ICE does not turn off, after turning on to protect full battery

How long do you wait? If engine starts it needs to run for a while to wam it up to keep the engine healthy. In my experience it shuts off in about 10 to 15 miles of highway driving and reverts back to EV mode then. Have you waited that long without taking steps to interrupt it?

If it stays running for your whole 60 mile commutes, I feel something is wrong with the car. Complain to Honda...

 

I'd suggest you set a timer in the app to start charging about 1:45 before you leave (more or less) so that you get to ~95% right when you leave home, that way it will not start the ICE on that first hill.

 

Sometimes toggling HV mode on and off gets the gas engine to turn off. Try that.

 

I've been dealing with this not from a hill, but just from regen being too strong when the battery is fully charged. In my car, I haven't been able to decelerate to a full stop from about 40 MPH right at half mile or so after charging to keep the ICE from kicking in. I tried stopping charging at 95%, but that didn't help. Today I stopped charging at 87% and I'll see how that works. I really don't need all the battery range since I have a short commute, so it's not a huge deal to stop charging if I can remember to catch it. The regen thing is kind of a death spiral if you aren't careful. The ICE kicks on due to the battery being near full state of charge with too much regen. The ICE has to run enough to warm adequately. When it is running to warm, it will add some regen back into the battery (not exceeding regen levels, so slowly) and pretty much fully recharges the battery since it was near full SOC already. So now you are at an even more sensitive state for regen starting the ICE again if it is much at all....

 

The engine can cycle on and off quickly only after warmup. Modern 4 cylinders are notorious for fouling plugs if started cold and shut off quickly. Gotta get the plugs good and hot to burn off deposits, plus get moisture out of oil and get it hot and flowing good, etc. Once hot the short starts are harmless. Dont interrupt it. Its running for a reason. If it shuts off 10 or 15 miles into commute it is working as designed and burns very little fuel because rpm stays low. It’s not an electric car...engine needs to run at times.

 

The 87% charge level was low enough that the ICE didn't start for regen at the same location that it usually does. I'll have to experiment more to make sure this always works for me to prevent ICE or to see if I can push up the level a little. Like I posted earlier, I tried 95% once and that failed.

 

Then don't time the departure--shut it down manually in the app when an alarm goes off an alarm (wakeup?) and work backwards from that point. Just be aware that the charging restarts when you precondition.

Or get a smart charger and use that to manage it.

 

Yes, I used the hondalink app today to stop the charging. Still takes a little attention to hit it right since your time window is fairly narrow if charging at 30A.

 

Experiment with a low partial charge and see how much you regen. Then you will know how about much headroom to leave.

Alternatively you can control a level 1 charger pretty easily when it is plugged into a Wemo.
Then again a level 1 charger is so slow that you may not need to shorten the charge at all.

 

@michael shama, I was posting in another thread about the ICE starting from regen when the battery is nearly fully charged. Rather than drag you through the details, someone asked about running the heat. If you can anticipate where you are decelerating enough to cause the ICE to start, you could turn the heat on just before that time. This might give enough room for the regen to not start the ICE. Then turn it off after you get through the place where the deceleration started it. For my car, this is the same location every time, after stopping from 40 mph for a left turn. It will be easy to try this solution for me. i think if I can avoid this one event, that the rest of the drive will be no problem as the battery will continue to discharge and leave more and more room for regen.

 

I tried it yesterday, but I think started the heat too soon before the braking event (like 15 seconds prior to braking) and the ICE started. I'll push it today back to about a minute earlier and see if that is enough.

 

I have a small hill about 1 minute into my daily drive I have to go down that sometimes triggers the engine to start. What I don’t understand is why after the engine warms up and shuts back off does the power gauge not go back to blue? Instead it stays white and the engine randomly starts back up for brief periods of time up to the end of my 12-15 minute commute. I wonder if I’d be better off just putting the car in neutral going down the small hill (there’s a stop sign at the end of that small hill). In my opinion, Honda should have just programmed the friction brakes to take over in these cases rather than starting the gas engine.

 

ManKo,

I think the ICE goes into HV mode, even though HV indicator does not activate. To stop the ICE from activating during the entire commute, try manually putting in HV mode, and then taking it out of HV mode.

Switching to neutral for going down the small hill does seem like it would avoid the whole issue.

 

Eureeka! I have stopped the ICE from starting for my regen immediately after charging through the heater. This happens every day, so it is very predictable for me. It's about 1/4 mile into my commute home. I started the heater at relatively high fan speed about 30 to 45 seconds prior to the time of regen. No ICE start. Then simply turned the heat off. Thanks to @The Gadgeteer and @MNSteve for helping to suggest this solution to me. I'll play with the amount of fan speed required to see if I can back that down to a slower setting. The heater is on for so short a time that the environment in the car really doesn't change so that isn't going to be a problem. Hopefully the results are 100% repeatable and I can take this aggravation off my list...

 

I have to assume fan speed is irrelevant as that’s running off the 12v and uses very little juice. It’s just the heat coils for the coolant you want to turn on since they draw something like 7,000 watts out of the big battery when first activated. That shouldn’t change with any fan speed you choose.

 

I noticed in my car that once ICE turns on, it will stay on for awhile, until ICE has warmed up and the dash will show the white line instead of blue. But eventually, it does to back to EV mode. Be patient