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12v battery software update recall

ScottHelme

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My car went in to Porsche for a recall this week after they reached out to me directly. They said it was a software update related to the 12v battery, but wouldn’t give me any specifics. Does anyone know what it was regarding?

I’ve had a lot of issues with the 12v battery so I was keen to get it in and done. They also installed the OTA update that I kept installing and then the next day it would tell me there’s an update to install 🙄
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anonymouse

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I was told that The update addresses a problem that under some conditions the 12V battery may incorrectly report its charge status, leading to it going flat if not driven for a long period.
 
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ScottHelme

ScottHelme

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I've had several recoveries for my car because the 12v has gone flat, some as soon as 2-3 days since it was last driven! I regularly get the 'low battery' on the screen and it won't let me use the rear window heater or heated seats too.

I really hope this fixes it...
 

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Hi guys, on this, my first Forum post.
I, too, have had similar issues to you Scott (sadly, amongst many others on what I increasingly believe is a "Friday afternoon"-built car), on my (first Porsche & first electric) Taycan CT 4S (MY23). It beggars (at least, my) belief that such a brilliant (& EXPENSIVE) car is at the mercy of a (deeply flawed, IMHO) 12v system. As the driver, neither I, nor the car nor the app has any way of having its battery health monitored or verified (UNTIL it goes wrong) without plugging in a (ludicrously expensive) maintenance trickle charger.
The work-around from Porsche Centre is to a/ buy the £160.00 (discounted) trickle charger from them (my "Porsche Approved" purchase is under 4 year warranty so I want no quibble about 3rd party damage) AND b/ to leave the 12v "plugged in" all b***** winter when not in use!!! My wife has an MG4 LR (also electric) which, at 20% of the cost, does at least have a 12v monitoring system AND a 12v battery that seems to charge as it is driven. So leaving it continually plugged in is untenable for us, anyway. Whilst this software update may have enhanced battery reporting (too soon to tell?), it still does not allow me to find out the 12v status (as far as I know).
It could just be me but ANY ideas on how this deplorable situation might be bettered, gratefully received.
 

W1NGE

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Hi guys, on this, my first Forum post.
I, too, have had similar issues to you Scott (sadly, amongst many others on what I increasingly believe is a "Friday afternoon"-built car), on my (first Porsche & first electric) Taycan CT 4S (MY23). It beggars (at least, my) belief that such a brilliant (& EXPENSIVE) car is at the mercy of a (deeply flawed, IMHO) 12v system. As the driver, neither I, nor the car nor the app has any way of having its battery health monitored or verified (UNTIL it goes wrong) without plugging in a (ludicrously expensive) maintenance trickle charger.
The work-around from Porsche Centre is to a/ buy the £160.00 (discounted) trickle charger from them (my "Porsche Approved" purchase is under 4 year warranty so I want no quibble about 3rd party damage) AND b/ to leave the 12v "plugged in" all b***** winter when not in use!!! My wife has an MG4 LR (also electric) which, at 20% of the cost, does at least have a 12v monitoring system AND a 12v battery that seems to charge as it is driven. So leaving it continually plugged in is untenable for us, anyway. Whilst this software update may have enhanced battery reporting (too soon to tell?), it still does not allow me to find out the 12v status (as far as I know).
It could just be me but ANY ideas on how this deplorable situation might be bettered, gratefully received.
Many brands of EVs have 12v battery issues - more common than you might appreciate.

Battery is different tech to what you are used to.

You should not need to trickle charge especially if the car is used regularly.

None of this helps but hopefully the software patch addresses the issue and if not then the battery itself must be at fault and therefore a warranty claim.

I've had 2 Taycans and 4 years of ownership and never a 12v issue.
 


BraveSirRobin

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Many brands of EVs have 12v battery issues - more common than you might appreciate.

Battery is different tech to what you are used to.

You should not need to trickle charge especially if the car is used regularly.

None of this helps but hopefully the software patch addresses the issue and if not then the battery itself must be at fault and therefore a warranty claim.

I've had 2 Taycans and 4 years of ownership and never a 12v issue.
Thanks W1NGE (nice name - chimes with my current attitude?). Pleased to hear about your lack of issues; perhaps my (partial?) solution should be to drive it more often? Still, I don't understand why the App will not allow me to monitor the 12V health & why the Chinese MG4 can do it. Still, if the battery were the only issue, I might be much happier - except for the £800-£1,000 price tag on a replacement (small wonder Porsche always tell me my 12V is "within specification"?).
 

