981 battery life
Discussion
Has anyone had to replace the battery on their 981? At 4 years old mine is struggling to turn over despite being driven extensively everyday. Can I replace it myself or will anything like heated seats need reprogramming by an OPC?
Also I noticed the battery voltage on the on board computer is constantly at 15.1/15.2V, I don't know if this is relevant at all?
Oh well better effort than the MOLL batteries fitted to 9x7 which lasted about two years
Also I noticed the battery voltage on the on board computer is constantly at 15.1/15.2V, I don't know if this is relevant at all?
Oh well better effort than the MOLL batteries fitted to 9x7 which lasted about two years
Edited by SkinnyPete on Tuesday 19th December 21:09
Huskyman said:
If you have a multimeter check the battery voltage with the ignition off and it should be around 12.9 v DC, any lower and the battery might be rubber ducked. 15 v DC sounds a little high and my Boxster only boosted the voltage up to 14.8v DC with sports plus switched on
I don't I'm afraid, I have plugged my CTEK in overnight which is not something I ever bother to do, I'm hoping it will revive it a little.Maxym said:
The battery will need to be coded to the car. Looks like an (expensive) one from an OPC.
Do you have a source for that? Reason I ask is people said the same about the 9x7 but I never had any issues changing the battery myself except for the fact that it recorded in the cars ECU a hidden fault code - I only know this because the technician commented on it when the car was next serviced.One of my worries when extending my warranty for years 4 & 5 was that the battery may give up and I have to have a Poorsche one to keep the warranty valid.
If I don't drive my 2014 981 for 4-5 days the screen sometimes gives me a warning about voltage. Always starts first time mind you.
Just investing in a CTEX MXS 5.0 to help maintain its life for as long as possible.
If I don't drive my 2014 981 for 4-5 days the screen sometimes gives me a warning about voltage. Always starts first time mind you.
Just investing in a CTEX MXS 5.0 to help maintain its life for as long as possible.
If the battery is an AGM and has a QR code on the top, then yes it needs coding to the Gateway. The code underneath is a 15 digit code with a space at character 4. So everything 991/981 onwards.
People say it doesn't need coding but it does. Yes you can replace and it'll work fine but it won't last as long as one that's coded properly.
The Gateway needs to know it's a new battery in order to calculate ageing, charge strategies, charge level, condition, etc etc.
Charge voltage can be anywhere from 12.0-16.0v and be considered normal, battery management is different now than it was in 997.1 and previous. 997.2 had early battery management but still on lead acid.
But with regards to the OP, yes they last longer than the lead acids did, about twice the life, but once they deteriorate there's no bringing them back. Time for a new AGM.
PS:- You're trickle charging on the wiper bracket post yes? And not directly on the negative terminal.
People say it doesn't need coding but it does. Yes you can replace and it'll work fine but it won't last as long as one that's coded properly.
The Gateway needs to know it's a new battery in order to calculate ageing, charge strategies, charge level, condition, etc etc.
Charge voltage can be anywhere from 12.0-16.0v and be considered normal, battery management is different now than it was in 997.1 and previous. 997.2 had early battery management but still on lead acid.
But with regards to the OP, yes they last longer than the lead acids did, about twice the life, but once they deteriorate there's no bringing them back. Time for a new AGM.
PS:- You're trickle charging on the wiper bracket post yes? And not directly on the negative terminal.
TrackNutz said:
Oh dear.
I admit I was wrong :-) never had to change one in a newer modelAlthough a like for like battery swap would makes no odds imo.
The charger in the cars only needs to know ah and lead acid type, it seems.
So you are not really coding the battery as such, that’s still a dumb unit.
You are just telling the charger the battery type with a code, I see you can set type and ah rate manual though.
Thanks though , every day is a learning day. :-)
TrackNutz said:
Yes mate. Just telling the Gateway its capacity (Ah), battery type (AGM, lead acid, lithium, etc) and part no/serial.
But like you say, if you swap the battery it'll work fine, just won't last as long, as AGM batteries age they need different charge stratagies.
I don't think that would happen, the charge stratagies are based on Lead acid type so a different profile for AGM over other types.But like you say, if you swap the battery it'll work fine, just won't last as long, as AGM batteries age they need different charge stratagies.
As most people run a Ctek which has a recon mode the cars charger will not change how it looks at a battery on age.
A AGM kept over 80% charge all the time for 4 years will prob be better than a AGM which has be let to drop to 20% every other week if not charged.
It will charge at a rate for the AH what ever the age and what it detects is the battery peak.
what effects life is discharge % let the AGM go below 60% and it will reduce life so a Ctek is a must have for long life, cycle life is key not age.
Porsche911R said:
I don't think that would happen, the charge stratagies are based on Lead acid type so a different profile for AGM over other types.
Not quite sure what you're getting at?I'm stating that different battery types have different charge stratagies, hence the coding is different.
Battery management shouldn't let an AGM deplete to a non recoverable point anyway, that's why there is a battery sensor on the negative terminal and T30 shutoffs in the MFB.
Using a CTEK is obviously the best option to maintain and the battery manager can see this charge rate and adds this the battery profile. Hence again why the coding is important and the charger being connected upstream of the battery terminal sensor is vital.
TrackNutz said:
Not quite sure what you're getting at?
I'm stating that different battery types have different charge stratagies, hence the coding is different.
Battery management shouldn't let an AGM deplete to a non recoverable point anyway, that's why there is a battery sensor on the negative terminal and T30 shutoffs in the MFB.
