981 battery life - Page 4 - Boxster/Cayman - PistonHeads UK

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 Edited by SkinnyPete on Tuesday 19th December 21:09

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

The battery will need to be coded to the car. Looks like an (expensive) one from an OPC.

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.

Interestingly enough I have not had any low voltage warnings, just the car was a bit limp wristed starting yesterday and today very limp wristed! Design 911 has the batteries for about £150, I wonder if I can replace my current 80AH with a 90AH version?

Maxym said: The battery will need to be coded to the car. Looks like an (expensive) one from an OPC. Not this again, there is nothing on a battery to code, I have changed loads.

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.

Porsche911R said: Not this again, there is nothing on a battery to code, I have changed loads. Oh dear.

TrackNutz said: Oh dear. I admit I was wrong :-) never had to change one in a newer model Although 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. :-)

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.

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. 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. 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"?

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.

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 ?

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 ? Thanks

WG said: 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 ? Yes, I'd highly recommend a new CTEK for your 718.

curious2 said: 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 ? Thanks The issue is that it bypasses the battery sensor. Have a look at the two pin connector on a small black block at the negative terminal. This is the sensor. The correct location is the wiper motor bracket. There is a small negative terminal symbol next to the bolt post on the bracket.

WG said: 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 ? Does your 2004 model look like a CTEK unit re-branded? I phoned my OPC yesterday and they offered a "Charge-o-mat at £94.99 which I believe is a re-branded CTEK 3.6 or 3.8. The general consensus seems to be to get the CTEK MXS 5.0. I need to run this from the rear of my garage, through the door, into the armrest 12v socket (which I think is the only one in my 2014 981 which knows if you're charging by it so doesn't switch off with a charger connected - at least that's what the OPC told me). I found the necessary items, including an extension cable, cheapest here: https://www.amazon.co.uk/dp/B01MZZ6T5F/_encoding=U... https://www.amazon.co.uk/dp/B00ADIHUVG/_encoding=U... My OPC says it's fine to run the cable through the door as the door seals will give and not damage it. The 5.0 manual has a flow chart of the different "modes"... ...and then describes them... NB: Manual here: https://www.ctek.com/storage/ma/b343d2275859476796... So, for my 3 1/2 year old battery, I guess I just plug the charger in and it gets to work BUT I have to select some options... Which do I choose, AGM or RECOND? There's further detail in the manual... Without guessing what battery type, I guess I need to check the battery itself which will tell me which of these programs to use? Is that correct? Thanks for any help.

^ You want AGM and Normal; the two middle lights. The unit will default to that selection when your turn it on. Your OPC is correct about the cable going through the bottom door seal. If you open the window with the cable thus trapped you will find you can reach down, grab it and it will slide side-to-side with minimal pressure so no damage being done.

Hang On said: ^ You want AGM and Normal; the two middle lights. The unit will default to that selection when your turn it on. Your OPC is correct about the cable going through the bottom door seal. If you open the window with the cable thus trapped you will find you can reach down, grab it and it will slide side-to-side with minimal pressure so no damage being done. Thanks. I've never heard the term "AGM" before (I know, I haven't LIVED!). Now I know more: http://www.driverstechnology.co.uk/car-batteries.h... I take it the 981 has only used AGM type batteries? If I want to double check, will I find "AGM" printed on the battery somewhere, or some other cypher?

DJMC said: Thanks. I've never heard the term "AGM" before (I know, I haven't LIVED!). Now I know more: http://www.driverstechnology.co.uk/car-batteries.h... I take it the 981 has only used AGM type batteries? If I want to double check, will I find "AGM" printed on the battery somewhere, or some other cypher? I don't think it will actually say on the battery but if you note the battery code and search for replacements on design911 or similar the description will tell you for certain. (I'd be surprised if the 981 didn't need an AGM battery though. If it has start-stop the oem battery will be agm.)

Yes it will say AGM on the roof of the battery and yes, all 981 onwards have AGM's.

TrackNutz said: Yes it will say AGM on the roof of the battery and yes, all 981 onwards have AGM's. Thanks. I was also unaware a battery conditioner could do so much to enhance the performance and /or life of a battery. I wonder if it's true? Time will tell...

