jibinbaz

@enzowhatever I would like to get this conversion kit. Can you please point me in the right direction ?

RG928

Is there a temperature restriction on keeping these batteries on maintainer? We are in a cold snap and it's been on the maintainer for days but temps are supposed to get to -10 or below. Just wondering its in the garage but still pretty cold, maybe 25-30 degrees in the garage. Any feedback would be appreciated. Thanks

t-design

I had to learn a lot about those faulty LGChem batteries, and thought I'd share simple solution I used. I'm sure it's mentioned here in many different threads, but I'll share my journey anyway.

Short version first:

Symptoms : 2019 Cayenne, 50K miles, 4.5 years old. Came back from the trip to airport parking lot - and the car is dead. Michigan winter, temps below freezing, about 2 weeks... I guess it was the time for that faulty LG Chem to go dead. Battery voltage reads 0.

Cause: the faulty BMS (Battery Management System) on the LG Chem LiFePO battery goes into protection mode when the voltage goes below some threshold (10v?). It physically disconnects the battery terminal "to protect the battery". It than supposed to connect it back when the BMS feels the proper charging device attached. BUT IT DOESN'T!!! So for all intents and purposes the battery is dead, and usually thrown away and replaced with a new $2 200 LiFePO battery at the dealer.

Solution: Send the battery (or remove and send BMS) to the shop in Mineola, where they reset the internals to connect the terminal back (as battery BMS supposed to do automatically, but does not).

Longer Story:

Tried to revive car with the little jumpstart battery I had - not a chance. Tried jumper cables from friend's car - it tried but didn't take. Eventually car was started from some serious looking jumpstarter like this https://www.jbtools.com/jump-n-carry...hoCNhgQAvD_BwE

Didn't have any troubles driving car from airport to the house, but there was a nasty message on the dash, saying "battery needs recharging" or something like that. Came home, run car for two hours... Turned the ignition off - car is dead again. Measured the current on terminals under the hood - zero V. Attached charger - nothing.

Went to couple of car stores around to get a new battery - they don't have it. Nothing. Than I started to suspect bad things, went on Rennlist and learned about yet another wonderful decision by German Engineers to put a $2200 faulty LiFePO battery into 9Y0 Cayenne!

We tried all the things people mention online : jumpstart with powerful device to wake up the battery, attach to another battery AND a lifepo charger... None of the things that works on generic LiFePo batteries worked on LG Chem unit. It was very clear that battery is completely disconnected by BMS, and it's not waking up like it supposed to. Page 72 of the Cayenne Manual says it should reactivate and connect to car's electrical system after 10 minutes of charging... Only in the fantasy world of German Engineers Not in the real world.

After that the next step was to try the "reactivation" of BMS by third party companies, as mentioned in many threads. So I got in touch with Anthony from Premier Autocare and Performance in Mineola (no affiliation). He sent the instructions how to open the battery and remove the BMS circuit board (so we don't have to ship whole 28lbs), and overnight it to them.

The real battery terminals, accessible after you open a battery - read 6V at that point. I charged the battery through real terminals and LiFePO charger, while Anthony was reprogramming the BMS and shipped it back. Two days later - battery is back together and works fine. Wife gets the car back and I'm a hero! Also, working with Anthony was a pleasure, fast answers and shipped the board back to me the same day.

The hardest part in whole process was to open the battery. The lid is simply glued onto the box, and it takes some patience and perseverance to open it without damaging too much. After it's open - it takes literally 30 seconds to remove the BMS board. Of course you can ship the whole battery, it'll just be a LOT longer to get it back, as you can only ship batteries by UPS ground.

In conclusion - knowing how Porsche dealers work, it's yet another case when dealer will charge you a price of a new part, when the "old" part can be fixed at a fraction of the cost... I'm pretty sure that ALL dead LG Chem batteries (after leaving car for a long time with no charging) can be revived this way. It will also be faster then ordering a new battery, as dealers usually don't stock those.

Why would German Engineers do that to us - ridiculously priced battery that is absolutely not necessary on Cayenne... is beyond my understanding. I will be converting to AGM battery if something happens again.

PorscheACC

Great and helpful 9Y0 Cayenne LiFePO4 Lithium battery post and information.


No need to send the battery, but just send the controller/sensor hardware is a great and handy solution. Then, they can just send you a program or reprogrammed controller/sensor.

I am appending a link to their website from the information you provided, for anybody needing it.

Premier Autocare and Performance - Auto Repair Shop in Mineola

https://premier-autocare-and-perform...edium=referral

TonyM305

Would this make the yellow "service battery" warning go away?

rjk25

Another question is the new battery that porsche is installing going to be trouble free. Did they fix the issue?

t-design

Don't know. Mine didn't give any warnings and was in good shape. Until it just went dead and unresponsive after two weeks on the parking lot in winter.

ThaiGuy

For folks who already have their batteries 'temporarily fixed' by the TSB - Gateway controller unit and have the yellow light coming back afterward, how long have you been living with the yellow warning light? It has been less than a week for me and I am trying to determine the next step. Don't know if a dealer can re-apply the TSB, but it looks like there are three options.

1) Remove BMS and ship to have it reprogrammed (see posts from t-design above)
2) Replace the whole battery - do not know if the replacement will be a good non-defective unit
3) Do nothing and endure with the light and sound with unknown event when the battery is going to be flat dead

PorscheACC

I don't recommend AUTEL devices, but I wonder what would be the full battery diagnosis of your LiFePO4 battery/BMS is when performed by a professional shop with a professional OBDII/Battery device that supports Lithium batteries.