Using a CTEK is obviously the best option to maintain and the battery manager can see this charge rate and adds this the battery profile. Hence again why the coding is important and the charger being connected upstream of the battery terminal sensor is vital.
agree, but you said it's age related charging, I don't think it is, so a like for like battery swap would make no odds to battery life.I'm stating that different battery types have different charge stratagies, hence the coding is different.
Battery management shouldn't let an AGM deplete to a non recoverable point anyway, that's why there is a battery sensor on the negative terminal and T30 shutoffs in the MFB.
Using a CTEK is obviously the best option to maintain and the battery manager can see this charge rate and adds this the battery profile. Hence again why the coding is important and the charger being connected upstream of the battery terminal sensor is vital.
the systems charges on the condition of the battery and type, a battery kept at 80% might last 4 years longer than one which is not used and drops to 50%
TrackNutz said:
Not quite sure what you're getting at?
I'm stating that different battery types have different charge stratagies, hence the coding is different.
Battery management shouldn't let an AGM deplete to a non recoverable point anyway, that's why there is a battery sensor on the negative terminal and T30 shutoffs in the MFB.
Using a CTEK is obviously the best option to maintain and the battery manager can see this charge rate and adds this the battery profile. Hence again why the coding is important and the charger being connected upstream of the battery terminal sensor is vital.
That's intesting. Excuse dumb question but would a charger connected to the 12v lighter socket be "connected upstream of the battery terminal sensor"?I'm stating that different battery types have different charge stratagies, hence the coding is different.
Battery management shouldn't let an AGM deplete to a non recoverable point anyway, that's why there is a battery sensor on the negative terminal and T30 shutoffs in the MFB.
Using a CTEK is obviously the best option to maintain and the battery manager can see this charge rate and adds this the battery profile. Hence again why the coding is important and the charger being connected upstream of the battery terminal sensor is vital.
Hang On said:
That's intesting. Excuse dumb question but would a charger connected to the 12v lighter socket be "connected upstream of the battery terminal sensor"?
Yes that's fine. It's when you connect directly to the battery terminal that causes issues. Connecting to a plug socket can be unreliable at times however, sometimes the battery manager shuts off T30SD which cuts off the sockets from the battery. Vehicle dependant obviously.
Porsche911R said:
agree, but you said it's age related charging, I don't think it is, so a like for like battery swap would make no odds to battery life.
the systems charges on the condition of the battery and type, a battery kept at 80% might last 4 years longer than one which is not used and drops to 50%
Ah I see what you're saying. I'll have to check my archive but I sure a battery below 12.5v in AGM terms is critical in causing damage so the longer it stays in that range adds age, and the more age on a battery causes the management to change the way it tries and recovers it. I'll check though. the systems charges on the condition of the battery and type, a battery kept at 80% might last 4 years longer than one which is not used and drops to 50%
TrackNutz said:
Ah I see what you're saying. I'll have to check my archive but I sure a battery below 12.5v in AGM terms is critical in causing damage so the longer it stays in that range adds age, and the more age on a battery causes the management to change the way it tries and recovers it. I'll check though.
great info on this page now cheers. I hate batteries and race RC and built an Electric bike for my dad, it's no fun batteries these days, I think I have about 6 chargers !!! although my newest does every type of battery now.in my VW I use VCDS and you can see the AH and every thing in the car and change it, in a Porker durametric I don't think it lets you change it :-(
hence be good to know if it's age related as then people can just swap a like for like no issue.
If we are stuck with an OPC visit for a battery that's getting daft :-(
Having a trickle charger connected whenever the car is not in use for several days is no doubt beneficial. I have never bought a new battery for a Porsche in 30 years ! My last 2 vehicles were sold at 9 year old (996 Turbo) and 8 year old (987 Spyder) and both were on their original factory batteries ! Charger connected whenever cars were not used for more than 3 or 4 days.
A related question, I have been using a Porsche branded charger of 2004 vintage but am getting a new 718 GTS in January. Would you advise getting one of the new - more sophisticated - chargers such as a CTEK or Porsche branded ?
A related question, I have been using a Porsche branded charger of 2004 vintage but am getting a new 718 GTS in January. Would you advise getting one of the new - more sophisticated - chargers such as a CTEK or Porsche branded ?
TrackNutz said:
If the battery is an AGM and has a QR code on the top, then yes it needs coding to the Gateway. The code underneath is a 15 digit code with a space at character 4. So everything 991/981 onwards.
People say it doesn't need coding but it does. Yes you can replace and it'll work fine but it won't last as long as one that's coded properly.
The Gateway needs to know it's a new battery in order to calculate ageing, charge strategies, charge level, condition, etc etc.
Charge voltage can be anywhere from 12.0-16.0v and be considered normal, battery management is different now than it was in 997.1 and previous. 997.2 had early battery management but still on lead acid.
But with regards to the OP, yes they last longer than the lead acids did, about twice the life, but once they deteriorate there's no bringing them back. Time for a new AGM.
PS:- You're trickle charging on the wiper bracket post yes? And not directly on the negative terminal.
Interested in the comment above about not connecting charger directly to negative terminal. Ctek instructions say connect direct to battery terminals. What’s the issue with doing this on a 991.2 ?People say it doesn't need coding but it does. Yes you can replace and it'll work fine but it won't last as long as one that's coded properly.
The Gateway needs to know it's a new battery in order to calculate ageing, charge strategies, charge level, condition, etc etc.
Charge voltage can be anywhere from 12.0-16.0v and be considered normal, battery management is different now than it was in 997.1 and previous. 997.2 had early battery management but still on lead acid.
But with regards to the OP, yes they last longer than the lead acids did, about twice the life, but once they deteriorate there's no bringing them back. Time for a new AGM.
PS:- You're trickle charging on the wiper bracket post yes? And not directly on the negative terminal.
Thanks
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