Thanks for the informative posts. No I didn’t use the negative on the wiper post I did it straight onto the battery, to add to this mishap does it matter that my CTEK 3.8 does not have an AGM mode? You say the gateway needs to know it’s a new battery in order to calculate ageing, charge strategies, charge level, condition etc. but if I replace it with a like for like battery then isn’t it simply a case of resetting it all to start from scratch, rather than changing anything in the parameters? In which case the detriment of not getting it coded will be minimal? I’m also interested in the fact that some people have got low voltage warnings and I haven’t.

The snowflake setting is AGM

You still need to have the new battery coded even if it's like for like. Coding most importantly resets ageing (or life) to 100%. For example, if the battery manager was struggling to recover a battery that had dropped below 12.5v for a very long time, you'll see the voltage in the instrument cluster at around 15-16v. The Gateway values are (for example) state of charge @ 50%, ageing at 40% and condition @ 45%. Below 75% SOC the start stop will also not work. You then fit a new battery but don't code it. The calculated amp throughput that the manger thinks the battery needs to recover it is still the same. So it charges with a high voltage and high amperage (981 alternators are duty cycle driven and can adjust voltage and amps independently with a variable internal resistance). So your instrument cluster is still showing 15-16v. Your start stop still doesn't work and the new battery will take a battering. Now let's code the new battery in, all values are set to 100%, the alternator load is now minimal, the instrument cluster shows 12.8v with the engine running and start stop is happy again. A massive difference. Plus the new battery gets a full life expectancy. Imagine the battery manager as a librarian, it monitors every amp that's checked out and tries to ensure it's booked back in. It does this even when the car is switch off and monitors the battery sensor to see if you're trickle charging and measures amp throughput, then adds this to the battery profile/condition. A new battery will want for very little so the charge strategy is totally different. The actual values in the Gateway can show how many amps were used whilst the car was locked, what caused the car to wake up if anything, how much charge the battery had during its recent drive cycles, what causes the start stop to disable, etc. If even logs how many drives you do between 0-3 miles, 3-6 miles, 6-9 miles, 10+ miles to build a charge profile. It also logs the time the engine is run for throughout its life in 0-3 mins, 3-6 mins, etc. It's very very clever and hence the reason an OPC is far from ripping a customer off when they state you need your battery coded.

Brilliant post thank you. So what are the consequences of me not using the trickle charger correctly? I did use the snowflake mode because its cold outside but I didn't use the correct negative terminal, my CTEK wires aren't actually long enough to reach both terminals so I will need to look at this. Lastly why is a battery now so complicated? Is it purely for fuel saving, e.g. the more the gateway knows about the battery then the less dependency on the alternator and therefore the lower the fuel consumption? Thank you.

TrackNutz said: You still need to have the new battery coded even if it's like for like. Coding most importantly resets ageing (or life) to 100%. For example, if the battery manager was struggling to recover a battery that had dropped below 12.5v for a very long time, you'll see the voltage in the instrument cluster at around 15-16v. The Gateway values are (for example) state of charge @ 50%, ageing at 40% and condition @ 45%. Below 75% SOC the start stop will also not work. You then fit a new battery but don't code it. The calculated amp throughput that the manger thinks the battery needs to recover it is still the same. So it charges with a high voltage and high amperage (981 alternators are duty cycle driven and can adjust voltage and amps independently with a variable internal resistance). So your instrument cluster is still showing 15-16v. Your start stop still doesn't work and the new battery will take a battering. Now let's code the new battery in, all values are set to 100%, the alternator load is now minimal, the instrument cluster shows 12.8v with the engine running and start stop is happy again. A massive difference. Plus the new battery gets a full life expectancy. Imagine the battery manager as a librarian, it monitors every amp that's checked out and tries to ensure it's booked back in. It does this even when the car is switch off and monitors the battery sensor to see if you're trickle charging and measures amp throughput, then adds this to the battery profile/condition. A new battery will want for very little so the charge strategy is totally different. The actual values in the Gateway can show how many amps were used whilst the car was locked, what caused the car to wake up if anything, how much charge the battery had during its recent drive cycles, what causes the start stop to disable, etc. If even logs how many drives you do between 0-3 miles, 3-6 miles, 6-9 miles, 10+ miles to build a charge profile. It also logs the time the engine is run for throughout its life in 0-3 mins, 3-6 mins, etc. It's very very clever and hence the reason an OPC is far from ripping a customer off when they state you need your battery coded. My OPC fitted the CTEK Confort Connect eyelets directly to the battery posts, was this incorrect? Also with an uncoded (no serial number on the battery so nothing to enter/code via PIWIS) Banner AGM battery fitted my stop/start works normally?

