**HELP** Porsche 911 996 battery keeps dying :(

[Biggss2]

Hi All,

I purchased a 2003 Porsche 911 996 C4S Cab in the summer, all has been well until recently the battery died on me from what i read online its a common occurence, So i jump started the car with some leads (Leads on 1min max) car fired up, bought to temp, turned off- car worked fine allday.

Leave the car overnight, battery dead as a dodo.

Looking online, lots of people have this problem instead of finding a cure for it they buy a battery conditioner and leave the battery on charge whilst car not in use..

Im thinking it could be the alternator regulator, could possibly be alternator/starter cable reading some posts online..

the battery is a bosch s4 on it at the moment, any battery i put on the car, it just eats.

anyone know what battery voltage should read:

car off- no load.
car off, max load (lights, blower, ac, radio on etc)

car on- no load.
car on- max load.

Any porsche specialists, who would know in which direction to point me?

thanks in advance for your help guys

[caterpillar]

alternator regulator ypu may have the drainin... without any warrning... the doorlight svitch, the light in the glovebox... or if you does have a light in the engine compartment... and; the switch for the engine cooling fan; if the engine, are watercooled verson...( the fan are goin "on" modus, when its gets coulder...)

[Biggss2]

Cheers, I will check glovebox, and fan thats 2 things i havent checked, all other lights go off- boot, door puddle lights and engine compartment etc and yes it has happened without any warning, im hoping its the alternator regulator, got a guide on how to and luckily its (the alternator) right at the top of the engine..

thanks for your kind help.

[Biggss2]

any ideas, how to test alternator?

[simon20vq]

start car and go to battery and see if its getting 14 volts there or there abouts.

[Sleeper_Avant]

running should be minimum 14.2v and max 14.9

do a resistance check with the live and earth leads while they are unbolted as a cable may be failing.

where they bolt on must be clean from currosion etc as this makes a difference!

also check for a paracitic drain, i.e something using power while off.
this is done by removing a battery lead, bridge the battery and cable with a volt meter on Amp setting
if its arround 1amp you have a drain, pull fuses out one by one untill it drops off then you have your paracite

[Biggss2]

cheers, I know when im driving, i got a gauge on the dash that tells me Voltage goes to 14V. thats when im driving though.

Cant remember what it reads on idle.

[Biggss2]

And sleeper Avant, that would mean alot more to my brother than it does to me, I only know how to fill up and drive these things!!!

will start by pulling the plug on the alternator and then all the fuses fuses until anything is noticeable on the multimeter

Thanks for your kind help guys, Will keep you posted on how I get on, hopefully it is only the alternator regulator, and not the wiring that goes to it (the alternator loom)!!

Most likely get my brother to have a crack on it on saturday..

really appreciate it guys..

Thank you

[GazzaG60]

varta battery?

I remember my mates 996 battery going. that was a cronos c2s. had to get one from porka for to keep warranty. cost a fortune too

the porka batteries a tiny thing IIRC

[Sleeper_Avant]

have you had the battery checked?

may well just be a bad battery!

[ManiacuV6]

MEasure what the car drains from the battery with the engine off and door closed.

[martinws]

also check for a paracitic drain, i.e something using power while off.
this is done by removing a battery lead, bridge the battery and cable with a volt meter on Amp setting
if its arround 1amp you have a drain, pull fuses out one by one untill it drops off then you have your paracite

Do this^^^ It takes 5 minutes and will decide weather its a paracitic drain or just not charging(alternator possibly)


DO NOT START CAR WITH THE METER ATTACHED!

[Tonybolony]

Just asked my Lad, who was with **** Lovett in Cardiff for a few years, and he says to check the Navtrak. Apparently, they periodically draw excess current which can wipe the battery out overnight, but still work as normal.
Prob under bonnet, pull carpet back and on Passenger side (RHD) of bulkhead, or under Wiper Scuttle Panel, and disconnect multi-plug.

[Tonybolony]

Maybe I should have typed 'Richard Lovett' as the Bad Language Filter has removed the shortened version of Richard!!!!!!!!!!!!!!!!!!

[Biggss2]

Hello friends

Ok so had a chance to tinker with the Porsche.

It does have a drain of 1amp.

When I remove the fuse for the alarm, which also controls elec windows elec roof central locking inside lights with the fuse removed (15a) the drop goes to 500 milliamps.

So the parasitic drain lies somewhere within the above systems?

I've had the battery (Bosch s4) tested and it's fine..

I've for now disconnected the fuse for the aforementioned to see what happens and whether the battery drains

As always I welcome your thoughts/advice on my finding!

Thanks again for your kind help..

Also tony I'm not aware of navtrak and what it's for/ does?