ZuffenZeus

Maybe others on the 996 forum that have more knowledge about Porsche immobilizer systems can chime in here, but it's my understanding that Porsche created a "lock-out" mode to prevent people who would make duplicate laser cut keys from stealing your car. I'm afraid that once your car was locked, armed itself, and the battery went dead, it went into an immobilizer state that only can be unlocked by using a matched key code transmitted by your keyfob. Do you think your keyfob's problem could be something simple like the CR2032 battery went dead? Believe it or not, many people toss their keys when only a battery replacement was needed. Anyway, if the keyfob is definitely defective, the only other option would be to somehow get the car out of the garage and towed to a Porsche service center with the correct IPass systems.

But again, if you read Hammerthrow's situation, you'll find out this is a serious problem that even many in Porsche can't solve. They're are only a few people in the country with the knowledge to properly reprogram new security modules in Porsche 996 cars. At least that's what I gather. And so, if you connect 12V current to the lighter socket or to the fuse box, the alarm will sound, right? You see, even if you had a fully charged battery, the car won't allow you to start or open the trunk because of the lock-down mode. The only way to turn off the alarm and de-immobilize the car is to get that keyfob working again IMHO. If you can't, this will be a painful pill to shallow.

I hope you find a solution.

johnireland

Makes you happy you have one of the "old" modern Porsches. What happens in the new ones when parking brake button fails...or the start button fails...or the rear wheel steering program freezes in a right turn...or the nearest flatbed is 150 miles away...and its raining...hard...and a car full of tattoos keeps driving by...slowly...and looking at your wife?

ZuffenZeus

Some of my friends would answer that question regarding the wife like, "Do you want her? She's free!" or "She's for sale, and you're welcome to take up payments!"

Fab C

Chapter 3 - A New Hope ?

So, the emergency cable did marvels ! But new issues rise...

We were able to connect a donor battery on the engine, and for some reason that turned off the alarm. We jump started the car (had to call insurance service for a stronger battery) and off we go !

Now, when starting the car I had an "ABS failure" warning, and while driving I had a few "PSM failure" warnings (also calling the audio system to reboot). However, signs of the battery were alright afaik ? a bit above 12 when idle, jumping every few seconds to 14 (is that an issue ?). Solid 14 when driving.

Now, after 1 hour of driving I parked back home, turned it off and... the car won't start again !

I didn't try jump starting it again as I'd like to get your insights first.

What do you think ? Do I need to change my battery ?

dporto

Duh... Really? Either put the battery on a full "deep charge" and then test (not just start the car - which it may do, but it may not hold a charge) under load. Otherwise, just buy a new properly sized/spec' battery and be done with it. ***Also very important - get yourself a good trickle charger, and plug it in any time the car will be left I started for more than a week. Good luck

Carsly

batteries are cheap. if it was so drained as to not even open the hood it may have been permanently damaged. many electrical gremlins can be traced to a failed / failing battery. I'd replace with a new one (test at the shop before you buy, some batteries can sit for months) before starting to chase other issues which may or may not be real. I'd recommend an AGM battery and yes, a trickle charger / tender is a must on these cars.

ZuffenZeus

More like "Chapter 666 - The Force Went Flat!"

Seriously, you should NOT mess around with this issue and let the easy way out cloud common reasoning here. I've personally had this issue with other cars that have security systems similar to the 996 Carreras and you really don't want to mess around with low or almost dead batteries. Go to any auto parts stores (Pep Boys, Advanced Auto, etc.) and buy yourself a new battery.

Personally, I take more of a proactive approach instead of reactive approach when it comes to batteries. My battery was about 3 years old and still working fine, but since I'm taking a long trip in a few weeks, I didn't want to risk squeezing out a little more life in it and find myself stuck on the side of the road. Therefore, I used my "speed perks" 25% discount and purchased a top-end battery for only $160.00 out the door. That's a hell of a lot cheaper than having the car towed or serviced by Porsche.

And most importantly, once you get a working battery installed, I recommend you going to Porsche and see if they can repair your one and only Keyfob. Bite the bullet and purchase a new set of keys... you'll thank us in the long run. If anything I've learned about these cars, is that you should NEVER own one with just one keyfob. If you lose it, it will cost you an arm and leg... and maybe your ***** too. hahahaha.

Cheers!

ZuffenZeus

Once the car is stared, your voltage meter is reading the alternator. The figures you've listed have nothing to do with the battery's discharge capacity. Turn the car off, then turn the key to second position and that should give you a voltage reading, but again, if the battery can still read the proper voltage, but not have the necessary current to start the motor.

Fab C

Thanks guys, I guess I'll go with a new battery then. I'll call my local garage to see if they have some in stock.

Fab C

New battery installed, works like a charm so far... it might be an happy ending after all !

Now I'll look into those key fobs, sounds like it could be the beginning of a whole new saga ;-)

Thanks for your help, cheers~

ZuffenZeus

That would be the first thing I'd do. If you can't find a working keyfob, it's going to cost you a lot of money to fix. Didn't you say you had one Keyfob, but it wasn't working? If so, I'd take to Porsche and see if they can read the code for it or at least hook your car up to the iPass system and see they can make you a new set of working keys.

But regardless, keep a fresh working battery in your car at all times! Hope you have a wonderful summer!

Fab C

Yes, I do have one and brought it there already before the car was immobilized. Porsche guys said it was just the key battery, changed it, and it worked... for about 20 minutes. Back home it was already dead.

No idea what the real issue is, but I know for sure the official service center isn't the most skilled around. I'll try again soon.