SkinnyPete said: Brilliant post thank you. So what are the consequences of me not using the trickle charger correctly? I did use the snowflake mode because its cold outside but I didn't use the correct negative terminal, my CTEK wires aren't actually long enough to reach both terminals so I will need to look at this. Lastly why is a battery now so complicated? Is it purely for fuel saving, e.g. the more the gateway knows about the battery then the less dependency on the alternator and therefore the lower the fuel consumption? Thank you. The consequences are that you are physically improving battery condition but the manager has no clue, so will not adjust this in the battery profile. You could trickle charge it for weeks but the state of charge would remain at say 78%. So the manager loses information and therefore can decrease battery life. Yes, essentially it's for efficiency, fuel economy, euro emissions standards, performance (less torque loss when full open throttle - manager can cut alternator load if required) etc etc.

gtsralph said: My OPC fitted the CTEK Confort Connect eyelets directly to the battery posts, was this incorrect? Also with an uncoded (no serial number on the battery so nothing to enter/code via PIWIS) Banner AGM battery fitted my stop/start works normally? Do you have a photo? Both the connections and the top of the battery. If you have a 981 or newer, then yes it is incorrect to attach the leads directly at the posts and therefore bypass the battery sensor.

Hopefully 10 hours of my CTEK 3.8 will not have taken it too far out of its parameters...we'll have to see.

TrackNutz said: Do you have a photo? Both the connections and the top of the battery. If you have a 981 or newer, then yes it is incorrect to attach the leads directly at the posts and therefore bypass the battery sensor. No photo and car is on its winter holidays in storage. The eyelets are attached to the small bolts that are part of the fittings on the battery posts.

gtsralph said: No photo and car is on its winter holidays in storage. The eyelets are attached to the small bolts that are part of the fittings on the battery posts. Then it's wrong. Just grabbed this screenshot from eBay. At the bottom of the wiper assembly you should see the black rubber grommet. Through the centre goes the charging post which doubles as a securing screw. You can also just make out the small negative battery terminal sticker, to signify correct charging location.

Just some follow up on this, I used my CTEK to charge the battery to full (using the correct negative terminal this time!). It only took a few hours and I disconnected it for the night. In the morning I used a cheap voltage meter that plugs into the cigarette lighter, it registered about 12.3V plus or minus .1 every other second. I then turned the ignition on and got a similar reading. The car has been fine since but the voltage reading on the dash was 15v and stop start did not work so much, that said it's never really worked in my car (60 seconds at most) unless I turn the heater panel and PCM off then it lasts for 3-4 minutes. Anyway, am I right in saying with the engine off the battery should hold 12.5V? Edited by SkinnyPete on Wednesday 27th December 20:12

TrackNutz said: Then it's wrong. Just grabbed this screenshot from eBay. At the bottom of the wiper assembly you should see the black rubber grommet. Through the centre goes the charging post which doubles as a securing screw. You can also just make out the small negative battery terminal sticker, to signify correct charging location. I have done some research since last posting and the 981 Boxster SIT document states: “Every external charging/jump starting operation on the battery must be performed at the jump start terminal (positive battery terminal) and the corresponding ground terminal (on the wiper linkage). The negative battery terminal must not be used for external charging/jump starting since the battery sensor can be destroyed by voltage peaks during the charging operation/jump starting.” This supports your advice, however, I checked with two Porsche Centres this morning and their written advice was: ".... for conditioning the battery the charger needs to be connected directly to the battery posts (via the eyelets). And the Earth is used if jump starting is needed." I had storage company take pictures of my installation and the rather large wiper mechanism earth which are shown below: the wiper mechanism earth: Clearly the CTEK/Porsche eyelets cannot be attached to the wiper mechanism earth so for what it is worth that supports Porsche’s advice that a CTEK/Porsche conditioner is safe using the battery posts but for charging (implying a non-conditioning battery charger) or jump starting the wiper earth must be used because these processes will have voltage spikes (and CTEK/Porsche conditioner does not).

I have seen larger eyelets used underneath the wiper post fixing. If the battery is charged at the battery terminal it bypasses the battery sensor and will certainly keep the battery topped up, but as previously stated, will not add any info to the battery manager. This can decrease battery life, but hey, how will know the difference. Clearly there is a lack of proper info available in the literature.

