Poll - 12v Battery Death and the Chargers They're Hooked Too

What home charger were you using when your 12 v battery died?


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beastbay

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Interesting hypothesis - is the 12v battery death problem due to home charger configurations for which Porsche didn't engineer? Or does the PMCC cause the problem just like other chargers?

Responses only from members who had a 12v failure please!
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MonkeysRock

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Guilty as charged, pun intended! We just had this happen a few nights ago. Plugged the car into a household garage outlet (we are currently staying in LA and renting a home here). The charger suggested 6 amps, so we went with that. Went to bed, in the morning there was an error reading. The car had barely been charged, from 45% to 47% and the cable was stuck in the car charging outlet. The car had locked itself, so we could not get inside. When we did manually open the door, the car would not start at all.

We had the service people come, jump-start the 12V battery and they just towed it away to the local Porsche dealership.

I will report back their findings.
 

daveo4EV

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if your charge rate was 6 amps - I believe porsche has now identified that as too low of an AC current and that will drain the 12V battery

that would make 2 known problems that we know for a fact will kill the 12V
  1. @louv original problem - which was fixed with the summer software update
  2. the 6 amp problem which porsche has now documented and is rumored to be fixed in a future update...
I believe there are other circumstances, but getting rid of two known cases that cause 12V faults is a great start - I hope Porsche keeps pushing and fixing issues.
 
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MonkeysRock

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if your charge rate was 6 amps - I believe porsche has now identified that as too low of an AC current and that will drain the 12V battery

that would make 2 known problems that we know for a fact will kill the 12V
  1. @louv original problem - which was fixed with the summer software update
  2. the 6 amp problem which porsche has now documented and is rumored to be fixed in a future update...
I believe there are other circumstances, but getting rid of two known cases that cause 12V faults is a great start - I hope Porsche keeps pushing and fixing issues.
Agreed. But Porsche should not “allow” us to use such a low rate by indicating this as soon as it detected it. Could have saved us all a big headache.
 

Vim Schrotnock

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I used the Porsche Mobile Charger Connect (PMCC) and my battery died twice. It was because the PMCC was 'looking' for a Porsche Home Energy Manager (PHEM) every 15 minutes and that was 'waking' the car up and led to the battery drain. That is the explanation my tech gave me. They reprogrammed the PMCC and I haven't had a problem since.

I do believe that was the issue, because after the reprogram, my car started charging immediately after I plugged in. Before the charging, it took almost a minute to begin charging - I guess because it was 'looking' for a PHEM.

Anyone with a PMCC should check with their dealer that they have the correct programming. I would also say that if your PMCC takes more than 10 seconds to begin charging after you plug it in, you have the wrong program.

Porsche should have caught this certainly, and I'm quite surprised they let this go and haven't issued some kind of service bulletin. I'll bet I'm not the only one with a PMCC that wasn't programmed correctly.:mad:
 


chrisk

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PMCC supports software updates from the home's wifi (mine is connected to my wifi) and you should not need the dealer to update it.
Once again, I am very negatively surprised by the lack of communication from Porsche and the fact they have not released the fixes yet.
 

MonkeysRock

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Agreed. But Porsche should not “allow” us to use such a low rate by indicating this as soon as it detected it. Could have saved us all a big headache.
As a follow up to my earlier post, the Porsche Mechanic at the dealer said he thought the 12v battery drained itself because our car was set to stop charging at 25%. This was not true. Our car was always set to stop charging at 85%. So, I am still baffled.

He also stated “If you are charging at home on 110 you need to change the current in the Porsche charger to 8 amps. It won’t charge on 6 amps. It is not strong enough.”

I think that is the real issue. We are now only charging at Electrify America for the time being.
 

chrisk

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He also stated “If you are charging at home on 110 you need to change the current in the Porsche charger to 8 amps. It won’t charge on 6 amps. It is not strong enough.”
PMCC is supposed to receive updates from your home wifi. Why doesn't Porsche push an update to PMCC to not allow less than 8amps? Hey Porsche, how hard is to do that?
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