EV city mode modificaton

To be completely clear about all of this:

Euro-miles are shorter than UK miles and US gallons are smaller than UK gallons.

Trust that's now completely clear

...but yes, it's rather a mish-mash. In the UK beer is still served in pints, fuel's in litres, food in grammes, but a foot-long hot dog is still just that. We drive at a certain mph over the speed limit, still talk about acres of land, horse races still enter the final furlong and I have no idea how to fathom the depth of a particular body of water - and we wonder why our kids can no longer add up?!

 

To pick this up again, I do seem to be getting what you call EV boost, if I've understood it correctly. I normally start my drive to work with both the EV and EV City green icon lights showing on the display (having turned the latter on). As previously said, EV City means you are nippier from 0 to about mid 30s, but a bit sluggish after that, however you just can't force the ICE on at under 54 mph or so because the throttle won't go into PWR even pushed to the floor (so you do need the right conditions for it).

Once I get up past mid-50 mph there's a beep and a warning that I'm too fast for City, which turns off, but I still have the EV light on. The arrow schematic then shows a combination of ICE and electric power. Sometimes the battery is boosting the ICE power, sometimes it is recovering some of it (or regenerating as I slow), and I'm often left with much the same EV range when I get down to EV speeds again ten miles later, but other times it can use up some of the EV mileage.

Just to be clear on the buttons, on the UK model they go ECO, EV-HV, EV City.

 

Interesting you say that - I can't get mine to do this!:

Yes there's small amount of range up/down as you state, but not the progressive battery usage illustrated here.

 

Ah, OK, IC. No, agreed, it doesn't do that. Maybe linked to the way we only get EV up to 52mph or so? Has there ever been any explanation of why the cars are set up differently for the different markets? Something to do with the government incentives, maybe?

 

I think that EV-City prevents the "progressive battery usage" to reserve EV miles for driving in the city later.

Also, I hypothesized that if you turn off EV-City Mode and were in plain old EV Mode that you would get "progressive battery usage". Anyone try that and can confirm or refute?

From Mobility Choice

I don't know why the US has a PWR Mode instead, though. I'd prefer EV-City Mode over PWR Mode, except that I would want "progressive battery usage" and EV up to 62mph.

 

EV-City cancels out at an indicated 58mph - exactly the same as normal EV mode. It (the icon) disappears from the instrument panel and can only be reactivated by a button press at a lower speed (unlike EV, which kicks in automatically once speed drops unless you actively switch to HV mode).

So no, it don't think it has any effect per se, since it's not active in any way once over the speed threshold BUT I am interested in the first part of your post - that is, it might be programmed such as to avoid inadvertent battery usage at higher speeds in order to retain EV-City capability. There might be something in that, perhaps.

 

Hm, that's not how EV Mode behaves, at least here. Going above 62mph does not exit EV Mode, even though the engine turns on. Of course, the EV icon goes away while the engine is on, but that's independent of EV Mode.
Can you toggle the EV Mode light back on when you are above 58mph by hitting the HV/EV button? If you see the EV Mode icon disappear above 58mph, that really sounds like it's automatically switches to HV Mode aboe 58mph, which would be consistent with no "progressive battery usage". I suppose it's possible they disabled EV Mode above 58mph, but I'm wondering if Toyota implemented the former rather than the latter.

 

Apparently the European and North American models differ in this area. Our European colleagues have reported that above their EV limit (58mph?) that they are in pure HV mode, whereas here, above our EV limit (~62mph) we are in so-called "EV-Boost" mode, where the ICE is running but providing minimal power and the battery providing most of the power. The green EV mode light is still lit, and the display has an outline of a car rather than the filled-in one that it has in pure EV mode. Switch to HV mode, and there are the two icons on the display, with a smaller car icon that is filled in if the ICE is currently off.

 

No EV works that way on the UK cars too, I think BB just meant that if you are in EV it kicks over automatically to just electric power once you drop below about 58. But EV City beeps, warns you with a message, and switches off over 58 and stays off until you re-engage it by pressing the button.

Because EV/HV works the same way, I can't see the benefit in preserving battery in EV so it can be used in City - we could do that ourselves by switching to HV.

 

Sorry, I was replying to ryogajyc. The EV light doesn't disappear when I go above 58, only the EC City if I had that selected. But we don't seem to get Boost in the same way you do as shown by that video clip.

 

Indeed, that's exactly what I meant. Seems odd that there does appear to be this difference in operation.

 

I've been watching what happens as I come out of EV City more closely the past couple of days. I'm coming to the conclusion that there isn't really any use of EV mileage at all, because when I think I am getting some, it's all in the first few minutes after EV City has kicked out. I suspect that is just the system recalibrating how I've used the EV, and because I've just used proportionately more to get up to 58 nominal it now thinks I can't get as far on what remains. So I think I agree with BB that there is no EV Boost at all, other than the normal combination you get in HV (using the HV part of the traction battery, is that right?).

 

When switching out of EV mode, the first minute is at low RPM to allow the engine warm-up gracefully. That's achieved by drawing more electricity that usual while in HV mode, hence the "EV-BOOST" name.

Whether or not you also have that while cruising at faster speeds is a different matter, but very easy to verify. If RPM of the engine stays unusually low and MPG stays unusually high compared to HV performance after depletion, that's it.

 

WRT your Para 2, no we in Europe (he says grandly - Europe will correct me if I misspeak, I'm sure ) don't see the types of extremely high mpg illustrated in the video I linked above; nor does EV range "tick down" after ICE warm up, hence we are assuming that in some way US and Euro PiPs operate differently in this respect.

...but we haven't the foggiest idea how to validate this suspicion!

 

Ah, thanks, so that's the explanation of why I lose the 3/10ths of a mile or so.

However, I've now got another possible difference to add to the US v UK/EU setup. From what others say here, apart from that loss on engine start-up you don't expect to lose more EV range if you have switched to HV, yes? But as far as I can see, the only difference HV makes to me is that I switch back to electric traction at a lower speed than if I was in EV.

With EV selected, the EV lamp is lit all the time, but the EV indicator in my HUD only comes on if I drop below 53 mph (I tend to be looking at this rather than the HSI). If I have HV on, so no EV lamp showing, EXACTLY THE SAME THING HAPPENS but only if I drop below about 45mph. Don't know if Bonefish Blues has the same experience? Or have I just misunderstood what happens in the US cars? I have crosschecked the manuals, incidentally, and can't see any differences.

 

The EV indicator behavior you describe matches US behavior as well. However, as mentioned earlier, even with the EV indicator off, high-speed EV mode in the US results in battery assistance to the engine and high mpg (100+) at highway speeds.