key fob dead AGAIN
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From: Moose Mtn. Alaska
I would dare say it would also have an impact on the car's battery. Yet another piece of code to replace in the BMS "system".
Why don't they just scrap the whole sorry excuse for a battery management system. Migrate to 48v and get someone who actually understands multi-threaded RT coding...
siberian
Why don't they just scrap the whole sorry excuse for a battery management system. Migrate to 48v and get someone who actually understands multi-threaded RT coding...
siberian
Last edited by siberian; Mar 5, 2023 at 07:39 PM.
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Hi Siberian - I think you've got something there with allowing the battery to discharge naturally and not place on a charger daily. That's actually what I'm doing now after putting the car on the charger every day (CTEK charger direct to battery since cigarette lighter option's a fail by Porsche). When putting the charger on every day I noticed that while driving the voltage would stay around 12.1 or 12.2 probably because the car sensed that it didn't need to charge the battery since it was always coming off the charger before driving. My battery tracker would show the battery power going down and down and for some reason the car still would not charge (voltage stayed at 12.1 or 12.2). Now, by not charging every day I noticed that the voltage stays around 13.1 or 13.2 sometimes going as high as 14.8 at times. Very odd.
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I should have mentioned in my garage (external 6 car garage) - I have a custom Faraday full key locker that I can store around 10 - 12 keys in. Mine go there after each drive.. Still the same 3-4 months for the porsche.
On my 991.2 GT3 Touring - I leave the keys in the car, no issue after 3-4 year. McLaren 720s - no issue. My wife Audi RS Q8 (after 1 year) no issue). I can go down the list of 11 or so cars I have - no issues at all. The 992 - big problem, when it comes to key fob battery life.
Siberian - I think you are also correct - that is not a one way communications - it would also sap car battery life as well (even though much larger, Thought (unlike others) I have not had a problem with my LiPos on my 992s (both had RAS).
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From: Moose Mtn. Alaska
Yes, it's definitely not a one way communication and it will wear the AGM or LIFEPO4 when added to all the other gremlins that feed on them.
@satk What you mention supports my previous post(s). I tend to let my LiFePO4 sit for 3 days and then place on charger. The 992 is in a detached (single car alas @Richard_Wallace
) abode so nowhere near the FOB. The Macan S is of course in it's Faraday pouch since it's in the same building as the house. For the record my 08 V8 Touareg also doesn't have a problem, nor does it need to be driven x miles a year...oh I forgot it's a VW and back in 2008 we didn't have these issues or improvements...
siberian
@satk What you mention supports my previous post(s). I tend to let my LiFePO4 sit for 3 days and then place on charger. The 992 is in a detached (single car alas @Richard_Wallace
) abode so nowhere near the FOB. The Macan S is of course in it's Faraday pouch since it's in the same building as the house. For the record my 08 V8 Touareg also doesn't have a problem, nor does it need to be driven x miles a year...oh I forgot it's a VW and back in 2008 we didn't have these issues or improvements...siberian
Last edited by siberian; Mar 5, 2023 at 08:50 PM.
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Hi Siberian - I think you've got something there with allowing the battery to discharge naturally and not place on a charger daily. That's actually what I'm doing now after putting the car on the charger every day (CTEK charger direct to battery since cigarette lighter option's a fail by Porsche). When putting the charger on every day I noticed that while driving the voltage would stay around 12.1 or 12.2 probably because the car sensed that it didn't need to charge the battery since it was always coming off the charger before driving. My battery tracker would show the battery power going down and down and for some reason the car still would not charge (voltage stayed at 12.1 or 12.2). Now, by not charging every day I noticed that the voltage stays around 13.1 or 13.2 sometimes going as high as 14.8 at times. Very odd.
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That's not odd at all - its your alternator running. When the system senses the battery needs charging, it clutches the alternator into play, otherwise its not engaged to save on gasoline.
Are you sure that Faraday box works? Put your cell phone in there and call it - does it ring?
Are you sure that Faraday box works? Put your cell phone in there and call it - does it ring?
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From: Moose Mtn. Alaska
I just have no faith or trust in the entire BMS and at the price of a LiFePO4 battery ... whether it's your phone or other it's not good to leave your items plugged in 24/day. YMMV
siberian
siberian
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Here's more to add to the paranoia. Whenever I park the car and won't drive it for more than 2 days I raise the frunk just in case the battery craps out in the 3 day max time frame between CTEKs. Meaning 3 days not driven = not charged, on the 4th day it goes on the charger for 3 days or is driven whichever is sooner.
This on a $170k+ car... Can't wait to do the TSB upgrade in Spring that my dealer opines I don't need and PCNA couldn't care less.
siberian
This on a $170k+ car... Can't wait to do the TSB upgrade in Spring that my dealer opines I don't need and PCNA couldn't care less.
siberian
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Hi Siberian - fortunately my dealer performed the TSB upgrade although it took a little persistence. Interesting that they did not make it known it was out there. I only found out about it through you and went to them with the bulletin you attached to your post. I'll let you know if it helps. I'm more or less following what you are doing with putting it on the CTEK only after a few days. Good idea about opening the frunk just in case!
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Originally Posted by siberian;[url=tel:18672548
18672548[/url]]Here's more to add to the paranoia. Whenever I park the car and won't drive it for more than 2 days I raise the frunk just in case the battery craps out in the 3 day max time frame between CTEKs. Meaning 3 days not driven = not charged, on the 4th day it goes on the charger for 3 days or is driven whichever is sooner.
This on a $170k+ car... Can't wait to do the TSB upgrade in Spring that my dealer opines I don't need and PCNA couldn't care less.
siberian
This on a $170k+ car... Can't wait to do the TSB upgrade in Spring that my dealer opines I don't need and PCNA couldn't care less.
siberian
In the old days, there would be a battery cutoff switch.
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From: Moose Mtn. Alaska
In the old days like my 2008 V8 Touareg I don't have an issue, it can sit for weeks on a wet cell battery with no BMS etc. Options? Unless there's a dollar figure attached to it, I wouldn't dream of it.
siberian
siberian
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From: Moose Mtn. Alaska
Hi Siberian - fortunately my dealer performed the TSB upgrade although it took a little persistence. Interesting that they did not make it known it was out there. I only found out about it through you and went to them with the bulletin you attached to your post. I'll let you know if it helps. I'm more or less following what you are doing with putting it on the CTEK only after a few days. Good idea about opening the frunk just in case!
siberian
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If you press lock and unlock button simultaneously on your fob, hold for 3-5 seconds, Porsche crest lights solid, key is now asleep. No searching. You can leave it on the car, next to the car. Movement will not wake it. Press any button on the fob and it reactivates. Good to go.
