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Car now sleeps for days ... new behavior.
- Thread starter RogerMc
- Start date
roblab
Active Member
We always wake our cars up with a strong cup of morning coffee. Only problem is that if we do this too often, it gets the jitters.
Not sure if this is a problem experienced by many, but I've had TeslaMate running for my car since I got it and over the past 2 years I have noticed that it has spontaneously woken itself up to charge the 12v battery after several days, which then progressed to every 48 hours, and recently every 24 hours. I barely drive my car - having only done 2775 miles in those 2 years - so the car is sat idle most of the time, so it's easy for me to notice that these wakeups correlate to 12v recharging. Tesla even confirmed it for me when I provided timestamps of when it was doing it.
All well and good so far - the car is maintaining the battery, stopping it from dying and me being unable to get into the car.
Unfortunately, since receiving 2022.4.x, the car no longer behaves this way. As of this post it has been asleep for 60 hours. On the basis that I can't imagine the 12v battery has suddenly stopped needing to be topped up every 24 hours, when it was behaving like that for several weeks, I'm getting a bit concerned.
I know if I talk to Tesla they'll just spin me a line to say that the car knows when to wake up and will do so when it needs to - end of story. That's all well and good until I can't get in to the car.
I have got cold feet after about 48 hours asleep previously, and woke the car with the app. When I do this, the car will stay awake for 2-3 hours each time, which suggests it really does need to charge the battery but is in such a deep sleep that it's not doing it itself. I am reluctant to leave it much longer than 60 hours on the off chance that it depletes the 12v so much that I can no longer get in.
I should add - if I leave the car plugged in to the charger it seems to wake up every 24 hours at the scheduled charging time to see if it needs to charge, and in so doing will recharge the 12v then - judging by TeslaMate. I don't really want to have to leave it plugged in if I don't need to though, as it's not going anywhere.
In my opinion there's definitely been a change of behaviour in 12v topups - which looks to me like a bug - for the simple fact that, as said before, I can't conceive of a scenario where the car needed to wake up progressively more regularly (few weeks -> every week or so -> every 48 hours -> every 24 hours) to top up a degrading battery, and now it suddenly doesn't.
Any thoughts gratefully received
All well and good so far - the car is maintaining the battery, stopping it from dying and me being unable to get into the car.
Unfortunately, since receiving 2022.4.x, the car no longer behaves this way. As of this post it has been asleep for 60 hours. On the basis that I can't imagine the 12v battery has suddenly stopped needing to be topped up every 24 hours, when it was behaving like that for several weeks, I'm getting a bit concerned.
I know if I talk to Tesla they'll just spin me a line to say that the car knows when to wake up and will do so when it needs to - end of story. That's all well and good until I can't get in to the car.
I have got cold feet after about 48 hours asleep previously, and woke the car with the app. When I do this, the car will stay awake for 2-3 hours each time, which suggests it really does need to charge the battery but is in such a deep sleep that it's not doing it itself. I am reluctant to leave it much longer than 60 hours on the off chance that it depletes the 12v so much that I can no longer get in.
I should add - if I leave the car plugged in to the charger it seems to wake up every 24 hours at the scheduled charging time to see if it needs to charge, and in so doing will recharge the 12v then - judging by TeslaMate. I don't really want to have to leave it plugged in if I don't need to though, as it's not going anywhere.
In my opinion there's definitely been a change of behaviour in 12v topups - which looks to me like a bug - for the simple fact that, as said before, I can't conceive of a scenario where the car needed to wake up progressively more regularly (few weeks -> every week or so -> every 48 hours -> every 24 hours) to top up a degrading battery, and now it suddenly doesn't.
Any thoughts gratefully received
perhaps they are better managing the vamp draw and it does not need to wake as frequently.
I have one of these -
I’ll look at our 3 when my wife is home this evening.
I have one of these -
I’ll look at our 3 when my wife is home this evening.
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Thanks, not just me then.
I have an aftermarket automatic trunk and frunk lifter on my car, which uses a nominal amount of power when idle (frunk is connected directly to the 12v battery, trunk is connected to penthouse 12v which seems to be alive when the car is), so I know at least the frunk kit must be sapping power.
I know for a fact that there is vampire drain on the 12v battery as a result, and that I have enough data to know that the 12v recharging periods have become more frequent. Tesla have tried to reassure me that the car manages all of this itself and that it will tell me when it needs replacing, but at the same time bugs exist, and I have heard apocryphal stories of 12v battery failures without the warning showing up.
The car would only stay awake for 10 mins or so. And it wasn't after a predictable 24 hr interval, nor at the scheduled charging time either.
Hopefully 12v battery isn't an issue for at least a few years.
thanks for letting me know. Whoever merged the threads has basically messed my chances of getting feedback up, it’s not even in the battery subforum now 
I lost my nerve at 60 hours and woke the car up by opening the door. It opened fine, but stayed awake for an hour afterwards.
If this is an undocumented change or 12v maintenance improvement in 2022.4.x I wish a Tesla tech could confirm it.
If this is an undocumented change or 12v maintenance improvement in 2022.4.x I wish a Tesla tech could confirm it.
I'm guessing they must have made the power draw during sleeping more efficient. I've had my 2022 M3LR for a little over a month and have TeslaFi logging and the new 12V lithium battery. Couple of weeks ago, I went out of town for several days, with car not plugged into the EVSE, sentry off, and doors unlocked in my garage. According to TeslaFi, the car was asleep for 49 hrs 38 min. It woke for 23 minutes, then went back to sleep for 16 hours, and only woke up because I opened the door to drive the car. Given that the 12V lithium battery only has a capacity of around 100Wh, the power draw during sleep seems to be at most 2W? This is in contrast to previous posts which said that the car draws 8-20W. Since the 12V lead-acid batteries have greater capacity than the 12V lithium battery, it may not be surprising that the car would sleep for more than 2-3 days. Maybe someone with more electrical and/or automotive knowledge can correct my reasoning if I'm off-base.
That is all very interesting. I remember people a couple years ago complaining that their 12V would fail quickly. I think this was related to Tesla deep cycling the battery even though it was not a deep cycle 12V. That would indeed kill it quick. I felt better seeing the car charge it daily.
As said earlier I see my car wake up like before... Might be because my 12V is more than two years old though...
As said earlier I see my car wake up like before... Might be because my 12V is more than two years old though...
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