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It seems like those vehicles that have their battery drain after just a couple of days have some kind of abnormal parasitic current leak somewhere. Porsche is known to have alternator diode leaks, and there are easy tests for that, where when testing with a diode tester and the alternator negative connection, you find that there is on or more diodes that have voltage on both directions.
On the first day in the shop, Porsche tested my GTS for a battery drain and reported none.
On the first day in the shop, Porsche tested my GTS for a battery drain and reported none.
Classic answer from many incompetent Porsche dealers for many problems that customers have.
The test for a battery abnormal leak is very simple and any competent independent Porsche shop can do it, and which is how many customers found the root problem with their vehicles.
Batteries do not drain overnight, or in a week, unless there are defective or there is an abnormal current leak, which is why it is tested at the battery terminals on problematic vehicles.
Well I just complained that the battery light flashed here and there and my auto start/stop didn't work sometimes. (Did happen once some time ago)
They performed WMJ9 - RE-PROGRAMMING GATEWAY CONTROL UNIT (BATTERY SENSOR) 3054303 WP97 0.48
PERFORMED RECALL WMJ9
Hopefully that doesn't happen to start a problem instead of proactively heading off one!
They did not perform a SW update on my infotainment like requested due to Carplay rebooting... argh.
Well I just complained that the battery light flashed here and there and my auto start/stop didn't work sometimes. (Did happen once some time ago)
They performed WMJ9 - RE-PROGRAMMING GATEWAY CONTROL UNIT (BATTERY SENSOR) 3054303 WP97 0.48
PERFORMED RECALL WMJ9
Hopefully that doesn't happen to start a problem instead of proactively heading off one!
They did not perform a SW update on my infotainment like requested due to Carplay rebooting... argh.
But that recall is from May 2022, I haven't seen Porsche contacting me about any type of recalls..
Maybe my 2019 CS may not be involved in that campaign?
Last edited by PorscheACC; 08-29-2023 at 02:07 PM.
For the not-yet-Porsche Cayenne owners, what are these feature settings exactly?
"...In addition, I disabled my AS/S Start/Stop soon after I bought it. I am sure that helped too."
I am taking notes for myself but don't get what AS/S Start/Stop means and where in the car menu where it can be disabled by the end user.
Thanks in advance.
Originally Posted by PorscheACC
Knock on wood..
I have been up to one month on a trip outside the states, and my parked 2019 Cayenne S was fine after returning. Though, I gave it a full charge days before I parked it.
In addition, I disabled my AS/S Start/Stop soon after I bought it. I am sure that helped too.
It seems like those vehicles that have their battery drain after just a couple of days have some kind of abnormal parasitic current leak somewhere..
Porsche is known to have alternator diode leaks, and there are easy tests for that, where when testing with a diode tester and the alternator negative connection, you find that there is on or more diodes that have voltage on both directions.
In addition, crumbling headlight wire harnesses have been found to cause almost overnight battery drainage, on some older vehicles. I was surprised to see the wires in the harness just crumble after wigling the harness.
It seems like the wire insulating materials didn't hold the years of hot/cold exposure.
Last edited by mxp0; 08-29-2023 at 10:56 PM.
Reason: minor
For the not-yet-Porsche Cayenne owners, what are these feature settings exactly?
"...In addition, I disabled my AS/S Start/Stop soon after I bought it. I am sure that helped too."
I am taking notes for myself but don't get what AS/S Start/Stop means and where in the car menu where it can be disabled by the end user.
Thanks in advance.
The AS/S (Start/Stop) feature lets your Porsche engine turn off when you stop at a light or when you stop, to save gas. It only works when the drive in in Normal mode, and will not work in Sports mode.
The vehicle always reset back to normal mode after you start the vehicle, so you always have to turn that feature off..
Most people like me hates this feature, because it is buggy (sometimes turns off the engine before you stop, steering issues with an off engine, etc.) and it stresses the battery, which already has overcharging problems by the BMS and has issues with the battery controller/sensor, which kills the battery for those unlucky ones.
Unluckily, you need a high end scanner device to program the AS/S so to disable the AS/S feature. Best thing I did to my vehicle was to disable this feature.
Whatever you do, do not buy any Porsche vehicle with Lithium batteries.. Porsche is screwing its customers with high prices, poor service, and weeks/months waits for parts..
They are charging around $1,000+ just for labor in installing a $2,200 battery on 9YA 2019+ models where it is very easy to install and register, since it is the same registration method as any other battery since 2009 on vehicles with BMS ( Battery Management Systems).. but there is a lot of fearmonging around..
Almost sounds like Porsche knows that their future vehicle sales will sink, so they are putting plastic in their parts, making aluminum screws that constantly fail, charging skyhigh for labor, etc. so that they will cash on their customers for years to come deeply profiting from expensive parts, expensive labor, and making dealers more profitable, all at the customer cost.
Vehicle companies normally improve their part's design and quality, but Porsche is going backwards which is not a good sign.
08-27-2023, 11:14 AM