The health of the Lithium battery is independent of the vehicle charging system, and the root problem may be the battery-cells/controller/sensor, may be the vehicle charging system, may be another Porsche software bug, etc.

It would be optimal to find the real root problem..

rjk25

So far I'v had the yellow warning light for over 2 months. I'm on the fence on what to do.

PorscheACC

Have any shop with the right tools evaluated what is your battery overall condition?

It can be an internal software code within the battery controller/sensor that may need to be reset with special Porsche tools.

There are normally battery voltage tables for each battery brand that can tell you the overall health of your lithium battery based on the overall voltage. They can do a load test to check the power delivery.

If it is not the battery, then it is the Porsche software that needs to be reset somehow.

The main point is why change a good battery, if maybe the battery is not the root problem..

ec135what

Hello all- here is my experience with my 2019 Cayenne Base.
The Porsche Service Center of South Atlanta re-programmed my battery sensor and cleared the "low battery" message in January 2023 at 50K miles and was covered under recall/ warranty. I received the "low battery" message again 10 months later at 55K miles. Called and spoke with Service Manager who said I'm no longer covered to repair and clear the nuisance fault. Nor did he help provide any assistance, advice, or options. The NHTSA shows Porsche's technical service bulletin that explains the known issue in detail. (also attached on this forum). I reached out to Porsche North America who escalated this to a specialist to see if they can give me "goodwill" assistance help in getting this resolved. All the PNA specialist did was contact the service center manager and see if he would do anything about it which he said he will not. The specialist told me the service center may have helped if I had an already established relationship at that service center. (Basically they will not help me since I have not spent any money there). I was under the impression that the specialist from PNA had the power and authority to have any Porsche dealership or service center repair any Porsche and cover the bill. Apparently, they only cover the bill if the dealership or service center is willing to do the work, which the South Atlanta Service Center would not. I would absolutely furious if my vehicle was inoperable because of this known issue. The battery is currently functioning and operation as normal, except the display still shows the "low battery" message. I plan to "ride it out" and try to clear the fault and keep going until the battery ultimately fails. Then replace it and buy a more reliable vehicle from a more reliable brand. I purchased this vehicle with high expectations of Porsche to be of exceptional quality and service to customers, but for them to leave me with this issue at 55K miles is definitely making me want to steer clear of the Porsche brand in the future. I have worked in aviation quality for over a decade and this is not quality to me at all. I understand things break and fail, and I probably wouldn't even be posting this if the cost of battery replacement was reasonable. But $2000-$3000? That's more than absurd to say the least. So on a scale of 1- 10, I rate my customer service experience with Porsche a 0 and will probably be "one and done".

flarpdoo

2020 Cayenne Turbo lowish milage ~15k.

TL;DR - battery seems to be losing .2 to .3 volts in 24h, suspect large parasitic drain? or fubar'd battery?
Car was recently serviced at a main dealer (30k service), so wondering if it could be work or some software update causing shenanigans.
Car is in a garage and warm enough (~15 C / 60F) so no cold exposure.

Background below.

Serviced (30k service) on in early December, left for a few weeks while we were out of the country - came back to the car entirely dead - tried to bring it back with the Charge-o-mat, no luck - was evidently in the low voltage/protect state - Roadside came by, jumped it - all fine.
Car ran an aggressive charge 13.8v for around 20 minutes, then I took it for an hour drive - all seemed ok - no alerts/warnings - showed 13.1v after parking it. Out of caution left it on the charge-o-mat over night, woke up to a battery showing 13.3V with a complete charge (i.e in float mode)

Did a few 100 miles over the next few days, no issues, voltage around the 13.0/13.1 mark while driving and before start. Starting usually see a .1v dip dip (i.e 13.0 -> 12.9) then it recovers.

Parked up on Sunday, car entirely dead by Friday (~5 days), seems a bit odd. Had bought the clips to attach to the battery but couldn't wake it up - think I was doing it wrong tbh - but again roadside came around and jumped it - though the technician this time was less familiar with the process.

His gear suggested the battery was reading 12.4v after it woke up, jumped it car ran an aggressive charge 13.xV incrementing all the way up to 14.3V before dropping back down - took about 40 minutes - all seemed ok - no alerts/warnings. Again, put it on the charger overnight.

After parking the car at 13.2V on Saturday - I checked every 12h, after 12h it was down to 13.0V after a further 12h down to 12.8v - seems a large drop, haven't tried to start it - just put the charger back on.

Wondering if its a fubar'ed / dying battery - or some sort of severe drain as a result of some work or software updates after the service?
Drain feels like the most likely thing - given the battery can cold crank without any real issues, and do this multiple times in between short runs (10-15 minutes of driving).

PorscheACC

Best way to know is running a parasitic drain current at the battery.

Should not be more than 0.50 amps. after the USB and electronics in the vehicle turns off..

If you have non-OEM accessories installed, or sometimes cellular interfaces, in your vehicle, sometimes they can keep the electronics awake and can drain your battery fast.

Second, you can run a Lithium battery test to determine your battery health, capacitance, and power capacity.

Porsche, BMW, etc have large battery drains when your wireless key is close to the vehicle and your comfort entry access is active.

The vehicle comfort access keeps waking up the wireless entry controller and keep draining the battery continuously. You need to keep your key remote away from the vehicle or in a radio wave blocking pouch/box, when you are home.

t-design

Just physically disconnect the battery - it's in passenger's footwell - real easy to do - and check voltage after a day. You will see what's what.