TrackNutz said: I have seen larger eyelets used underneath the wiper post fixing. If the battery is charged at the battery terminal it bypasses the battery sensor and will certainly keep the battery topped up, but as previously stated, will not add any info to the battery manager. This can decrease battery life, but hey, how will know the difference. Clearly there is a lack of proper info available in the literature. Yup, that's a fair summary..

What about plugging the CTEK into the 981's armrest 12v socket? When I phoned my OPC last week they advised this was the way to connect it, also explaining that they run the charger cable through the door and shut it closed as the seal will give, and that this socket remains live to accept a charge even though it will cut out after 30 minutes if powering an accessory from it. The technician said they charge cars this way multiple times per day. He made no mention whatsoever of opening the bonnet. I've plugged my CTEK MXS 5.0 in this way, via the armrest 12v socket, and it's gone through its cycle fine. But is the OPC correct that this is an OK way to charge the battery?

Yes that is fine. It goes through the battery sensor this way so all good. Like they stated, the battery manager should see that a charge is being supplied so shouldn't shut off the T30SD lines.

SkinnyPete said: If I fit a new battery myself I assume I can wait a month and get it coded when my car is serviced? The current type of battery supplied by Porsche has a serial number which they are required to enter into PIWIS so if not a Porsche supplied battery, they can't install it in accordance with their protocol. Consequences; all the official advice and learned persons say it risks non-standard battery management behaviour such as failure of stop/start, damage to the voltage regulator and ultimately may reduce the life of the battery. Anecdotally I haven't heard of any of these happening BUT maybe with further service life there could be problems. Testing, you could have that done elsewhere to see whether you really need a new battery, but of course your Centre will connect PIWIS and see if anything else is causing the problem. Otherwise the price they have quoted is stupid and gouging. It should be around £280 inc VAT inc Porsche Club discount (if you are a member) and includes fitting and coding, coffee and biscuits.

Well I'm pretty sure my battery is past its best because everytime I start the car the voltage metre reads 11.9v so its critically low. Porsche want £420 to replace it but £40 of that is to diagnose the existing battery which im sure you'll all agree is waste of time. If I fit a new battery myself I assume I can wait a month and get it coded when my car is serviced? Edited by SkinnyPete on Saturday 30th December 11:39

gtsralph said: The current type of battery supplied by Porsche has a serial number which they are required to enter into PIWIS so if not a Porsche supplied battery, they can't install it in accordance with their protocol. Consequences; all the official advice and learned persons say it risks non-standard battery management behaviour such as failure of stop/start, damage to the voltage regulator and ultimately may reduce the life of the battery. Anecdotally I haven't heard of any of these happening BUT maybe with further service life there could be problems. Testing, you could have that done elsewhere to see whether you really need a new battery, but of course your Centre will connect PIWIS and see if anything else is causing the problem. Otherwise the price they have quoted is stupid and gouging. It should be around £280 inc VAT inc Porsche Club discount (if you are a member) and includes fitting and coding, coffee and biscuits. Thanks Ralph. By fitting a new battery I mean a Porsche OEM battery from the likes of Design 911, which is £200 delivered. By comparison Porsche gave me this breakdown; battery £280, labour £100, plus £40 diagnostics which they were really pushing hard for.

Design911 have an OEM Banner AGM 84Ah battery for £90.95 + VAT excluding any discount you might be entitled to. IF this battery is really the OEM battery for your car AND it has a Porsche serial number, that should allow someone with PIWIS to install it with the proper protocol. Might be worth checking the serial number point with Design911as if that is OK then it'll answer the point about being a proper OEM battery?

SkinnyPete said: Well I'm pretty sure my battery is past its best because everytime I start the car the voltage metre reads 11.9v so its critically low. Where are you getting that reading from? The only accurate place to take a battery voltage reading from is at the battery itself - virtually everywhere else you'll get some voltage drop.

All sounds like a total pisstake. I would just fit one from Design911.

gtsralph said: Design911 have an OEM Banner AGM 84Ah battery for £90.95 + VAT excluding any discount you might be entitled to. IF this battery is really the OEM battery for your car AND it has a Porsche serial number, that should allow someone with PIWIS to install it with the proper protocol. Might be worth checking the serial number point with Design911as if that is OK then it'll answer the point about being a proper OEM battery? This one you mean?: http://www.design911.co.uk/fu/prod132889/Car-Batte... Here's mine... Closest to this is: http://www.design911.co.uk/fu/prod132885/Car-Batte... ...but part number slightly different.

