991.1 Battery Replacement DIY
10-16-2020, 09:33 AM
#347
Racer
I just replaced my original 8 year old battery two days ago. Found a 48 month Champion AGM H8 900 CCA at Pep Boys. They have gone to a new structure on pricing and gave me 25% off for a total of $153.00. This battery is made by Johnson Controls, as most are. I had no problem changing it (thanks to the gents that have posted DIY's here and on you tube) and didn't lose a thing but the time. I noticed yesterday that the clock reset itself. I am a purest but not drinking the cool aid on the need for a "oem" Porsche battery. we'll see how it performs and lasts...
Last edited by jimmiejam; 10-17-2020 at 04:10 PM.
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Porsche_nuts (10-16-2020)
10-28-2020, 06:39 PM
#348
Rennlist Member
I just replaced my original 8 year old battery two days ago. Found a 48 month Champion AGM H8 900 CCA at Pep Boys. They have gone to a new structure on pricing and gave me 25% off for a total of $153.00. This battery is made by Johnson Controls, as most are. I had no problem changing it (thanks to the gents that have posted DIY's here and on you tube) and didn't lose a thing but the time. I noticed yesterday that the clock reset itself. I am a purest but not drinking the cool aid on the need for a "oem" Porsche battery. we'll see how it performs and lasts...
thanks to this thread, was a super easy swap and took 30min total including gather the tools
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jimmiejam (10-28-2020)
10-29-2020, 01:37 PM
#349
DIY Battery change
You should get someone to register the new battery with your car computer. I had mine done at Porsche when I went in for the heat shield recall. The computer changes the start-stop and other features I believe based on the ampacity of the battery. By moving to the 8H these criteria will change. A diagnostic tool such as the POR V2.0
can do this or get it done next time you go to a shop. I think it's fine to drive until you can have it done only takes 5 min to do.
10-29-2020, 04:45 PM
#350
You should get someone to register the new battery with your car computer. I had mine done at Porsche when I went in for the heat shield recall. The computer changes the start-stop and other features I believe based on the ampacity of the battery. By moving to the 8H these criteria will change. A diagnostic tool such as the POR V2.0 https://www.amazon.ca/iCarsoft-Diagn.../dp/B07F2WF96Y can do this or get it done next time you go to a shop. I think it's fine to drive until you can have it done only takes 5 min to do.
10-29-2020, 05:29 PM
#351
Yes I changed mine and drove it for quite a while with no issues but if you change the size and especially the type why not have it registered with the computer? your Lithium battery is ok with the AGM charge rate and Antigravity has circuitry to prevent overcharging. Just don't understand why you wouldn't optimize your electrical system charging system for the battery you have in your car when Porsche puts the software in it to do that?
The reason I posted this is many are unaware that Porsche has such optimization software and in my Chevy truck I had back in 1977 it didn't matter except that it was 12 volt.
The reason I posted this is many are unaware that Porsche has such optimization software and in my Chevy truck I had back in 1977 it didn't matter except that it was 12 volt.
10-29-2020, 10:10 PM
#353
Successfully replaced original battery from my 2013 991.
- Original battery: > 7 years. Was still functioning. Idle mind is a devil's workshop. Itching to do something.
- Original battery : part# 999.611.070.10 / 12v 70Ah 760A EN /AGM
- Replaced with Interstate battery from COSTCO: MTX-49/H8 95Ah 900A. Yes, 10+ pounds more and bigger than the original.
- While swapping the battery, used "CTEK (56-959) Silver MUS 4.3 TEST & CHARGE" connected to 12v socket under glove compartment. I know, two schools of thought. But I didn't want any settings to be lost nor have issues with memory settings buttons (had issues with Cayenne). After the swap, it did retain all the settings. Car did beep/click when the old battery was disconnected, until the new battery was re-connected (it was strange)
- Used "iCarsoft Auto Diagnostic Scanner POR V2.0 for Porsche" to register/code the new battery. This worked for me, trick was to use Porsche battery part# 95861109221 , same specs as MTX-49/H8. In-addition, when entering, drop the first digit of the Interstate battery scanner code. I believe these are all from VARTA
New battery supposed to make any difference in driving experience? Seems a bit chirpy now or is it all in the head?
- Original battery: > 7 years. Was still functioning. Idle mind is a devil's workshop. Itching to do something.
- Original battery : part# 999.611.070.10 / 12v 70Ah 760A EN /AGM
- Replaced with Interstate battery from COSTCO: MTX-49/H8 95Ah 900A. Yes, 10+ pounds more and bigger than the original.
