Weird behaviour from hybrid ecu

[King Crimson]

So last night me and a friend of mine were sitting in my car with the car in the ready mode, after sitting for a bit the engine came in as to fill the Battery a bit since it was nearing empty. After a minute or so the engine went from about 1500 rpm's to 1000, the noise levels were reduced quite a bit and the animation on the screen showed that the Battery was no longer being charged. The engine was still on for 2 more minutes, i got really confused as to why the engine was still on doing nothing instead of the Battery taking over and switching the engine off. Has anyone experienced this before? Did the ecu not know what to do at that point? 

Note that i had already been driving around before coming to a stop so the battery was already warmed up.

[AndrueC]

I wonder if it's for the same reason that the engine sometimes runs at 1,000 rpm prior to switching off for EV mode?

[Louie]

Hi Guys 

I have been getting this from the moment i picked up my vehicle from the dealer in January this year.. You are sitting quietly minding your own business when the engine chimes in normally this only happens if you are listening to your itunes or car radio with the power on( the vehicle announcing its not in go mode)   having previously switched it off. . My car still does strange stuff which i am currently ignoring just as an example i pulled up to some traffic lights recently and engaged the p button to park not the the gearstick. The car after about 15 secs suddenly lurched forward having decided to disconnect from parking mode and i had to employ my 72 year old reflexes to prevent a rear end shunt. Nothing surprises me today as i had a Golf 2l TDI that had a problem with its GTD box so when you selected reverse the AI in the gearbox would decide to lurch forward and then decide that was wrong and go backwards. I just had to remember in future to give any vehicles parked in front plenty of space.

My Corolla also puts the front mirrors into park automatically when you exit the vehicle but wont self lock using the fob weird or what its  like the design engineers forgot something after their Friday meetings at HQ. The locking procedure is totally random when using the fob sometimes it will lock other times i have to go back to the vehicle and press the on/off button while cursing profusely and no i have not left a door unlocked or window down !😫😩

[Timmon]

4 hours ago, King Crimson said:

So last night me and a friend of mine were sitting in my car with the car in the ready mode, after sitting for a bit the engine came in as to fill the battery a bit since it was nearing empty. After a minute or so the engine went from about 1500 rpm's to 1000, the noise levels were reduced quite a bit and the animation on the screen showed that the battery was no longer being charged. The engine was still on for 2 more minutes, i got really confused as to why the engine was still on doing nothing instead of the battery taking over and switching the engine off. Has anyone experienced this before? Did the ecu not know what to do at that point? 

Note that i had already been driving around before coming to a stop so the battery was already warmed up.

Yes, it happens all the time.There have been a few answers on this site, which include warming up the cooling system so the heater is ready if required, something to do with preparing the brakes (pressurising the hydraulic system, as with a non hybrid, the power brakes don't work unless the engine is running, not so with a Hybrid) , and other things I can't remember now.

So the ICE does run when it is not charging the Battery or powering the wheels. Basically, the Corolla is more computer than car. It is a shame Toyota don't issue a tutorial on how it works, for those interested owners who take in all the little quirks these Hybrids have. We just have to share information, and speculate on what is happening, much of the time! Unless a technician sees our query on this site  and answers.

[m4rkw]

Does it not say anything in the owners manual about how it's supposed to work? 

[AndrueC]

32 minutes ago, m4rkw said:

Does it not say anything in the owners manual about how it's supposed to work? 

Nothing specific. I don't even think it even tells you how to trigger EV mode by lifting off the accelerator pedal. If we ever do find an expert I'd also like a detailed explanation of why the blue acceleration guidance line does what it does. Sometimes pulling away it will suggest full ICE acceleration. Other times it wants you to barely tickle the accelerator at first then gradually increase the pressure.

[King Crimson]

3 hours ago, AndrueC said:

I wonder if it's for the same reason that the engine sometimes runs at 1,000 rpm prior to switching off for EV mode?

I think the ecu decides that the engine has done it's job in generating the necessary electricity for the Battery and then a second or so later decides that the vehicle is going at a speed that the Battery can keep up and turns the engine off. I'm guessing the ecu needs a second or so to make the appopriate calculations in order to make a decision.

[AndrueC]

Just now, King Crimson said:

I think the ecu decides that the engine has done it's job in generating the necessary electricity for the battery and then a second or so later decides that the vehicle is going at a speed that the battery can keep up and turns the engine off. I'm guessing the ecu needs a second or so to make the appopriate calculations in order to make a decision.

Oh but it can run the engine for several seconds sometimes.

[m4rkw]

8 hours ago, AndrueC said:

Oh but it can run the engine for several seconds sometimes.