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Still, I don't understand why the App will not allow me to monitor the 12V health
That may be somewhat understandable when the engineers never expected the battery to drain in the first place since the HV battery would always top it up. There is something bigger going wrong in your circuitry than that battery.
 

BraveSirRobin

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Thanks, ovonrein. You're telling me!!! I did a 150 mile (of closer to 4 than 3 hours driving) round trip last week with a 5-6 hour between arrival & departure. When I got home my battery (according to the trickle charger, which I then plugged in), was still in the bottom quartile of charge. I have no idea what it takes for the drive batteries to impact the 12V but I would have thought that should have made more of a difference? Then again, what do I know? I am still a learner here!
That said, I have all manner of non-thread issues.
(BTW: your Forum joining-date was about the time I bought my Taycan - I can see you have been busy posting/participating since then!)
 


ovonrein

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Right tube set 12v battery status. 14+ its charging 13 its charged. Charges every time the car wakes up. IF you keep the keys close to the car (3 metres) it does not go to sleep and can act as a parasitic drain. A biscuit tin is your friend. (for the keys) or switch off keyless access.
 
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W1NGE

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Thanks W1NGE (nice name - chimes with my current attitude?). Pleased to hear about your lack of issues; perhaps my (partial?) solution should be to drive it more often? Still, I don't understand why the App will not allow me to monitor the 12V health & why the Chinese MG4 can do it. Still, if the battery were the only issue, I might be much happier - except for the £800-£1,000 price tag on a replacement (small wonder Porsche always tell me my 12V is "within specification"?).
W1NGE is my vehicle reg number 🤪.

Using the app regularly to monitor or set anything is not to be recommended either - ironically has a direct consequence for the 12v battery to pull back all telemetry.

The app is pretty rubbish but has improved since 2021 to be fair.
 

W1NGE

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Thanks, ovonrein. You're telling me!!! I did a 150 mile (of closer to 4 than 3 hours driving) round trip last week with a 5-6 hour between arrival & departure. When I got home my battery (according to the trickle charger, which I then plugged in), was still in the bottom quartile of charge. I have no idea what it takes for the drive batteries to impact the 12V but I would have thought that should have made more of a difference? Then again, what do I know? I am still a learner here!
That said, I have all manner of non-thread issues.
(BTW: your Forum joining-date was about the time I bought my Taycan - I can see you have been busy posting/participating since then!)
What type of trickle charger are you using?

It must support 12V LiFePO.
 

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Hi W1NGE (that plate must have cost you!),The charger does support 12V LiFePO - amongst others - although at those prices it should also provide me with a cooked meal & a cup of Earl Grey. It is the Porsche-badged one I bought from them after my first run-in with this flat 12V problem (solely because the car has whatever is left from the 4 year warranty & I did not want a dispute if I used a 3rd party one. If something went awry, I could see them blaming that & invalidating the warranty!).
 

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Right tube set 12v battery status. 14+ its charging 13 its charged. Charges every time the car wakes up. IF you keep the keys glose to the car 3 metres it does not go to sleep and can act as a parasitic drain. A biscuit tin is your friend. (for the keys) or switch off keyless access.
Hi Benachie, thanks for this - I assume, by "Right tube", you mean the r/h side of display actually behind the wheel)? (sorry - all very new to me). Certainly my local Porsche Centre does not know about this because they agreed with me, it could not be done! I switched off keyless entry because every time I went to freezer in the garage the car "woke" & started draining both the 12V AND the electronic key batteries. After 2 weeks, I had to replace the Li batteries in both keys.
 

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It is not you. There is something faulty with your car. It could be a faulty 12V battery. It could be a faulty charger. Particularly with the evidence you just posted, I think a visit to a Porsche workshop is required.

EDIT: Perhaps post on linked thread. It has good traction from some people in the know, like @ct14garage or @prj. they might have an opinion on what to look for.

https://taycanforum.com/forum/threads/12v-battery-convert-to-a-cheap-alternative.32716/
Thanks to you, ovonrein, also; these sound like a VERY good idea. The car is going back for work on another, more serious issue (different forum thread required - AND its concurrent, monthly valet - got to have some perk for ALL the grief!) soon. Living in the "sticks", I had to wait for a courtesy car to become available :( . Think I saw this thread the other day & @ct14garage is the guy in Thailand. When I get a minute or two later, I will try that thread.
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