12V battery died

[EXOTIC3]

Car is bricked 20 turbo with only 20,000 miles zero power had to use manual key to unlock.

Thanks in advance

Can I recharge a 12 V battery? I’m not sure what happened.

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[MrJones02]

Yes, in most cases you just need to re-charge your 12v and everything is back to normal again.

search the forum for the procedure to get the frunk open, or get roadside assistance to do it ... probably wont be the first Taycan they need to revive so they know how to do it.

 

[whitex]

Car is bricked 20 turbo with only 20,000 miles zero power had to use manual key to unlock.

I may be 20k miles but it's up to 7 years old by now. Batteries age, they need replacement. You can jump-start and try charging it up again. Make sure you are up to date with all the recalls too, as 2020 was the first model year known for 12V battery charging bugs.

 

[JenniATL]

Is this something we need to worry about? Does the car not give any warning?

 

[SoccerMan94043]

Is this something we need to worry about? Does the car not give any warning?

All the Taycan's have an update to help with this (not sure about 2026, since it may have come with it already). I don't think I've heard anyone get an alert yet though.

 

[MrJones02]

When it happened to me, I didn't see a warning ... well the car had been sitting for 2 weeks and in low temperature.
When it was revived, it did show "low battery" ... I'm like duh, now you tell me.

Well that was 8 months ago, has been fine since.

 

[EXOTIC3]

Thanks for all the requires fellas. I appreciate it. I was able to get that 12 V battery jumpstarted and was able to get charging of the big battery resumed things seem to be going well but I came out this morning and it was completely dead again. do you need to slow charge the 12 V battery first rather than just a quick jump?

 

[MrJones02]

Keep the car "on" for it to charge the 12v, or take it for a drive ... in the instrument-cluster, right tube, you can see the voltage of the 12v ... if it shows over 14v it means its still charging ... once it drops to aprox 13.5 it's fully charged.

 

[tycanmt]

Mine just got the 12V firmware update so I will try not turning it on for a couple weeks to see what happens..

 

[Dee]

I may be 20k miles but it's up to 7 years old by now. Batteries age, they need replacement.

Not true.
These batteries don't draw that much power like a battery for an ice.
High (cranking) power really puts stress on those 12V batteries and therefore life span.
Batteries on EV's last very long, at least 10 years or more (ask @ct14garage ).
Mine is over six years old and is in perfect condition, still a rock solid 13,4V.
Never ever experienced a dead 12V battery and my Taycan was one of the first in the country.

Problem is, if these batteries get below a certain voltage, they shut down and can't even be recharged cuz of the internal protection by software.
There are shops that can physically open up a battery a recondition them though.
If you can recharge the 12V battery by the recover procedure you're lucky cuz normally Porsche will replace the battery and that's a $1500 service, even if the battery could be saved but Porsche doesn't open them, of course.

 

[EXOTIC3]

Thanks much again for the responses this morning. Tow truck is coming to pick up the car at the moment. I can’t even get it into park as it’s completely dead again and level two is plugged in. I did reach out to my service advisor over this as my car is still under CPO he said the 12 V battery is not covered and cost of the battery and programming is north of $2500… I’m sorry that’s just ridiculous.

 

[TonyR]

There was a problem with batteries going dead due to faulty monitoring but there is a software update to solve that so the HV battery keeps it topped up. The battery doesn't actually go flat. It gets disconnected when the voltage drops to prevent it going flat. The boost process through the fuse box simply reactivates it. But if you haven't had the update and haven't driven it to recharge it it will switch off again pretty quickly. If you want to recharge it at home make sure you have a charger for a Lithium battery, not a standard lead acid car battery one.

 

[tycanmt]

Not true.
These batteries don't draw that much power like a battery for an ice.
High (cranking) power really puts stress on those 12V batteries and therefore life span.
Batteries on EV's last very long, at least 10 years or more (ask @ct14garage ).
Mine is over six years old and is in perfect condition, still a rock solid 13,4V.

Also the battery chemistry is totally different. Lithium batteries last (should last) much longer than lead acid.

 

[EXOTIC3]

There was a problem with batteries going dead due to faulty monitoring but there is a software update to solve that so the HV battery keeps it topped up. The battery doesn't actually go flat. It gets disconnected when the voltage drops to prevent it going flat. The boost process through the fuse box simply reactivates it. But if you haven't had the update and haven't driven it to recharge it it will switch off again pretty quickly. If you want to recharge it at home make sure you have a charger for a Lithium battery, not a standard lead acid car battery one.

thanks yeah when I first had help with the 12 V battery we just used direct jumper cables for like 10 seconds to wake it up ……obviously that’s a no no needs to be a jump box. Understood that now. Second time we did use the jump box but as reported I was able to get flashing green light to start charging and my locks trunk , etc. all worked on the remote, but once the charging cycle is over, it was completely dead again. I also turned the car off. Right after waking up 12V……..Perhaps I should’ve left it on when we started level two charging.

 

[TonyR]

Second time we did use the jump box but as reported I was able to get flashing green light to start charging and my locks trunk , etc. all worked on the remote, but once the charging cycle is over, it was completely dead again. I also turned the car off. Right after waking up 12V……..Perhaps I should’ve left it on when we started level two charging.

The jump leads are fine to tickle it awake. A jump box is designed to jump start a car not recharge the battery. Also get one with an override on sensing a battery. Many won't provide a jump until they sense a battery is present which they won't do if the battery is dead or disconnected.

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