New battery?
#18
Instructor
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You're right it doesn't, but like I said there were other signs and data points that led me to the conclusion I did. The fact that it cranked slow after not being driven and then was somewhat better after driving it for a while, plus the PCM wigging out plus a 10 year old battery ...well..all signs point to the battery.
#19
Rennlist Member
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#20
Instructor
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In your case, yes but in the case of the 997, it would start when the engine was at ambient temperature (first drive of the day), but would hardly turn over once the engine was warm on re-starts. A lesson RLers might keep in mind should they come across that scenario. Of course our 991s are newer, but as they age...
What you're describing sounds like you were crossing your fingers that the car would actually start when it cranked slow? If that's the case then yeah, that's not what I experienced. And actually in my case the restarts improved the cranking speed...just not to the same level I'm experiencing now...which is normal for fully functioning battery.
#21
Three Wheelin'
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These cars are so finicky about voltage levels, it doesn’t seem to take much from the battery being all “it’s 5+ years old, the original, doing great!” To yet another “weird error message and dash lights are on, what’s wrong?”-post. One day fine, next day stranded without warning. YMMV of course, but why risk it?
#22
Racer
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These cars are so finicky about voltage levels, it doesn’t seem to take much from the battery being all “it’s 5+ years old, the original, doing great!” To yet another “weird error message and dash lights are on, what’s wrong?”-post. One day fine, next day stranded without warning. YMMV of course, but why risk it?
#24
Rennlist Member
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After 5.5 years the original battery in my 2017 started showing signs (a few unprovoked error messages, like for bad L and R tail lights, and auto stop/start not kicking in). I replaced it with a Antigravity H6 Group 48. It has worked perfectly so far.
#25
Rennlist Member
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Don't replacement batteries now have to be registered with the car's ECM?
I know BMW/MINI have a computer-controlled alternator that requires such. And I think I saw somewhere the same for Porsche.
I know BMW/MINI have a computer-controlled alternator that requires such. And I think I saw somewhere the same for Porsche.
#26
Rennlist Member
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I might be wrong, but I can see it only needing the Ah rating of the battery and the battery type (FLA, EFB, AGM, GEL, etc). The serial number and manufacturer of the battery is probably unimportant. I doubt very much the ECU will have a list of endless battery manufacurers and serial numbers.
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JHW911 (02-05-2023)
#29
Drifting
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I just replaced my OEM battery on my 2015 GTS. It still started fine and tested OK, but I was getting concerned it might strand me somewhere, but it was 8 years old and still strong. These AGM batteries last longer.
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IXLR8 (01-31-2023)
#30
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Just replaced my battery on my '15 GTS as well. It completely died (wouldn't even jumpstart and the trickle charger refused to charge it). Swapped to a lithium anti-gravity battery and it's MUCH better. Not only is the lithium battery way lighter it also has jump starting built in. Was really simple to do at home. Just need some metric socket wrenches (ideally with an extender) and some ratcheting wrenches and a torx screwdriver. These batteries used to have some gotchas but they're all ironed out now. Plug and play.
The main thing is after replacing the battery if it was completely dead you'll have to deal with some warning lights and oddities for the first few drives. For example, I got a warning about the steering range. Just had to move the steering wheel back and forth to both extremes and restart then repeat and it went away. Also had to reset windows and PDK initially went into limp mode so had to warm the car up then do a PDK relearn. I think I only had to do all this b/c the old battery was completely fried. If your battery isn't dead yet I recommend keeping the car on a tender to avoid having to deal with this stuff (not a big deal but easier for sure).
You do not need to specially code the car to have a new battery. I believe it does reduce the charging speed if you don't code it but not a big deal. Also, if using a lithium battery remember to only use a lithium trickle charger.
The main thing is after replacing the battery if it was completely dead you'll have to deal with some warning lights and oddities for the first few drives. For example, I got a warning about the steering range. Just had to move the steering wheel back and forth to both extremes and restart then repeat and it went away. Also had to reset windows and PDK initially went into limp mode so had to warm the car up then do a PDK relearn. I think I only had to do all this b/c the old battery was completely fried. If your battery isn't dead yet I recommend keeping the car on a tender to avoid having to deal with this stuff (not a big deal but easier for sure).
You do not need to specially code the car to have a new battery. I believe it does reduce the charging speed if you don't code it but not a big deal. Also, if using a lithium battery remember to only use a lithium trickle charger.