I pulled a bonehead move..................left the car for a few weeks without the battery tender on and came back to a dead battery.
Stupidly, I stuck the key in the ignition.....................now it can't come out until I get the battery charged. I would jump it, but my wife is out with the other car. I put the trickle charger on for grins to see if this could do the trick..........what's happening now is every 10 secs or so the dash lights etc. flicker on for a few secs then die out. I'm wondering if I can leave it for a few hours and if this will eventually do the trick, or if there's no alternative but to get a jump, or replace the battery. I wish I could get the key out because then the dash lights wouldn't keep trying to come on and mess with the charging process.
Any advice/thoughts appreciated.

 

Try to unlock hood while you got charger connected, if it opens disconnect ground from battery and charge battery directly.

 

There is a key removal tool on the inside of the fuse box lid, and a hole in the ignition lock area for insertion to remove key. Instructions in manual

 

Just last week I had the same predicament when I left the key in the ignition. You will need to get into the fuse box and then hook up jumper cable to a fitting in the fuse box panel (instructions in owner's manual) in order to get enough juice to open the front trunk . That will allow access to the battery for recharging. My mechanic recommended NOT to get a jump since this puts undue stress on the alternator. So I hooked up a battery charger to the battery while sitting in the garage. When I had enough charge to start the car, I drove to my mechanic where he charged the battery overnight on a more heavy duty charger in the shop. Be sure to remove the key from the ignition as this causes an inordinate drain on the battery. Even though my ignition was turned off and the car had a trickle charger on it, the car had gone dead from the key being left in ignition. When battery died, I could not remove key from ignition.

 

Car would not start Saturday night after trip to home depot. Came out to flashing lights but no horn. Thought maybe somebody set off the alarm. Call Porsche RSA and they came out and started it with a portable pack. Went home and plugged in the battery maintainer and 2 days later the light is on and still won't crank. I am sure at the very least I need a new battery. The car is an 09 and still under warranty. Do I just replace the battery myself or take it to the dealer in case there is an underlying cause?

 

Try charging the battery with real charger.
Had a similar issue, and the maintainer did nothing.
Thought I would need a new battery until I charged the battery and tested outside of the car.

 

Bought the car used in October (sat on the lot approx 3+months)and have had some low voltage issues in the past thus the maintainer. If I am going to take the battery out why not just put new battery back in? Read I could get a better one at Walmart.
Thanks

 

You can never go wrong with a new battery.
Any battery shop will be happy to put your current battery on a load tester. If it tests OK, then no need to replace.

Low voltage issues can be cable related.

 

Had a battery die recently (refused to hold a charge) and did a little digging. I was told porsche batteries are "rubbish" and you're better off just dropping in an interstate battery from walmart, which should come with a 3yr+ warranty?

 

Don't forget to lock your car when its parked in your garage at nite. Battery issues will all but disappear as it puts the car to sleep and not ready and waiting.

 

Changed out battery! PASM error cleared! PDK shifts so much smoother with new battery. Did not realize how jerky the car had gotten until now. Will take old battery to autozone to confirm dead cell. Did not consider a correlation between a dying battery and the PDK.
Took like 10 minutes.

 

I think the PDK correlation is due to the battery being dead/replaced, and the PDK ECU is in "learning" mode, as it always is, but with a blank slate.

 

I don't know, but I really hated the 1st to 2nd shift first time out of the garage for the day. Would hold 1st too long at low mph then jerk into second. Only did this on 1st run of the day. This issue is completely gone now. Thought I might need to go to the dealer for some PDK update but not anymore.

 

Porsches need to be driven approximately 12 miles without turning off the ignition.
The exotic electrical systems drain the battery immensely.
You can't drive 2 miles and turn off the car, multiple times, and expect a trickle charger to completely rectify the situation.
Trickle chargers definitely do prolong the life of the batter, and the Porsche one is great, although just know that it is manufactured by C-TEK and you can order the same one at Amazon.com for half the cost of what Porsche sells it for, FYI>
Unless you only are doing long distance drives ( greater than 12 miles) each time you drive the Porsche, expect to replace the battery every year or so.
At $400 a pop at the dealer, this can be expensive.
If you are still under warranty, I recommend still going to the dealer because you don't want an electrical problem causing an expensive fix that the dealer refuses to honor because you voided the warranty (by putting non-OEM battery in).
Having said all that, now that my Porsche is out of warranty, I go to the Autozone and get the battery for one third of the cost at the dealer.
Good luck.

 

I think that once one of these new batteries goes dead, it can not be brought back to "full life", something to do with the battery chemistry...