Dead 12 volt battery this morning.

[JimBob]

Dead 12 volt battery this morning. Never had a problem before.

But I know what caused it. The car was plugged in and charged properly this morning. The car looked ok. I started playing around with the different service options in the MY Porsche App with the car plugged in. The first I tried was the E-Mobility option. And just got the little spinning wheel for most of them and the service could not connect with the car. Then played around with the the other services and had no problems. An hour later the 12 volt battery was dead.

That'll be the last time I try that.

RECOMENDATION. DO NOT TRY AND CHANGE THE SETTINGS IN THE CAR FROM ANYHWHERE OTHER THAN THE PCM.

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[AMERCY]

Dead 12 volt battery this morning. Never had a problem before.

But I know what caused it. The car was plugged in and charged properly this morning. The car looked ok. I started playing around with the different service options in the MY Porsche App with the car plugged in. The first I tried was the E-Mobility option. And just got the little spinning wheel for most of them and the service could not connect with the car. Then played around with the the other services and had no problems. An hour later the 12 volt battery was dead.

That'll be the last time I try that.

RECOMENDATION. DO NOT TRY AND CHANGE THE SETTINGS IN THE CAR FROM ANYHWHERE OTHER THAN THE PCM.

Sorry for that. Yet: Was it MY'20 or MY'21? Jour joined-day might suggest already that it might be a MY'21.
Being curious, as my MY'21 S4+ is being intensly accessed thru app and web, without issues. Fingers crossed,

 

[JimBob]

Sorry for that. Yet: Was it MY'20 or MY'21? Jour joined-day might suggest already that it might be a MY'21.
Being curious, as my MY'21 S4+ is being intensly accessed thru app and web, without issues. Fingers crossed,

MY2020

 

[JimBob]

For those interested.

This is like a hot stove, I know I'm not supposed to touch it, but am going to do it anyways.

A nice chap from Porsche Roadside Assistance showed up within 40 minutes and got the car going. He hadn't jumped a Taycan before but had a general idea as to how to do it. He used one of the NOCO type boosters. I had the cheat sheets previously posted on this forum which proved useful for him to refer to. Funny thing was his next call was another dead Taycan, so now he knew what to do.

I wasn't going to do it, because it was cold outside and Porsche can pay for it.

Took two tries before the dash lit up and stayed lit up.

The two big problems were that the car said there was a problem with the electronic brake. After a little fussing about, pressing the brake and holding it, the car reported the brake and the problem was solved. The harder problem was getting the plastic liner in the frunk back in place.

Tomorrow I am going to try the MyPorsche App, but one function at a time, to see if I can find which one caused the problem. And then call Porsche Roadside Back.

One good thing was that when I told the wife about it, she said why did you buy that car? Can you get your old car back? I hate technology. Now I don't have to get that Macan as she'll keep her old Lexus. Saved a $100,000.

 

[chrisk]

One good thing was that when I told the wife about it, she said why did you buy that car? Can you get your old car back? I hate technology. Now I don't have to get that Macan as she'll keep her old Lexus. Saved a $100,000.

The Macan's technology is actually outdated, nothing even close to Taycan, so she will be fine with a Macan.

 

[JimBob]

The Macan's technology is actually outdated, nothing even close to Taycan, so she will be fine with a Macan.

But she doesn't know that.

 

[JimBob]

I attempted to duplicate what I thought caused the problem. Went into MyPorsche, should be similar to the Porsche Connect App.

It worked just fine. Tried all kinds of combinations and everything worked ok.

So this is all I think I know
1. The dead 12v could happen anytime
2. I have not heard of instances where the problem occurred while driving
3. As far as I know, it happens when the car is parked and plugged in or charging
4. Zero confidence that it won't happen stranding you in the middle of nowhere
5. There appear to be two cases of 12v battery problems
(i) the battery gets isolated and power needs to be applied to wake the car up
(ii) seems to be less frequent, but the 12v battery actually loses charge and needs to be recharged
6. In my case when the car was jumped the 12v battery showed it was still charged at 13.7v, so the
battery had become isolated from the car
7. This has been going on for awhile with no fix. Maybe when Porsche gets tired of paying the towing bills and coast of Roadside Service they will fix it

 

[chrisk]

2. I have not heard of instances where the problem occurred while driving
3. As far as I know, it happens when the car is parked and plugged in or charging

2. There was an instance of someone in UK that the car died while driving and it was completely dead and the PA person told him the 12v battery was dead. The owner returned the car. There are a few reports (even NHTSA complaints) of cars stalling while driving. It can be a bad converter, or something else but we cannot rule out a connection to the 12v issue.

