Stopping HV charging from low SOC at idle

Is your heater on?

 

How many bars on your SOC are you considering 60%.

Although heater is off what temp is the climate set at when you turn it back on?

 

I misread your original post and was thinking you were in park.

Is this what you are experiencing while driving?

 

That doesn't sound normal to me. On my 2005 Prius the engine will only continue to run at idle if

1. The ICE is very cold.
2. It's required for the cabin heat setting.
3. The SOC is really low (pink bars). Mine cuts the engine as soon as it reaches 2 or 3 bars.

I don't see how that's better, idle just wastes energy.

 

Slimothy,

What is Torque showing the SOC to be in % when the MFD shows 6 full blue bars?

AND

What is the MFD showing when Torque reads 60% SOC?

 

For all the effort you are going to, it seems to me that all you need to do is shift to "B" mode when doing the long downhill and coming to a stop as you describe.

Have you tried using B mode and seeing what the difference is?

 

have you tried powering down and back up again?

 

FWIW, normally unless there is a BIG load on the traction battery, the ICE should kick off somewhere around 3 to 4 blue bars which is supposed to be ~40% SOC. If Torque is saying you are going up to 60% and the MFD is showing 6 bars before the ICE kicks off, something is amiss.

What uart said above is what I see also.

If I have the A/C running (heavier load) sometimes the ICE will run until 4 bars, but for the most part usually kicks off around 3 bars and doesn't kick back in until 2 bars which would be pink.

Anyway, to make a long story short I would simply utilize B mode on the long down hill runs and let the Prius take care of itself. It is real hard to outthink or outsmart it.

Have fun and best of luck to you.

Also, I forgot my manners earlier. "Welcome" to Prius Chat!

 

Ahh, now we are getting down to where the rubber meets the road. The old S4 stage. YES, the Prius operates completely different in the way the ICE runs when you go through the different stages. And I CAN understand why the SOC would continue to rise on up to 60% if you are NOT in stage 4. That is NORMAL.

I do know for a fact that the SOC will rise to 60% if you are not in Stage 4. I see this anytime I allow the Prius to sit and idle on a cold morning. Yes, I know it wastes gas. But I am old and arthritic and I don't like driving a cold car. I am stiff enough as it is.

With all that has been said, I think you have NO problems.

 

Ok this is getting interesting. I'm certain than mine cuts out at about 3 bars in every stage except stage1 (the first stage when the ice is still cold). I wonder if this is a year model difference or a aircon heater setting or something. I'm absolutely certain that I've never seen mine charge to 6 bars without accelerator input.

 

uart,

I don't have a ScanGageII so I can't monitor exact temperature to determine actual stage. The way I tell if it is in stage 4 is the slow 10 second shut down at a stop sign or traffic light after going through the warm up cycle and then after that being able to glide down to 10 MPH while showing 99.9 on the MFD.

In reference to the SOC charging @ 6 bars, I have seen the arrows going from the ICE to the traction battery on the MFD when the Prius was sitting idling in the drive way after powering up on a cold morning. It would continue to charge for some time and then stop, then you would see the arrows point again to the traction battery signifying the charge while still @ 6 bars. I emphasize that this is only seen when warming up the Prius in VERY cold conditions (ambient 30 F ~) However once the Prius warms up enough the ICE will shut down and then after that the charging will begin at 2 bars and kick off at 3 or 4 like normal.

I really need to get a ScanGage.

 

Ok that sounds more like what I'm familiar with. I often warm up for about a minute in the morning and it will definitely charge the battery, even 6 or 7 bars, during that warm up.

What I'm unsure about is the idea (as suggested by the op) that the ICE will *continue* to run and charge the battery all the way from 2 bars to 6 bars, even if the ICE has sufficient temperature to cut out. This is the thing I've never seen.

Yeah but it would seem strange that a requirement for your stricter emissions standards would be to allow the ICE to idle unnecessarily.

Can we get some confirmation from other US owners here. Under what conditions will the Prius ICE remain on and idling, with no accelerator pedal input, no heater requirements, and engine coolant at a reasonable temperature (150 to 160F). It doesn't seem right, has anyone else seen it?