- While swapping the battery, used "CTEK (56-959) Silver MUS 4.3 TEST & CHARGE" connected to 12v socket under glove compartment. I know, two schools of thought. But I didn't want any settings to be lost nor have issues with memory settings buttons (had issues with Cayenne). After the swap, it did retain all the settings. Car did beep/click when the old battery was disconnected, until the new battery was re-connected (it was strange)
- Used "iCarsoft Auto Diagnostic Scanner POR V2.0 for Porsche" to register/code the new battery. This worked for me, trick was to use Porsche battery part# 95861109221 , same specs as MTX-49/H8. In-addition, when entering, drop the first digit of the Interstate battery scanner code. I believe these are all from VARTA
New battery supposed to make any difference in driving experience? Seems a bit chirpy now or is it all in the head?
I have been driving with the new battery. Some days and times, PICTURE-1 is the charging voltage (sport mode) for the newly ( MTX-49/H8 ) replaced battery and PICTURE-2 is the resting voltage(engine OFF, ignition ON). As indicated, I did register the battery as well.
Is this NORMAL? 15V?
I don't recall seeing 15V for my old/original battery
PICTURE-1
PICTURE-2
Last edited by 991howl; 10-29-2020 at 10:15 PM.
10-30-2020, 02:40 AM
#354
I also saw mine hit 15V on my new battery.
IMO, the programming can't hurt. Whether it's to right-size the charging for different-sized battery, or to modify charging algorithm for a new vs old battery. I'm not a battery engineer, but perhaps the higher 15V charge is due to the car thinking the old battery needs extra oomph to get charged up? And doing so on a healthy battery may overcook it, as AGM charging voltage according to my CTEK is 14.7V.
If I have access to iCarSoft, sure I'd be happy to get this done, but probably not worth buying an iCarSoft or paying dealership to eek out the extra year of life from battery.
IMO, the programming can't hurt. Whether it's to right-size the charging for different-sized battery, or to modify charging algorithm for a new vs old battery. I'm not a battery engineer, but perhaps the higher 15V charge is due to the car thinking the old battery needs extra oomph to get charged up? And doing so on a healthy battery may overcook it, as AGM charging voltage according to my CTEK is 14.7V.
If I have access to iCarSoft, sure I'd be happy to get this done, but probably not worth buying an iCarSoft or paying dealership to eek out the extra year of life from battery.
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Wrtflyr (10-30-2020)
10-30-2020, 06:59 AM
#355
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991howl, you're fine. Don't forget, it's getting colder out too, although your temps are not too low yet, but I don't really know the temps at which you started out.
10-30-2020, 12:49 PM
#356
Rennlist Member
oh what.... i had no idea the "vehicle info" screen had more beyond the 3 things (oil temp, oil press, water temp) LOL
10-30-2020, 01:21 PM
#357
Buying iCarsoft
I also saw mine hit 15V on my new battery.
IMO, the programming can't hurt. Whether it's to right-size the charging for different-sized battery, or to modify charging algorithm for a new vs old battery. I'm not a battery engineer, but perhaps the higher 15V charge is due to the car thinking the old battery needs extra oomph to get charged up? And doing so on a healthy battery may overcook it, as AGM charging voltage according to my CTEK is 14.7V.
If I have access to iCarSoft, sure I'd be happy to get this done, but probably not worth buying an iCarSoft or paying dealership to eek out the extra year of life from battery.
IMO, the programming can't hurt. Whether it's to right-size the charging for different-sized battery, or to modify charging algorithm for a new vs old battery. I'm not a battery engineer, but perhaps the higher 15V charge is due to the car thinking the old battery needs extra oomph to get charged up? And doing so on a healthy battery may overcook it, as AGM charging voltage according to my CTEK is 14.7V.
If I have access to iCarSoft, sure I'd be happy to get this done, but probably not worth buying an iCarSoft or paying dealership to eek out the extra year of life from battery.
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Class5Kayaker (11-04-2020)
10-30-2020, 01:28 PM
#358
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10-30-2020, 01:47 PM
#359
WAIT! WHAT? It's possible to adjust the volume level of the car's turn signals? How can I do that? I have a 2013 991.1 and often find I've left the blinker on for a bunch of miles because the click volume is so low. This has been the case with every Porsche I've ever owned - from my 1974 911 to my 2019 Cayenne, and everything else in between. So I figured it's just the way it is. If I can increase the volume, that would be awesome.
10-30-2020, 01:53 PM
#360
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WAIT! WHAT? It's possible to adjust the volume level of the car's turn signals? How can I do that? I have a 2013 991.1 and often find I've left the blinker on for a bunch of miles because the click volume is so low. This has been the case with every Porsche I've ever owned - from my 1974 911 to my 2019 Cayenne, and everything else in between. So I figured it's just the way it is. If I can increase the volume, that would be awesome.
https://rennlist.com/forums/991/1042...rn-signal.html
