How to load hybrid battery to 100%

[Mike J.]

2 minutes ago, TonyHSD said:

This only happens in very specific circumstances and always on hot engine, let say after few hours of driving on motorway and taking off the exit long down hill braking and battery gets full then stopping at roundabout and engine kicks in and run at least 20-30 seconds with light load, all can be felt through the car. Then engine cuts off, and when you start to drive the ice kicks in immediately and runs at certain rpm as when the car is cold during warm up process but here is exactly opposite to cool down the gearbox and discharge the hybrid battery. Auris , Prius gen 3 , Prius plus all cars with hybrid synergy drive 1.8 engine from 2010-2018 

I never experienced that at all in my Yaris. With a hot engine, interior temp as requested and non-empty Battery, the ICE always turned off when car became stationary, if not before.

[TonyHSD]

1 minute ago, Mike J. said:

I never experienced that at all in my Yaris. With a hot engine, interior temp as requested and non-empty battery, the ICE always turned off when car became stationary, if not before.

Yaris has slightly different transmission but I don’t know how they do as I never had one, but I had many of the models above new, old, used, all behave the same way. But again the hybrid Battery needs to be full, not middle on the gauge, outside temperature actually doesn’t matter, now I remember I use to do some drive around during lockdown and few hard stops downhill to clean the rusty brakes and Battery got fully charged and the ice kicked in no didn’t let me drive in ev mode with message ev mode currently not available, every time I was doing that and outside was cold, January and February. It happens to me very often, where a I live now. 👍

[TonyHSD]

Anyone with Yaris (or any other hybrid) can try that to see if the car will do it like Prius and Auris.

Drive on motorway for half an hour, take of the motorway on a slip road preferably downhill, brake harder than usual so you can generate more electricity to fully charge your Battery 🔋 and see what happens next if you stop at the roundabout or a traffic lights. Perfect place is M25 clockwise J23 south mimms services 👍

[MikeSh]

5 hours ago, TonyHSD said:

every time I was doing that and outside was cold, January and February.

But that could be down to cabin heating needing the engine heat. You need to turn that off to get a more reliable evaluation.

[Mikw]

5 hours ago, TonyHSD said:

Anyone with Yaris (or any other hybrid) can try that to see if the car will do it like Prius and Auris.

Drive on motorway for half an hour, take of the motorway on a slip road preferably downhill, brake harder than usual so you can generate more electricity to fully charge your battery 🔋 and see what happens next if you stop at the roundabout or a traffic lights. Perfect place is M25 clockwise J23 south mimms services 👍

Yes, this works. I live near a dual carriageway and if you come off the power early, and brake late level of charge on the hybrid Battery indiacator goes up quickly.

[TonyHSD]

14 hours ago, MikeSh said:

But that could be down to cabin heating needing the engine heat. You need to turn that off to get a more reliable evaluation.

This make sense but in my cases it’s not relevant since the car been used long enough and cabin has had its set temperature reached.
 

There is another possibility why the car refuses to go into EV mode when Battery is full, might not be the full Battery itself or any eventual discharge process but the brakes servo booster that requires ice to run to create more vacuum and after long downhill and frequent use of the brakes the car servo needs more vacuum and the ice kicks in to deliver exactly that. I think this is it, because when I was experimenting during lockdown I did few hard stops in N so no regenerative braking and then select D and the ice kicked in exactly the same way as it does when Battery has been fully charged after long downhill braking.

Now we have one reason with two possible scenarios why the car with full battery refuses to go into EV mode: the reason is because the ice is running and here is possible scenarios or combination of them. 

1. Battery fully charged and ice is running to discharge?,! 

2. Servo booster needs vacuum and ice is running ?! 
 

Thank you for all your comments. 👍

 

 

[Mike J.]

14 minutes ago, TonyHSD said:

There is another possibility why the car refuses to go into EV mode when battery is full, might not be the full battery itself or any eventual discharge process but the brakes servo booster that requires ice to run to create more vacuum.

The Yaris Hybrid brake booster vacuum is created by an electric motor, same as the heater pump and the aircon compressor! You can hear the booster pump when you first open the driver's door.

[TonyHSD]

22 minutes ago, Mike J. said:

The Yaris Hybrid brake booster vacuum is created by an electric motor, same as the heater pump and the aircon compressor! You can hear the booster pump when you first open the driver's door.

You are right ! Just looked at it they are electronic on both axles. Well then it’s something to do with the Battery. 👍

[RickyC]

I think that there's another cause that keeps ICE running when Battery is full:  GPF cleanup.  

In Italy many Yaris IV users ( also my car is showing the issue ) are complaining about this strange behaviour.

It happens mainly to users that drive in towns with slow speed and frequent starts and stops.  Toyota Italy is aware of the issue and has collected many data installing special data capture HW in the car of some volunteers owners.

Currently there's still no feedback from Toyota.  The issue was more accentuated during cold months but still happens also now with a sunny and warm climate.  

The issue happens also on other Toyota Hybrid cars ( CHR, RAV and  Corolla ) even if less frequently due to a more extra urban use of this cars. 

The strange thing is that currently there are no evidence of this issue outside Italy.  That's i really strange because the engine and the anti pollution components are the same on all European production and I expect that the cooler climate of Northern Europe should enhance the probability of this behavior.