells you the car will shut down in 20 miles, that doesn't mean you get an actual 20 miles. It could be 20, it could be 25 or 30, or it could just be 5 miles.

The estimated range is based on a historical average, not the real time driving conditions.

If you normally drive the car in the city at max 40 mph in stop and go traffic and eco mode and now you're on the highway doing 80 mph and it's cold out and you decide to turn the heating on, you'll be surprised how quickly the estimated EV range drops as you drive. You'll be lucky to travel half the estimate.

So if you see the car telling you to stop the car when it's safe, you better get of the highway at the next exit and look for a gas station instead of continuing on because the GOM is telling you that you have 20 miles left.

 

[2002]

As i said, when you run out of gas and EV range, the car can either continue running and damage the battery or shut down to protect the battery.

Then you reply "oh, there's no way to damage the battery, the car will shut down before that happens"

Yes... That's what i said?

And i still strongly disagree that it's not urgent to get off the highway in that situation.

If the system tells you the car will shut down in 20 miles, that doesn't mean you get an actual 20 miles. It could be 20, it could be 25 or 30, or it could just be 5 miles.

The estimated range is based on a historical average, not the real time driving conditions.

If you normally drive the car in the city at max 40 mph in stop and go traffic and eco mode and now you're on the highway doing 80 mph and it's cold out and you decide to turn the heating on, you'll be surprised how quickly the estimated EV range drops as you drive. You'll be lucky to travel half the estimate.

So if you see the car telling you to stop the car when it's safe, you better get of the highway at the next exit and look for a gas station instead of continuing on because the GOM is telling you that you have 20 miles left.

I think that is really the gist of it, the car doesn't know exactly when you will run out of gas or electricity it can only give estimates, estimates which hopefully get more accurate as you get closer but still neither you or the car know for sure.

Many of us in our younger days knew exactly how far our car would go after the needle reached empty because we had first hand experience . So we tended to shrug it off when the needle reached empty knowing that the car was good for several more miles.

You can do the same thing with Clarity and keep going past 0 HV range because we know (from other people's experience) that it will go several more miles. But I got burned with that once on my Prius. I had previously gone up to twenty miles past the low fuel warning with no problem, so I knew it would go at least that far. Then one time I got the low fuel warning and I didn't think much about it as I intended to get gas within about ten miles. Then a couple of miles from the gas station it ran out of gas, even though I had driven just eight miles after getting the low fuel warning. Fortunately it had enough battery to slowly drive the last two miles. So in that sense I was lucky although I'm not sure it was very good for the battery though.