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

You might try these 2 suggestions that we have evidence have worked for some.
1 Do a hard reset; not the head unit reset. Disconnect the negative terminal of the battery for 5 min and reattach. You will get a lot of warning messages on start up, but it’s OK; no damage and they will go away with some driving.
2 Make sure you have all the Service Bulletin updates installed. This is hard to verify and several have had updates that did not take or were not done to completion. You can check the HV update by adding gas and not see the HV range erroneously increase to unbelievable numbers. You can check the overly sensitive charging update by charging at various public chargers and see if it cuts off before a full charge. I don’t know if a way to test the other updates.

Here is some info I found on the forum on the US updates:
Posted by D. Red on 10/26/18
He still brought the car in and check the CEL, and it came back with the following:
18-089: 6SV00, PHEV Abnormal Water Temperature Reading PUD
18-091: 6PH00, Range Display Incorrect PUD
18-090: 6VT00, EVTC Failure Misdirection PUD
18-096: 6CW00, Emissions Warranty CD Product Update
18-069 superseded by 18-091 according to Steven B on 11/19/18

Posted by Sandroad on 12/11/18
Last October, Honda grouped the software updates and some defective parts into some sort of service campaign. I'm not sure about the specifics. Although someone else on this forum called it a recall, my VIN shows nothing official for a safety recall. I should not have used the word recall in my post above.

Here are the open service bulletins that I THINK are included:
18-089: 6SV00, PHEV Abnormal Water Temp Reading
18-091: 6PH00, Range Display Incorrect
18-090: 6VT00, EVTC Failure Misdirection
18-096: 6CW00, Emissions Warranty CD Product Update
18-097: charging problems (sensitivity to power fluctuations at public chargers)
And on 12/13/18
They did 4 updates (descriptions in a post above) for our VIN:
18-091
18-090
18-096
18-089
The 18-089 update required a part, a CPU assembly 06999 that is part number 06796-TRW-A00
The 18-096 update is also a “part” because it’s a new warranty CD.

1/11/19 posted by vice
SB 18-090 PHEV EVTC Failure Misdirection PUD
SB 18-091 PHEV Range Display Incorrect PUD
SB 18-096 PHEV Emissions Warranty CD Product Update
as OPEN RECALL
and
SB -097 PHEV Clarity Fails to Charge or Finish Charging
as a CUSTOMER REQUEST
They couldn't perform SB 18-089, due to a back-order on the CPU part, but they will call & schedule that as soon as it is available

Try those and post back please. Best wishes for some resolution for you.

 

Tim66:

My understanding:
It seems the ICE does need to warm up, anytime that it is started. So, the only way to shut off the ICE for the first 2-5 minutes of runtime is to shut off the car. After that it should be in HV mode (even though the HV mode light does not come on), and it should be possible to shut off by getting out of HV mode. Since the HV mode light is not on, it is not clear when you are out of HV mode, unless you get the HV mode indicator to come on, and go off. In HV mode, the ICE will run until the battery charge is close to the level it entered HV mode at, and I am not sure the battery is charging well during the ICE warmup time.

I have had the ICE stay on, for an 'extended' amount of time, because the battery level had dropped (still over 50% charge) during the warmup time.

 

Ken I did the hard reset a week or so ago to fix my stuck on 277 mile HV range problem. It worked. I'll check with the dealer to see if all updates have been performed.

ClarityBill, I had travelled about 15 miles on the freeway when my problem happened. Surely the engine and motor were warmed up by then.

Tim

 

I generally blast the heat/a.c. and accelerate quickly to try to burn some battery before hitting my early morning downhill 1/4 mile.

Sometimes I'll run both seat heaters and quickly accelerate around the block real quick.

The amount of gas that I'm saving by not having the ice crank up is peanuts, but it's just mental satisfaction to see how little I can use.

It would be nice to be able to charge to a % of full battery like in the Tesla

 

Re: ICE turning on despite starting out in EV mode: this isn't really bothersome, especially now that we know there is something about starting out on a downhill that triggers the ICE, rather than some potential issue.

In our case, the ICE kicks in when the battery is sufficiently charged, but by no means fully charged. We're not using the app to monitor the charging process. Since leasing our Clarity, the most it's been charged is when it reached a range of 61 miles. Usually, we get to a range of 46 or so miles from charging. (full disclosure: this is embarrassing to admit but what the heck: at home, we are charging our vehicle using extension cords and the charger. Yes, I know one is not supposed to use the charger with extension cords. Yes, I know there is significant loss of electrons over the length of the cords. Our bad. But the fact is, we simply do not have an outdoor plug near enough to the street that allows us to plug the charger directly into the outlet. Good news is: an electrician will install a new outdoor plug this week )

Additional mildly interesting data point: very rarely, when I arrive at work, a public institution with a total personnel level of almost 18,000, one of the 8 charging spots will be available. For whatever reason, even after three hours, the battery does not add more than 4 miles of range. The good news is, if I occasionally park at a store that has chargers, the Clarity can gain over 8 miles of range in under 20 minutes.