3. There was a report of someone from Northern Europe that his car died while parked unplugged. He first had the issue a few weeks prior to that while the car was plugged, so maybe his battery got in a bad state after the first occurrence.

 

[daveo4EV]

yeah it's a non-reproducible problem - it can strike any time when the vehicle is engaged in AC charging - I've not heard a single report during DC fast charging.

and I've not heard of anyone's car dying while it was unplugged

my theory is the charging software can get confused during the charging session and once it gets confused it drains the 12V battery - I've had one actual "death" and I caught it in the act...the one I caught in the act was draining the 12V while I captured data of the Taycan's charging software losing it's mind and starting and stopping the charging session over and over and over and over…

I captured this data and provided it to Porsche - I'm monitoring the access to this data via google doc's access logs - and my data set has been accessed during business hours almost continuously for the past (2??) weeks - and only a few people have the access codes to see the data...so I think Porsche is consulting my data to try and figure out what's happening…

we'll see.

there is some random chance the Taycan's charging software can get confused and if it does it will loop and kill the 12V battery - what triggers this loop is unknown, but I'm sure making changes to charging parameters while charging does not help the situation, but alone is insufficient to tigger the loop…

you can not 100% avoid the loop, but doing certain things increase the odds it will happen…like messing with charging via the app…but cold turkey doesn't change the odds to zero - just less frequent.

 

[John89]

My car was dead this morning. At dealership now

 

[Doc B]

yeah it's a non-reproducible problem - it can strike any time when the vehicle is engaged in AC charging - I've not heard a single report during DC fast charging.

and I've not heard of anyone's car dying while it was unplugged

my theory is the charging software can get confused during the charging session and once it gets confused it drains the 12V battery - I've had one actual "death" and I caught it in the act...the one I caught in the act was draining the 12V while I captured data of the Taycan's charging software losing it's mind and starting and stopping the charging session over and over and over and over…

I captured this data and provided it to Porsche - I'm monitoring the access to this data via google doc's access logs - and my data set has been accessed during business hours almost continuously for the past (2??) weeks - and only a few people have the access codes to see the data...so I think Porsche is consulting my data to try and figure out what's happening…

we'll see.

there is some random chance the Taycan's charging software can get confused and if it does it will loop and kill the 12V battery - what triggers this loop is unknown, but I'm sure making changes to charging parameters while charging does not help the situation, but alone is insufficient to tigger the loop…

you can not 100% avoid the loop, but doing certain things increase the odds it will happen…like messing with charging via the app…but cold turkey doesn't change the odds to zero - just less frequent.

Just to throw oil on the fire, this has happened to cars (at least two I've heard of) while unplugged:

https://www.taycanforum.com/forum/threads/car-died-over-night….2525/page-10#post-54609

 

[caytan]

My car was dead this morning. At dealership now

Software in this car is a complete dumpster fire. Both software for outside services and software in the car itself.

I am suspecting this will never get fixed properly and our cars will be part of the legacy software once they write new software on new hardware. That's why I leased.

 

[kort]

Software in this car is a complete dumpster fire. Both software for outside services and software in the car itself.

I am suspecting this will never get fixed properly and our cars will be part of the legacy software once they write new software on new hardware. That's why I leased.

that certainly is a big reason to lease this car. another big reason is that in the EV world the technology evolves quickly and with all the new players getting into the EV game the today's state of the are car could become functionally obsolete quickly.
this happened to me and all the early tesla model S buyers when in 2015 tesla introduced both an AWD model S and AP1 which rendered all the earlier teslas functionally obsolete.

 

[NC_Taycan]

this happened to me and all the early tesla model S buyers when in 2015 tesla introduced both an AWD model S and AP1 which rendered all the earlier teslas functionally obsolete.

Actually it turned out the lack of Autopilot hardware was a reason my Model S buyer wanted my 2012 car...

 

[John89]

that certainly is a big reason to lease this car. another big reason is that in the EV world the technology evolves quickly and with all the new players getting into the EV game the today's state of the are car could become functionally obsolete quickly.
this happened to me and all the early tesla model S buyers when in 2015 tesla introduced both an AWD model S and AP1 which rendered all the earlier teslas functionally obsolete.

[QU

Car still at dealership. They claim that the battery is fine but they are waiting to see whats up after charging it overnight.

Update: Car back. They say battery was fine, was just dead and they charged it. They also changed some settings in my charger that is supposed to help this not happen. Claim that the huge software update that is coming will allegedly address this and many other issues. We shall see

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