Expat444

Just had my battery replaced today, 2014 CS, 66.5K miles, $540 including labor, cleared lots of low voltage induced codes.

ewenc126

IXIXI

hacker-pschorr

My local Indy mechanic has spent a considerable amount of money to have equipment on hand to do the 5% of coding for BMW's your typical consumer stuff cannot do (like code for a new battery).

Similar equipment for Porsche is significantly more expensive, and he simply doesn't work on enough of those to justify the cost. Point is, more and more coding is needed for even simple items (like window switches) that will require expensive equipment most consumers will not have access to.

You may be right on your assumptions for the Cayenne, but if these are anything like BMW's, it's imperative to the health of the battery and all electronics for the system to know a new battery has been installed:

http://www.bimmerfest.com/forums/sho...8&postcount=13

Just an FYI, I have no idea if the Porsche systems are as touchy as BMW's.

deilenberger

I suspect the difference I saw vs what you saw was due to the charge state of the batteries. Mine was on a brand new battery that I'd left on a smart charger overnight before installing it. Yours, showing 12V when the vehicle auto-stops indicated a partly discharged battery - and in that case - I can believe the system may well provide max charging rate to it (which is 14.7V for an AGM battery) in either mode. At the time I originally saw this behavior I was purposely observing the charge voltage and pattern rather closely to make sure the new battery was behaving correctly. Once an AGM battery IS fully charged - the charge rate should back off to around 13.6-13.7V. Failure to do so on a fully charged AGM can cause it to overcharge and vent. (AGM aren't really "sealed" - they use a mat between the plates that absorbs and retains the electrolyte so they won't spill if tipped or leak if punctured - but they still DO require a vent fitting since they can boil off some of the electrolyte by overcharging.)

Your believing it's true or not is of no concern to me. I only reported what I observed and was able to reproduce repeatedly. Several other people at the time tried it and also observed the same thing. As always - YMMV

mikeearly

I realize that this discussion on coding is never going to be resolved to everyone's satisfaction --- I can say that coding on my 2013 Carrera S did matter -- I had the Porsche dealer install a new battery to make sure the coding service was done -- after the new battery was installed the volt meter was reading way too high in my opinion (never below 13.8) and took it back and met with the shop foreman -- he took it back in the shop and came back and told me that one of the new guys had installed the battery and had set up the "wrong" code -- once he put in the "right" code the meter was working as I expected it to --- so this doesn't prove that you need the dealer to code it but it did prove to me that there is a "right" and "wrong" code for my car......

deilenberger

Actually - quite simple to tell if the dealer can/does code the battery entry in the Gateway. If someone in the LA area who has had this done by a dealer - and was charged for coding - would like to meet with me - my iCarScan can read the "slots" in the coding memory where new information would be written. On mine - there is only the original battery information in the first slot. If there was information in the 2nd slot - that means it was written there when a battery was changed.

I'm available most anytime, currently staying in Lake Balboa.. hit me up with a PM and we might be able to solve this mystery. We'll plug in the iCarScan and see what's written in your memory - won't change a thing - just read it.

scb71

A couple of battery questions for a DIY person- I am not going to the dealer to swap out a battery. Thought it would be better to just tag into a battery related post vs starting new but can move it if needed.

How/when do you know to replace the battery assuming there are no warning messages? I am wondering if I should proactively replace the battery in my new to me 2012 S but only because the auto stop/start function rarely operates and when it does it doesn't stay off for long. It goes into eco mode for maybe 10 seconds and then it restarts. I assume this is due to battery drain and capacity. This is also after I charged the battery overnight via the Porsche charge o mat cigarette plug trickle charger I still have from a prior 911. I used the charger simply because I noticed the auto stop wasn't kicking in at all before. Post charge it does but again only for a few seconds.

Is that grounds for replacement?

Secondarily if/when I do swap the battery - what will happen if I do not connect a battery via jumpers under the hood to save memory setting when changing the battery? I do not have a memory saver device but I suppose I could buy one if it is absolutely needed. Could I use jumper cables and link another battery to the under hood connections while I swapped? Or I could hook up the Porsche charge o mat into the cigarette lighter if that would do anything. Or I could do nothing and then have to deal with whatever issues arise from losing memory.
I would greatly appreciate any and all comments on this.

Thanks in advance

Expat444

Hi
I can't answer it all but I can give some background on why I replaced my battery (2014 66K miles), I had an odd situation where the car refused to re-start when I was driving with auto start/stop so I had to remove the keys etc before it would start, I then started getting odd behavior from the parking sensors and finally had a coupe of occasions where the car had a hard time starting so I took it to my local independent mechanic and they tested the battery before replacing it and clearing a whole bunch of stored low-voltage error codes.
Good luck.

deilenberger

I'm skipping your first question since I think you've already answered it yourself. The stop-start is a big clue.

On your second question - NO. Do not connect anything. Modern vehicles don't forget. NVRAM is a wonderful thing. There is no need to hook anything up, and there is a chance of doing harm doing it (there is a thread on this happening..) Just replace the battery and get on with life.

Good luck!

walteryar

I connected jumpers to the under hood connections without starting the other vehicle. just bag the terminals when you pull them off the old battery. all settings were saved, no error codes.

TheCayenneKid

SCB71 - I noticed my Cayenne was having a hard time starting (turning over a lot) so I'm proactively changing the battery nextweek. I have a 2011 Cayenne S (~<65k) and I do believe the OG battery is still under the seat judging by the records. She was a Florida Car before coming to New England and I think the cold winter on an old battery really sapped some juice. One Particularly weird thing I noticed - after a week long vacation, the car really struggled to start, turning over a lot... Once Started, I had a red engine light and it said reduced engine power... I let the car idle and the warning did not go away. I turned it off and let it sit for a bit and then it started up just fine. I'm not sure what exactly caused that Reduced Engine Power Warning, but the car was not having it at the time of display, just moving it out of my garage and down the driveway the car felt like it wasn't firing on all cylinders. As mentioned, the problem has not come back (thankfully) but I am going to swap the battery to be sure it doesn't, and to ensure I'm not hurting anything by cranking it for longer than necessary after a long weekend or sitting for a few days.

For what it's worth, I was quoted $250 for a Bosch Battery by my local shop. He said a Porsche one will run at least 3x as much so I opted to go for the Bosch. I'll try and provide an update next week post install if it cranks any less on cold starts.

deilenberger

Your 2012 Cayenne is equipped with auto start/stop - which I assume you have turned off.. but it's a good test to see if the vehicle thinks the engine will start quickly enough. If you turn it so it's enabled (light off on the button) and it doesn't do the stop/start thing at lights and such - your ECU thinks something (probably battery condition) is bad enough that it doesn't want to risk it not restarting automatically when you expect it to.

TheCayenneKid

Great Advice! I will give that a try in the morning on my way to work. Your assumption is correct, I turned that silly feature off day one and never touched the button since. From the get-go I assumed that was a very taxing feature on battery/starter/alternator so it never entered my mind to troubleshoot with it.

Thanks!

PTEC

You can be sure the car will start if you replace your dead battery without coding the new battery to the vehicle. What this "coding" is really doing is telling the vehicle charging system that the car has a new battery and what size and type the new battery is. So in a sense no the coding does not NEED to be done. I dont know the exact ramifications of not coding the battery but if you dont, the charging system will working on the assumption you still have an old and aged battery installed. What, if any, affect this will really have, only time may tell. It may be nothing but Porsche is pretty specific on the fact that it SHOULD be done. YMMV.