I've been having strange battery problems lately.

Today after starting the car I found I could not change the level of the air suspension. Pressing high level I would get "Not possible" and pressing the PASM button to sport plus level it would try and change mode but I would get "Chassis failure".

I drove it maybe 100 meters in a loop, parked back and found changing the level working again. Later on in the day I tested it again and found I could not get the level to work at all even after doing the 100m loop again. So after dinner I went for a 50km drive. I started the drive in what I thought was comfort mode but after 40kms I looked down and noticed it was in sport mode on even though I had not pressed it. Changing level worked again after that drive, even after switching the car off and starting it again.

Before I set off on the longer drive the battery voltage was reading 11.9v on the dash with ignition on but engine not running. During the drive the voltage quickly climbed to 15v, which I have never seen it reach before.

Ever since I got my car I've suspected my battery is on the verge of dying, however it has never failed to crank over and start since I picked it up. Is it normal in a Panamera to have its electronic systems stop working before the car can crank over and start? I am more used to vehicles where the electronics continue to work after the battery stops being able to start the car.

Another symptoms I get is the tailgate sometimes gives me a triple beep. Today I even got two triple beeps in succession, it seems to happen more often when the car is cold.

I've got a CTEK MXS 5.0 charger and I use it about once a week. It seems to boost the battery voltage reading to 12.6-12.8 on the dash but after a few days the voltage reading will drop to 11.9-12.0.

Wondering if I need to change the battery. I am thinking of installing a Lithiumax RESTART9 instead of an AGM.

 

If you turn on the ignition and see battery voltage below 12 after the car sits overnight, chances are you need a new battery. That was my situation on my 2013 Panamera which I bought a month and a half ago. It never failed to start, but twice after working on the car for a long time with the doors open, gps on, and so on, the cranking was less than robust. I was unable to determine the age of the existing battery. The regular service events which came with the car are a bit vague, like "Performed scheduled service" without actually noting what was done, so no telling when the battery was installed.

Although I didn't suffer odd behavior of any of the components, I wouldn't be surprised if a very sophisticated car like the Panamera would act up with a marginal battery even if it would still start the engine. The 15 volt charging indication might be something of a worry too. I think mine is about 14.2 to 14.4 volts.

I bought a DieHeard AGM which was an exact fit and registered it myself using my relatively simple code reader.
The job was very easy, not time consuming, and saved hundreds of dollars when compared with having the job done by a Porsche dealer.
If your battery is old, why not change it? Plus, if you constantly think your battery is on the "verge of dying", as you say, that is no way to go through life. It takes all the fun out of owning a nice car, doesn't it?

 

Which code reader did you used to reset the battery?

 

iCarsoft Auto Diagnostic Scanner POR V2.0 for Porsche with ABS Scan,Oil Service Reset etc.

$145 from Amazon

 

A quick update, I wanted to buy a Lithiumax restart9 battery to replace the 80 ah AGM. Unfortunately the process of purchasing one was too difficult and I didn't end up going ahead with the purchase. A shame really because I think LiFePo4 starter batteries are great based on my experience of them in my motorcycle.

Instead I've picked up a Neuton Power 850 CCA AGM. I'm going to install it while the car is connected to a CTEK charger and try a Foxwell NT530 to program the new battery in.

Hopefully the charger will allow me to keep all my settings and I'll report back on whether the Foxwell worked for programming the new battery.

 

I don’t get it. My vehicle is connected to a 4amp smart charger 24x7 if not driven. If I change out the battery while connected to the charger, how would the system detect it? Currently the voltage is measured 12.4v or 12.5v at all time. How would it detect a new or used battery if either battery will measure 12.4 volts?

 

it wouldn't, even if you didn't use the charger during battery change it wouldn't detect it.
You need to tell it that there is a new battery in there, otherwise it will continue to use the older battery charging rates.

 

I'm so annoyed that my Durametric can't do this.

 

Agree. That is why I recently sold my Durametric Pro cable and set up a PIWIS 2. Can be done very affordably. PIWIS 2 only works up to MY 2018. After, need PIWIS 3 ($$).

 

Installed the new battery while connected to the CTEK charger and didn't have to reset any settings. The process was pretty straight forward with the only issue being the hold down bracket being a tight fit. I suspect it may be due to the new battery being a bit wider.
Programming the new battery ended up being partially successful. In the Foxwell you have to input various parameters, the brand, the AH size, the serial and the part number. Some of the fields are drop down boxes with selections (brand, AH). I selected Moll, 92 AH, put in a serial the Foxwell provided as an example and put in the part number (7PP.915.105).
The battery change was accepted and the new battery is programmed in but there is a diagnostic setting called "Battery change coding" and is reporting "not OK". I assume this means it isn't accepting the battery as a valid OEM part or I have inputted something incorrectly like the part number. I did test whether the car has changed its charging and voltage is only reaching 14.6, so it is definitely using new charging rates.

Unfortunately, the battery is still losing charge, after installing the new battery (which I had charged to full before installing) I went away for a few hours and when I returned the battery had lost 10% charge, so there is a drain somewhere while the car is parked.
This drain is probably what was causing the voltage drops on the old battery and the drop in voltage then causes other systems in the car to stop working correctly. Many of the systems in the car seem to have a min voltage limit, if voltage drops too low they stop functioning correctly and then throw a voltage limit error/code.
The PDCC system is one of these, after changing the battery and resetting the codes on the system I noticed a remarkable difference in the handling of the car.

While removing the old battery I discovered a tap on the positive terminal. I wasn't able to trace what it was powering but I disconnected it and I've not noticed any change in the functionality of the car. Does anyone have any ideas on what this tap was powering?


Red line tapped into positive terminal

I didn't restore the tap when installing the new battery and I'm still finding there is a drain. Anyone got any ideas on how to diagnose the source of the battery drain?

 

I'm still struggling with finding the source of the battery drain but I decided to give programming the battery a second go to try and change the status of the "Battery change coding" diagnostic status.

So I did some research on alternative part numbers and actual serials of OEM batteries. I also watched a video of someone replacing a battery in a Macan with an Autel unit.

I found the 92 AH part number is 7P0.915.105 and all the Porsche OEM batteries I could see had 15 character serial numbers (205 MLA1885544A). In the video showing the Autel coding in a battery, the Autel unit asks for a 15 character serial as well.

What is a bit frustrating with the Foxwell unit is it asks for a 10 character serial number. Even if you chop off the first 4 characters of most battery serials, "205 ", it still leaves you with an 11 character serial number, for example MLA1885544A. Which is one character more than the Foxwell allows you to enter.

So I did my best and coded it a second time. It used the new part number and I entered a 10 character approximation of a real serial. It accepted the battery change but "Battery change coding" is still "not OK" so I assume the ECU just doesn't like how the Foxwell does the coding. My guess is it is something to do with the 10 character serial requirement.

Now back to figuring out that drain....

 

Hook a meter up to the battery and then start pulling fuses, one by one, replacing them before you pull the next. When you pull one that causes a big change, there's your drain.

 

That's a lot of fuses. LOL

 

No idea; however, it is clearly NOT a Porsche component or a factory component from any other reputable auto manufacturer. They would never use a crimp terminal like that piggy backed onto the battery clamp bolt.

Look around for some kind of boot-leg device. Have you noticed anything like this in your rear window?

 

Maybe for a dashcam?