Last night, my door was not shut all of the way when loading groceries into the house. I suppose that the interior light was left on, although I didn't pay much attention to it.
Anyway, I pull the car out of the driveway, put it in park to go manually close the driveway gate, and when I returned the ice was charging the battery- green line going into the battery on the display.
I had a full charge. Perhaps, the all-night light drained the battery, and the ice kicked on to recharge it???
I've had the ice kick on many times while in park, but it has never happened this quickly. Normally it takes 10-20 minutes of being in park with the car "ON."
As I mentioned before I believe it is your 12v. I had an interesting experience so I will post everything that happened for discussion. It may all be coincidence but I think it suggests that the culprit is one of the two batteries (specifically the 12v leeching off the lithium battery).
I have posted in other threads that I believe that the ICE kicks on when you have a full charge and excess energy from regen braking. I still believe this is true but there might be a wrinkle to this.
I have a Scangauge which has a measurement of the the max and min percentage of the individual cells state of charge. So it is reporting the highest reading of the most charged cell in the entire pack and the lowest of the least. This is the true state of charge and is not what is reported in the app. It is labeled MXS for max state of charge and MNS for min state of charge. Note that the MXS of 96.0% corresponds to 100% SOC on the app. At the bottom of the battery pack a MXS of 20% corresponds to the app SOC of 10% and when the car starts the engine automatically.
For the past year the smallest spread is at the top of the charge, Max 96.0% - Min 95.4. All 166 of the other cells are between that range. The largest spread at the bottom of the charge has been 1.8%, MXS of 20.0%, MNS of 18.2%. That is when it is warm outside. When cold, the spread has has increased to nearly 2.5%, 20.0 - 17.5. On the day of this occurrence the spread reach 3.1%.
I rarely let the state of charge go below 45% on the app which corresponds to a 50% MXS. The past couple of weeks I have been charging to 90 and running it all the way down to the ICE turn on just because of the nature of the drives. The other day I did my byweekly full charge. Turned car on but had to run back in the house. Got back in the car and while programming my GPS in park the ICE turned on. Caught me by surprise. Looked are my Scangauge and the spread 1.3%. 95.8% to 94.5%. That is double the normal top of charge spread.
My thought is that maybe it’s possible the car is finishing the balancing of the battery. Of course this is one occurrence that might be just a coincidence. Possibly a combo of a larger than normal spread at the bottom of the pack and the 12v leeching on it.
My 12v is getting kind of weak as it reads 14.3 max when the car is on. 12.2 when the car is off and 11.8 when the car is in accessory mode. I will say that since I experienced this I have not depleted the battery as much and charged to full every night instead of just twice a week. The top of charge spread got progressively better each night and after 4 nights it was back to the 0.6% that I am used to seeing. Again, this may all be coincidence and amount to a hill of beans but I thought I would share. I will also add that it was bitterly cold, I usually park in hearted garage but had not been for a week because of a project and the Scangauge reported the the temp of the lithium battery at 32. It may have been colder but the Scangauge can’t read below 32.
I haven’t looked over this post in a while, so I can’t remember if you have taken the car to the dealership. If it were me I would take it to the dealership and have them load test the 12v. Also I would ask them for a live readout of the lithium battery. They will look at you as if you just spoke Martian. Ask them to hook it up the HDS, go to the Electric Powertrain menu and record the live data while the car is on (the ice does not have to be running). The data takes up about 8 pages. If you get a chance to do all this post the data to this thread and we can all take a look at. If I were a betting man, I would put all my money on them telling you that it is normal behavior (absent an issue with the 12v.)
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