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Official Porsche documented guidance for the 12v battery

ZenicaNC

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Is there a Porsche official document for guidance related to the 12v battery? How it should be maintained or treated in abnormal conditions?
Such as longer than 3 months storage without an electrical source, disconnection from the HVB system or any other scenario where it cannot
benefit from the HVB?
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Genau

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ZenicaNC

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These are helpful but don’t outline a specific procedure or process. Neither document actually has language advising not to disconnect or guidance on how long to leave the 12v battery disconnected if doing so is necessary.
I’m trying to see if the dealer is taking steps to protect the 12v battery and not reduce its viability by leaving it disconnected
 

hrtlik

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It is just 12V a lifepo battery with BMS as any other. Porsche has not resolved issues with battery drain so I would not rely on any of their advice.

Put it on any LFP trickle smart charger in case of longer stay than few days. My 12V died twice - first it died completely after winter stay with AC charger connected and had to be towed. Second time was week ago after 14 days of staying in a garage. Since then I decided to carry on in a frunk AGM 40ah battery to jump start it and small cheap booster to open frunk. I have not been sucessful to start Taycan with 10000mah booster alone.

It is shameful but it explains why their sales been dropping every quarter now.
 

prj

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It is just 12V a lifepo battery with BMS as any other. Porsche has not resolved issues with battery drain so I would not rely on any of their advice.

Put it on any LFP trickle smart charger in case of longer stay than few days. My 12V died twice - first it died completely after winter stay with AC charger connected and had to be towed. Second time was week ago after 14 days of staying in a garage. Since then I decided to carry on in a frunk AGM 40ah battery to jump start it and small cheap booster to open frunk. I have not been sucessful to start Taycan with 10000mah booster alone.

It is shameful but it explains why their sales been dropping every quarter now.
There was a 12V recall early this year for all the cars that solved the issue. There was a problem with the sensor in the battery reporting the incorrect values on some cars resulting in the SoC of the 12V battery being incorrectly calculated (and then not topped up and dying).

It also affected only some cars. E.g. I never had a single issue on my Turbo S and I left it for 8 weeks in the summer - it fired up right off the bat when I got back, no problems.

Sounds like your car is affected - in that case get the recall done.
 


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These are helpful but don’t outline a specific procedure or process. Neither document actually has language advising not to disconnect or guidance on how long to leave the 12v battery disconnected if doing so is necessary.
I’m trying to see if the dealer is taking steps to protect the 12v battery and not reduce its viability by leaving it disconnected
You don't need to do anything unless you're leaving it for a very, very long time.
 

targa666

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There was a 12V recall early this year for all the cars that solved the issue. There was a problem with the sensor in the battery reporting the incorrect values on some cars resulting in the SoC of the 12V battery being incorrectly calculated (and then not topped up and dying).
I am still searching where to find the SOC of the 12V battery!
 

PorscheTaycan

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I am still searching where to find the SOC of the 12V battery!
On the dash screen, it's on the right hand side section where you can see the battery SOC, and other car info, you can also see the 12V SOC.

See below image (found off Google search, not my car):

Porsche Taycan Official Porsche documented guidance for the 12v battery 1776405940131-u6
 


targa666

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lol. I actually saw that one a few days ago but didn’t connect the dots!!
sooooo much info to digest…. Thanks!
 
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ZenicaNC

ZenicaNC

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I picked up my Taycan and it seems okay. They replaced 5 cells. Hopefully this doesn't become a pattern. The car is no longer under the CPO though I do have the Fidelity plan.
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