The link is indeed to the design911battery I was referring to. The issue is whether it has a Porsche serial number as the one in the picture you posted appears to have

Which number is the serial number? If it is the 999..... then the argument about installing a non-Porsche battery is moot because that number doesn't change much over time and so any battery can be installed and coded using the widely known 'serial number' de jour.

Hang On said: Which number is the serial number? If it is the 999..... That's the part number

gtsralph said: That's the part number Thanks. Where can I see the serial number?

gtsralph said: The link is indeed to the design911battery I was referring to. The issue is whether it has a Porsche serial number as the one in the picture you posted appears to have Your linked to £90.95+VAT battery is this one... Link: http://www.design911.co.uk/fu/prod132889/Car-Batte... That doesn't look anything like my 2014 981 2.7 battery, which is this one (photo of actual battery in my car)... The second linked to battery in my previous post IS very similar to my one... Link: http://www.design911.co.uk/fu/prod132885/Car-Batte... The part number is slightly different. It's 999.611.080.12 as opposed to mine which is 999.611.080.10 I phoned Graham at Design911 this morning - The "12" suffix is simply an updated version of the earlier part. BUT... he was suspicious that because Design911 buy direct from Banner the battery may not have "Porsche" branding as in the "example" photos on their web site, so off he went to have a look at the three in stock. When he came back he confirmed there is NO Porsche labelling on these batteries. For those with Porsche warranty I would suggest these won't be suitable and that your OPC will call them 3rd party although they are allegedly identical otherwise.

For those of you that desperately need to fit an OPC battery.... Go to local porsche specialist, get them to order from OPC, get them to fit it, get them to code it in for you, job done. Don't go back into your OPC and tell them what you just did. They just will not look that hard as long as all looks good... I dare not say anything else as this post in some ways just prooves that Porsche are a thieving bunch and only interested in getting your money, but the realists on here will already know that. £100 just for fitting a battery is disgraceful in my book. Obviously there is good information on this post which is well worth knowing. Merry christmas, and a happy new year to you all. I still love my Porsche. Gadgit.

They're interested in keeping your battery life at its maximum. Not sure about stealing your money. I'm not sure if I can explain any further than I have done already. Some very interesting views on here indeed.

DJMC said: The part number is slightly different. It's 999.611.080.12 as opposed to mine which is 999.611.080.10 I phoned Graham at Design911 this morning - The "12" suffix is simply an updated version of the earlier part. BUT... he was suspicious that because Design911 buy direct from Banner the battery may not have "Porsche" branding as in the "example" photos on their web site, so off he went to have a look at the three in stock. When he came back he confirmed there is NO Porsche labelling on these batteries. For those with Porsche warranty I would suggest these won't be suitable and that your OPC will call them 3rd party although they are allegedly identical otherwise. Good work, they advertise as OEM hence my IF Design911 advertise 360mm Girodiscs which Girodiscs told me they abandoned 2 or 3 years ago because of occasional fit issues (350mm is OK) and they have told Design911, but both sizes are still on their site. Cargraphics are the same, both basically distributors who don't have the experience of fitting the parts and so can quite innocently give misleading advice.

At least Graham at Design911 offered to check the battery to make sure it satisfied a car under warranty. He volunteered, I didn't ask. In future though I will ask for a physical check of any so called OEM parts. Saves sending them back if wrong.

Do we think independents will have the software to connect to the gateway? Must be cheaper than paying Porsche £100 to do it.

Just to follow up on this, 3 months on the car has not had a problem starting so maybe it was a one off. Don't get me wrong it doesn't inspire confidence when starting but then no Porsche does unless its fitted with an aftermarket battery!

Perhaps you guys should ask yourselves the question, what happened before, (in the case of Boxster/Cayman) the 981 and stop/start and energy regeneration, how long did the 987 batteries last, did they need coding, were they expensive AGM. Regeneration is I believe the cause of the high 15-16 volt charge, this is to cram as much voltage into the battery in as short a time as possible, I don`t believe you will see this high voltage when the car is under it`s own power, more like 14.4volts, if you see a low SOC in your battery it is probably caused by the EMU allowing the battery to run down to around 75%, this is to make room for any high voltage regeneration, if you don`t get much regen you end up with a partially charged battery, short journeys make that worse and shorten the life of the battery. I own a Merc coupe and just purchased a Cayman 981, for lhe last 10 months The Merc has been running with the battery sensor disconnected, I did this to get rid of stop/start, without the sensor in play the EMU also reverts to a standard continuous rate of charging (pre 2011) of around 14.4 volts, the battery now remains fully charged or near to at all times, no need to code new battery, no need to replace with AGM, that`s only needed for stop/start and regeneration.