 

Has your dealer installed the Service Bulletin fix for Clarity PHEV charging issues?

 

No, not yet. But we will attend to that very soon. We have identified a good local dealer and have to schedule an appointment.

 

If you only get 4 miles in 3 hours of charging: Did the charging actually stop? (Was the green light off when you returned to your car?) I have been able to remotely restart charging with the HondaLink app. I have also had better luck when I make sure to uncoil the entire cord from the charger. Clarity's are known to have trouble with some charging stations (voltage spikes, communication problems?)

 

MGT:

When you said, "In our case, the ICE kicks in when the battery is sufficiently charged, but by no means fully charged." The amount of charge should not be judged by the EV mile projection. The amount of charge should be judged by the bars lit on the left side of the dashboard. The EV miles are a calculation based on your past driving, and not a good indicator of battery charging.

Does your ICE kick on in EV mode when there is less than full charge on the left side of the dash?

 

The charging did stop, as determined by the green light being off. But the vehicle energy reading (on the center console screen) showed only a gain of 4 miles and the battery gauge at the left side of the dash did not show full. I attribute this to the chargers at my workplace being in a state of disrepair; at least one of them does not work for anyone, and two others have intermittent issues.

Thanks for this info! I've only once seen the bars on the left side of the dashboard indicate a full battery, and that was when the Vehicle Energy showed a battery range of 61 miles. For whatever reason, the majority of the time we charge the vehicle at home, the battery bars show the battery at approximately half to 3/4 full, while the range shows 41-46 miles.

Yes, the ICE kicks on just about every time I start out downhill, typically with about 3/4 charged battery. Somewhere, on one of these threads, someone had posted a very plausible and apparently quasi-official explanation for this, which eliminated my concern that there was some potential issue with the battery.

We're looking forward to getting the accessible electric socket so we can directly attach the charger.

 

During downhills to waste momentum energy that cannot be converted to electricity back to the battery thus saving your brakes the computer is using the electric motor/generator to spin the engine. The engine is not "running" anymore than a standard ICE car engine is "running" while coasting while in Drive. The fuel cutoff is cutting off the fuel. If anything it is keeping your engine lubricated and running well for as close to free as possible.

 

I beg to disagree, when mine does this, my hour meter (inductively coupled to the #1 plug) increments and the exhaust manifold gets almost too hot to touch. To me this indicates the engine is running. Am I missing something? BTW, the same two observations occur when the engine comes on for the limited regen with full SOC to protect the battery thingy.

However, I’ve only gone down a big enough hill in EV one single time so I can’t say for sure if it’s an every time thing or just a one off.

 

Yes, the engine is definitely running after starting for regen. I think that at the beginning it may behave as @Gadgeteer describes, then it trips the "I must run long enough to adequately warm up" subroutine and runs for a few minutes until it gets that subroutine satisfied. Of course, during this running, it is likely to charge the battery some more, causing the next regen to start the engine again if it is aggressive braking at all. At least the runtime doesn't seem as long since the engine is warm at this point... This regen starting the ICE behavior seems much easier to incite in colder weather as the Clarity seems to be more protective of the battery charging near full state of charge in cold weather than in warmer weather. I've been able to avoid it for the most part by proactively turning on the defroster prior to a particular predictable regen event that causes me issues (immediately after a full charge). In the warmer weather recently, I have had mostly success just trying to be a little easier on the regen and not running the defroster. In colder weather, the regen event always starts the engine if I don't have the defroster on for 30 seconds or so prior to the event...

 

I am sure the amount of fuel consumed during these events in minuscule, however, the desire for the engine to not run is enormous for most of us. The work around Robert suggests and I and others have suggested in the past if this is a predictable downhill regeneration event at full charge then this is also a perfect opportunity to do use some extra climate control just before the downhill.

I personally have not experienced this so I am not feeling everyone’s pain on this but when I start taking the Clarity to the Pocono mountains some weekends I expect to run into this pretty regularly at the start of the day assuming I can get a full charge; the townhouse is at least 50 feet from the nearest parking spot and charging will be level 1. With my ICE vehicle I have to rely on engine braking and friction brakes a good amount so it will be interesting to see how this pans out.

 

Tim, I just posted about this! before I found your question buried in this thread. Here is the link: https://www.insideevsforum.com/community/index.php?threads/sudden-hard-acceleration-starts-ice-but-it-wont-turn-off-why.5369/#post-58305

I still think this is a bug. There is no logical reason, after a brief quick acceleration, to leave the ICE running for so long. But next time I will simply leave it alone and time it. This has happened every time I accelerate into the white section briefly (and I mean briefly). I will also be going to the dealer to ensure I have updates I need, as I purchased in Oct 18 and I believe there have been several updates since then...