In cold temps, ICE turns on at the begining of a trip when I have plenty EV. Why?

My experience has been that if you've never got up too much speed, a short bit of downhill isn't a problem, but I don't have as long a downhill as that. Depends a lot on how steep it is, but if you can get away with crawling out and then letting the hill do your acceleration you'll probably be fine. You'll need to learn the technique of having your foot on the throttle just enough to kill the automatic regen, without significantly sending power to the engine.

 

I too live at the top of a hill. I have to shift to neutral after charging to avoid firing the ICE. Seems to be no problem shifting back to D.

 

both of the above are correct, but if it's too cold, or the hill is too long/steep, neutral is more reliable and does no harm to the mechanicals. if you have to go right back up after you hit bottom, you have to be careful. i have this situation, and if there is a car on my tail, trying to get up to the speed limit too agressively (40 mph) can start the ice at low temps.

 

The Prius (plug-in or standard) does not have a transmission. It has a Power Split Device that distributes power between the gasoline engine, a motor-generator, and the wheels (to which another motor-generator is attached), and doesn't involves engaging or changing of gears. Its mechanical design requires that the gasoline engine be spinning (albeit maybe at low power) if the car's speed is above about 62mph. Being in N prevents the gasoline engine from kicking in, so there is a risk of damaging the system by "over-revving it" it if you go too fast in N.

 

Rather extreme, wouldn't you say?

 

Let's see, after the snow storm last night, I hit the button so I could move the PiP out of the driveway to finish clearing the snow. The readout said 18F and the ICE started, now what did I miss? Even though everything was off, I had the defrost/heat icon on the HVAC display, so I figure that did it. Later in the evening, I had to do some running around. Readout said 12F, hit the button and ran around strictly in EV.

This morning it was 7F, when I hit the button and the ICE came right on. When I got to work, I plugged it in to charge. 4 hours after the car was all charged up, I moved it into the Sun to melt the rest of the snow off. The readout had 21F before I moved and the ICE didn't come on.

 

somethings not right, mine never comes on if the temp is low and the fan is off.

 

Have you tried it with the defrost/heat icon showing?

 

are you talking about defrost/feet? if so, i keep it there all the time in winter so i can hit the fan and fresh air to clear the windshield.

 

Yep, that's the only difference I had when hitting the button at 18F and at 12F.

 

you got me.

 

The temperature on the dash is not necessarily the battery temperature, you found that out by driving and the temperature went to 12 degrees. 14 degrees is the threshold when ICE kicks in or not

SGH-M919 ?

 

ICE started at the outside temp of 18F and didn't at 12F and the car is outside all the time.

 

you know, the car sitting outside all the time probably has something to do with it. mie never does, except when i go somewhere, and then, the batteries have already been warmed up. i guess this conversation should involve people who keep thier pip outside in cold climates.

 

When I hit the button to leave work, I cycled the air outlet button to the defrost/feet mode to see if the ICE would start and it didn't.

 

the enigma machine.

 

Agreed my car is always outside so the dash temperature is a little misleading because we don't really know where the thermometer is

SGH-M919 ?

 

Should be just behind the front grill.

 

So.....it's not located on the battery, which would've been nice if it was, so we can accurately determine when that 14 degree threshold is near.

 

The 12V battery has a sensor that sits over the top of it, but I think it's there to make sure the battery doesn't overheat.