PiB993

Dead in the water - anybody?

Any other problems I might be in store for besides radio code and readiness codes? I'm not too worried about those yet.

Without access to an outlet or sunlight (garaged) any suggestions on ways to preserve my battery easily without driving more? Would a kill switch work or mounting an additional battery while it's sitting help?

Mike J

If the battery cycled low its just the radio codes and possibly the ECU readiness. The rest will work fine once you replace the battery.

Remember that lead-acid batteries do not like to be deep cycled, especially those in cars. So while the battery at times appears to be all good after a deep discharge, it will have less capacity and may cause issues if a lot of draw is needed, say in the winter. In your case its not a problem since it's clearly failed.

I would not buy an Optima battery every again - went through a few, they fail way too fast, so I have concluded they are crap. I have a supplier here were I can get slightly marked lead-acid batteries of the correct size, brand new with warranty, for about $50 - so I just use those.

If the alarm goes off when you unlock it, get to the trunk and disconnect the battery - you will need a 13mm wrench or a crescent wrench, take off the negative terminal (the one with the braided wire - negative terminal and farthest away from you when you are standing in front of the car).

Yes, a kill switch that totally disconnects the battery will help since the car draws a low level of current when its off - and that over the long term drains the battery. However, if you do this, everytime you turn the car back on, you will need to reprogram the radio. You can also have a second batter in parallel to the one in the car (using jumpers, etc) -> but that will still drain over the long term.

If the car is really sitting for a long time, pull the battery out of the car and bring it inside, and put a maintainer on it. That is the easiest on the battery.

Cheers,

Mike

PiB993

Thanks!

Piece of cake then. I'm turning this into a bigger deal then necessary. I just hope I don't have to do that ignition key turning routine! When i read the manual it mentioned some code (4 digit?) unique to the car which I don't have afaik!

Can Porsche dealer provide me with my radio code if mine has been lost by previous owners? In a car like this radio isn't what I'm there for to be sure!

I'd like a sealed battery. The whole Rennline Odyssey drycell battery/bracket and kill switch is intriguing but totally not worth it. I might be fooling myself into one of the Braille AGM batteries - if they fit! I try to drive my car once a month just with work travail, etc not always possible. Any type of battery that works better for periods of sitting with this car than others?

PiB993

FWIW I just got an Interstate Battery (really not that cheap at $170 with CA taxes) out of fears I may have an issue with my alarm being erratic and that perhaps that killed the battery. And as far as my alarm after pulling a dead battery nooooo problems. All my fobs still work too. Unfortunately, there was a little acid corrosion from the old battery (no mat installed) :-< I have to admit, changing a battery in a P-car for the first time let alone a 993 is a little different.

foxj0001

+1 on the Ctek charger
I left my V1 plugged in and turned on in my '96tt for what must have been a week in the garage (duh), power locks still worked to get in with fob but not enough voltage left to turn the starter motor.
Plugged in the Ctek and in a few hours had the battery up enough to start the car. I did have to reset the radio code. After making sure all systems seemed ok I turned the car off and plugged the Ctek back in overnight. In the morning the Ctek was off (standby mode), indicating charging was complete.
I use the Ctek for my 997.2 GTS in the winter, too. As others have said, identical to the P-branded unit but for the logo and the price.
Jonathan

foxj0001

P.s.
Needed to pull ECU for repair/revision at one point and disconnected the battery before pulling the unit to be on the safe side.
Upon reinstall of the ECU I reconnected the battery and car started right up no issues, but of course I did need to reset the battery code. BTW if you cannot locate your radio code card that should be with the manual and the rest of the car's papers, the code is also printed on a plate affixed to the panel just above the ashtray when in the open position (what a great security feature!).
As an avid boater I have had to deal with a variety of 12 volt issues rarely encountered in the non-marine environment, including various winter storage strategies. If fully charged, then disconnected and stored inside in a heated building, a reasonably aged and well-maintained lead-acid battery should hold its charge well and be able to start the car promptly when reconnected (warm). Cranking amperage is very temperature dependent, less efficient the colder the battery. Interestingly, the inverse holds true for charging - more efficient for a cooler battery.
Jonathan

foxj0001

Re last post, meant radio code not battery code!

PiB993

A ha! Thanks fox for that tid bit of information. It will make my life much easier. I'm still going to comb through all my documents for any articles I may not have noticed the first time.

I really would like to find a totally sealed battery that is comparable to the Interstate 91 battery. With the radio code handy maybe a kill switch on the battery a la rennline/odyssey to semi-preserve the battery in lieu of charger/maintainer is possible. Should probably save that money for a Duratec reader instead but upgrade-itis/top trumps/guinea pig Still fearful of the alarm code. I need to read the manual to determine what circumstances causes it to become necessary - extended no battery connection?