Bit of a resurrection here but I have not visited the Porsche forum for a while. I need a new Battery for my 981 Boxster 2012, I approached the local Porsche Centre who quoted £279.79 for a replacement battery. I asked if that included the "coding" to the car, he went away to ask and said it didn't need it on my car, only later ones, and I could fit it myself. I presume he was talking about a direct replacement for the original. Totally confused here for a definitive answer - I can get a suitable AGM battery from Halfords for £142, but would that need to be matched to the car?

I'm sure there was a thread somewhere that basically said coding to the car was unnecessary. https://www.porscheclubgb.com/forum/tm.aspx?m=1066... That said if you're running warranty you'll still need the official Porsche branded battery to pass the 111 point check. I occasionally changed the battery on my 981 without any error codes. I think the only thing it had to relearn were the one touch window settings (just open and close after power restored to reset them).

Just wondering what people have done under the extended warranty? OPC's obviously come in quite a bit more than indy. But as battery needs coding to PIWIS presumably this would show up in ECU if OPC was ever checking car (such as for a warranty claim).

SV_WDC said: Just wondering what people have done under the extended warranty? OPC's obviously come in quite a bit more than indy. But as battery needs coding to PIWIS presumably this would show up in ECU if OPC was ever checking car (such as for a warranty claim). Most if not all decent Indys have PIWIS or equivalent that can code a new battery to the car.

SV_WDC said: Just wondering what people have done under the extended warranty? OPC's obviously come in quite a bit more than indy. But as battery needs coding to PIWIS presumably this would show up in ECU if OPC was ever checking car (such as for a warranty claim). Aren't you allowed to get work carried out anywhere provided they use Porsche parts?

Well after 13 years of use I have finally replaced my cars battery. Not because it failed, but because I have a euro trip coming up and it felt like a risk. Surely it could not last much longer? Paid Porsche £323 for the privlidge and fitted it myself in less than 15 minutes. Need to get the car coded now. Porsche wanted £280 which I politely refused.

^ do they actually need coding? I replaced mine myself, like with like during Covid when dealers were closed, it's still running well no issues and no coding...

jimbo761 said: ^ do they actually need coding? I replaced mine myself, like with like during Covid when dealers were closed, it's still running well no issues and no coding... If you read the earlier pages in this thread, then yes. It'll still work without, but it'll last much longer with (apparently).

If you replace the battery with one of absolutely identical electrical specification then coding is NOT necessary.

Panamax said: If you replace the battery with one of absolutely identical electrical specification then coding is NOT necessary. The reason the battery needs coding is because without coding the car has no way of knowing it has had a new battery fitted, so it will be treated like the original 13 year old one (good work OP). A new battery is charged differently to an old one and if it isn’t charged correctly you will not be getting a it’s full potential or life expectancy out of it.

This from the website of leading battery manufacturer, Banner. I've added bold to the essential detail, "...the battery energy management system must first “learn” the characteristics of the new battery. During this phase, some comfort functions may be restricted. After several driving cycles, the system will usually work perfectly again. It is important that the replacement battery matches the original battery in terms of size, technology (e.g. AGM or EFB) and performance . Minor deviations in capacity or cold start can be overlooked."

The charging system needs to know what it's trying to charge - that's where the detailed electrical specification of the battery comes in. Now ask yourself, how does the charging system cope if the battery's been completely flattened? Answer: it adjusts. In exactly the same way the charging system can adjust when an identical new battery is fitted. Edited by Panamax on Thursday 23 April 13:35

The charging system is designed by Porsche, the battery manufacturer just supplies an AGM battery to the spec requested by Porsche to work with their charging system. The way the system works was explained in great detail to me by an OPC tech who does this as his day job, I have no reason to doubt what he said.

I'm sure that if someone who is close to you has a n Icarsoft or ThinkDiag etc they will be able to code it in for you. Where in the UK are you?

https://www.youtube.com/watch?v=gs7C34WPJvk

Took the car to an independent Porsche garage. It absolutely 100% needed registration/reset.