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Please only answer the poll if your car is at least two years old.
Hypothesis: Timed Departure/Preconditioning Maintains the 12V Batteries
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19 I-pace HSE Polaris/Fuji white with most options and a lot of accessories
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Using my 12V battery monitors, it is clear that any time the car powers up the car does apply a charge to the 12V battery/batteries just like an ICE alternator activates when the engine starts. These times are when the driver unlocks the car, when the driver is sitting inside for a long period of time and then presses the start button, when the car is in a charging session, during traction battery preconditioning, and when the cabin climate system is activated. Basically, any time when the hazard light is lit, cabin climate is active and during charging sessions there is charging applied to the 12V battery/batteries from the DC-DC converter.
Cars that sit a long time without activity for 4 days go to sleep and odd thing happens at 12 hour intervals. There's a brief dip in the voltage readings observed by my monitors. I have no idea what happens for that minute or two that the monitors capture a power draw. The transition from 2022 to 2023 actually triggered a very brief charging event even though the car was in deep sleep mode without explanation. This did not disrupt the 12 hour interval.
Also, a scheduled preconditioning event does not affect the 4 day idle counter. The preconditioning event(s) will occur as scheduled for a car that is plugged in, and the 12V battery/batteries will get a charge. I haven't set up a repeating preconditioning that would span into the deep sleep time so I don't have data on what happens for that condition.
Cars that sit a long time without activity for 4 days go to sleep and odd thing happens at 12 hour intervals. There's a brief dip in the voltage readings observed by my monitors. I have no idea what happens for that minute or two that the monitors capture a power draw. The transition from 2022 to 2023 actually triggered a very brief charging event even though the car was in deep sleep mode without explanation. This did not disrupt the 12 hour interval.
Also, a scheduled preconditioning event does not affect the 4 day idle counter. The preconditioning event(s) will occur as scheduled for a car that is plugged in, and the 12V battery/batteries will get a charge. I haven't set up a repeating preconditioning that would span into the deep sleep time so I don't have data on what happens for that condition.
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If I remember correctly, if you set multiple preconditioning, but you don’t boot up the car in between, the second one , and subsequent will never precondition the car. It is to prevent from draining the battery if you leave the car in a parking lot for example for a few days or weeks.
Before I answer, I want to be clear by what you mean by "regularly?" Is once a month regularly, or does it need to be more frequently, say more than once a week? If I preconditioned sporadically but it totaled up to say 7 days in a month, would you count that? Sorry to pedantic, but I am 
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I think we do it once a week, which I consider regularly. 7 times a month is regularly if spread out some. Once a month or 7 times in a single week but not otherwise is not regularly. Just go with your gut if you aren't sure.Before I answer, I want to be clear by what you mean by "regularly?" Is once a month regularly, or does it need to be more frequently, say more than once a week? If I preconditioned sporadically but it totaled up to say 7 days in a month, would you count that? Sorry to pedantic, but I am
I answered "b" but my specific use case is not in the selections. If I do not drive my car for 3 days or more (I usually only drive it on the weekend since I work from Home and would use the family gas car on infrequent occassions that I have to leave the house during the weekday), I hook up the large 12V to a battery maintainer using the quick connect that I added to the battery. I am still on the original batteries (but I only have the maint on the large battery, if that matters.
Edit: I should also note that while the starter battery is being charged by the battery maintainer, the hood is always open. Not sure if the hood being open could trick the car to keep the Aux battery charged as well? Or if the Aux battery is being charged from maint connected to the starter/main battery.
Edit: I should also note that while the starter battery is being charged by the battery maintainer, the hood is always open. Not sure if the hood being open could trick the car to keep the Aux battery charged as well? Or if the Aux battery is being charged from maint connected to the starter/main battery.
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On my MY22 the preconditioning comes on as scheduled when hooked up to a charger, even if the car wasn’t started in between.
My understanding is that preconditioning is not supposed to work if it’s not plugged in to a charger. Perhaps what you said happens when it isn’t hooked up to a charger? I’ve noticed that my preconditioning happens even when not plugged in to a charger. But I haven’t checked multiple days without starting the car in between.
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My I-Pace is over 4 years old. I regularly precondition. The battery has been fine so far. I've had car batteries last for 8 years, though I've never owned an EV for that long.
This isn't a perfect study by any means, but there's an interesting trend in the little data we have. 27 people. 14 failures. Only 1 failure with a preconditioner.
You all know that setting a departure time makes you precondition, right?
The use of preconditioning may be a red herring, the issue may be regular vs irregular usage. Wouldn't daily use keep the batteries at a "good" level, unless there is a suggestion that preconditioning charges the batteries in some unique way.
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I was wondering the same thing. My 12V batteries seem fine and my car is driven every day, but I only precondition for a couple of months out of the year and only on my drive home from work (July/August) and only for five or ten minutes. Preconditioning does seem to immediately charge up the 12V system, but I don't know if that's different/better than driving the car for 20 minutes (the length of my commute one-way).
In my case, yes the aux battery has been replaced; but as part of the repair involving the wiring harness issue. Prior to that it was unusual for the car to sit more than 2 days without use.
Whether the aux battery problem resulted directly from the broken wiring harness, or as a result of sitting unused I cannot say.
One note though; while waiting for the repair, I saw that WattCat reported an almost weekly (to the hour) charging event for the main 12v battery (aux battery according to WattCatt). Was this the car sensing a low aux battery and trying to charge it?
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Yeah, I don't think we have sure proof. I just think we have some evidence. We could create another thread with another poll that drills down further, but I'm not sure it would really answer the questions for sure either, especially considering we're going to get 30 or fewer responses.
I find it pathetic that a technical question like this has to be answered by twatter poll rather than by Jaguar engineers. What has the world come to? Why do people think that lots of voices is an acceptable solution to a question about technical specification? It is not. Demand the answer from the manufacturer and if they are unable/unwilling to tell you then ask why and if still no acceptable answer is forthcoming then threaten to ridicule them on social media and shop elsewhere.
It really is unacceptable that so little information is given to the public when purchasing such expensive complex products these days. Where is the technical manual? And I don‘t mean the legal arse covering online pamphlet that tells you just about enough to get the thing started.
Yes, things can get changed by software updates, but such changes should be documented, with version numbers and dates, and all the old fashioned engineering basics.
It really is unacceptable that so little information is given to the public when purchasing such expensive complex products these days. Where is the technical manual? And I don‘t mean the legal arse covering online pamphlet that tells you just about enough to get the thing started.
Yes, things can get changed by software updates, but such changes should be documented, with version numbers and dates, and all the old fashioned engineering basics.
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You expect corporate competence and care? Should you find a large company, automotive or otherwise, that exhibits these qualities, please let me know.
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How do you figure that?
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I dont precondition at all. 2.5 years old. Never any issues or problems. We do long runs regularly. I figure that if you do a lot of short journeys, the 12v battery never gets a chance to charge. A 10 min run will do nothing for a depleted LeadAcid. 2 hours much better! Melbourne Australia.
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