So I use my car as a "work truck" and part of my duties involves stopping at a number of houses(8-12) for 5-15 min at a time and then driving 2-6 miles to the next house. What is the "tipping point" of efficiency in time elapsed between leaving the car in ready mode and turning the car off? Travis
0-30 sec Anytime the car is in ready will use more then if it is turned off. The booting up the car from the 12V battery is a few seconds work for the 12V battery that nothing mechanical involved (not counting the relay movement). It is more convenience than anything else. All juice coming from the battery (HV) put in by the ice (OK you maybe going downhill sometimes). I think you are not asking the right question though.
That is correct !!! If car is in Ready and you walk away WITH the remote... the car remains drivable ... thief can not restart it if stopped (and turned off) but that is too late.
I appreciate the concern about the car being stolen but where I am parking my car it is not a significant concern. I have been doing this with my old car via leaving the key in the ignition for years. The "key" is in my pocket and I am aware that the car could be driven off by anyone. I was under the impression that the car had a mandatory "engine on when started" cycle even if the coolant is fully warmed up. Educate me please. Ironically it would be more convenient to turn the car off so it is not triple beeping every time I close a door or the hatch.
With an ICE, it's 60 seconds. That's why even non hybrids are coming out with Stop Start engines. For a Prius? You're looking at single digit seconds depending on your current draw. If you're concerned about about warm up time, you'll have the same problem whether you leave the car off or in Ready mode. No net loss either way. It's not mandatory at startup. It depends on temperature.
This is a very interesting question. I would think the big concern or questions is "how much gas" the car will use with using the 2 different methods. Some of the more technical people will confirm this, but the Gen 2 Prius the ICE would start up everything the car was restarted so it would use more gas (I think) than just leaving it on and the ICE would for the most part stay off. However, if I'm correct, the Gen 3 can be restarted without the ICE coming on (if it's warm enough), so my guess is it won't make much of a difference which procedure you use.
Yes, if the coolant temperature is over 65°C, the engine won't come on until you accelerate hard enough. At that time, it may stay on longer than normal, even if the coolant is in the 80s or above. Within maybe 2 minutes or so, it'll go back to normal warmed-up operation. To some extent, I think the answer to your question depends on more factors, like whether you're traveling at highway speeds; if so, then I would always turn off the car, since the engine has to run anyway. A 5 minute stop followed by 2 miles of low-speed city driving (especially if there's a lot of stoplights) is probably worth leaving the car on. A 15-minute stop followed by 6 miles of city driving is probably not worth leaving the car on. Personally, I'd suggest just turning it off. The only time I leave the car running is when I know I'm going to return in only a minute or two - and it almost always takes longer than I expect and ends up hurting my mileage.
In warm weather, if you're running the a/c, turn off the ICE or else you'll always be running with a low SOC and your mileage will suffer.
I should have notated that it is always with the radio off and the climate control off to minimize electrical draw. And normally it would be low speed surface street travel. I have noticed that when I turn off, then on the engine runs when it wouldn't normally compared to leaving it in ready and just driving off. Typically when I do this the battery display hasn't dropped even one bar. I realize that doesn't mean there is no current draw rather there seems to be minimal current draw. Travis
Just for fun I'd be interested to see the difference in your fuel mileage (if it's the exact same route your doing), doing it one way say for a week and then doing it the other way for the same period of time or actually the same mileage.
Unfortunately my "commute" is 18-140 miles daily depending on all kinds of factors. Only 18 of those miles are daily consistent.