Several seconds isn't very long. Maybe it's running it up to temperature in order to boil off any moisture in the crankcase to avoid the oil getting sludged up.

[TonyHSD]

Hi , there is nothing weird about behaviour of your cars, that is absolutely normal work of the hybrid system and ecu knows what it’s doing for sure😉 Sometimes may look and feel strange but ice needs to work to maintain temperature and to be ready to start and propel the car at any one moment. In some cases ice works as energy consumer to maintain the charge levels of the traction Battery too. There are many more interesting things that will make you wonder why is that through your ownership and this is part of the overall experience. For anything that it’s new to you you may look into Prius forums as basically your cars are exactly the same as Prius gen 4 under the skin. 👍

[King Crimson]

35 minutes ago, TonyHSD said:

Hi , there is nothing weird about behaviour of your cars, that is absolutely normal work of the hybrid system and ecu knows what it’s doing for sure😉 Sometimes may look and feel strange but ice needs to work to maintain temperature and to be ready to start and propel the car at any one moment. In some cases ice works as energy consumer to maintain the charge levels of the traction battery too. There are many more interesting things that will make you wonder why is that through your ownership and this is part of the overall experience. For anything that it’s new to you you may look into Prius forums as basically your cars are exactly the same as Prius gen 4 under the skin. 👍

To be honest i thought i knew quite a bit about the hybrid system or at least me, as a driver, i'd say im quite attuned with the car, for example i can tell when the engine can kick in or i could feel the power threshold of the batteries and that if press the gas pedal even a little bit the engine would kick in. Even though as many have said the system is totally seamless in speed i can still tell when the engine comes in without looking at the rpm's.  But there still seems to be a lot that we don't know and don't undestand, this hybrid system of course is extremely complex and even if an engineer that has worked on this system came in he would need a to write a whole book in order to explain everything.

[Catlover]

20 hours ago, Louie said:

Hi Guys 

I have been getting this from the moment i picked up my vehicle from the dealer in January this year.. You are sitting quietly minding your own business when the engine chimes in normally this only happens if you are listening to your itunes or car radio with the power on( the vehicle announcing its not in go mode)   having previously switched it off. . My car still does strange stuff which i am currently ignoring just as an example i pulled up to some traffic lights recently and engaged the p button to park not the the gearstick. The car after about 15 secs suddenly lurched forward having decided to disconnect from parking mode and i had to employ my 72 year old reflexes to prevent a rear end shunt. Nothing surprises me today as i had a Golf 2l TDI that had a problem with its GTD box so when you selected reverse the AI in the gearbox would decide to lurch forward and then decide that was wrong and go backwards. I just had to remember in future to give any vehicles parked in front plenty of space.

My Corolla also puts the front mirrors into park automatically when you exit the vehicle but wont self lock using the fob weird or what its  like the design engineers forgot something after their Friday meetings at HQ. The locking procedure is totally random when using the fob sometimes it will lock other times i have to go back to the vehicle and press the on/off button while cursing profusely and no i have not left a door unlocked or window down !😫😩

When stationary I would always ensure the handbrake is on. I dont know whether the Corolla has an actual HAND brake, in the Gen3 and Gen4 Prius (had both) the "handbrake" is foot operated.

[Louie]

Guys i am ready for anything so every time i go out i wear a parachute in case the little red button on the gear shift ejects me when i press it. Her indoors while sitting in the passenger seat has a saying which i am getting used to and it goes like this "was it supposed to do that ?" 😂

[King Crimson]

54 minutes ago, Catlover said:

When stationary I would always ensure the handbrake is on. I dont know whether the Corolla has an actual HAND brake, in the Gen3 and Gen4 Prius (had both) the "handbrake" is foot operated.

It's an electric handbrake, i've never pressed it as it engages when the gearshift is in Park and disengages when in R,D,N. 

[King Crimson]

21 hours ago, Louie said:

My car still does strange stuff which i am currently ignoring just as an example i pulled up to some traffic lights recently and engaged the p button to park not the the gearstick. The car after about 15 secs suddenly lurched forward having decided to disconnect from parking mode and i had to employ my 72 year old reflexes to prevent a rear end shunt.

 

If you want your car to engage the brakes when stationary you can press that hold button which is right next to the p button, when coming to a complete stop and wait for a second you will see a small sign in the instrument cluster which reads "HOLD", when that sign appears you let your foot off the brake pedal and the car will stay still. However one thing that gave me a scare once is when i got in my car pressed the start button and not moving at first as i was checking something on my phone, the engine came in and i felt the car squat a bit as if i was giving it gas but it didn't go anywhere, scared the **** out of me as i was not paying any attention.