Battery replacement

Hi everyone, My battery is starting to slow down a bit so I need to replace it. The one in there is a 68 amp, but Porsche Cambridge says I should have an 80 amp, and online I've also seen 72 amp mentioned. Is it 80 amp, and if so is there a good place to get them at a reasonable price? My car is a 996 2001 C2 Also, does anyone know of a way of changing batteries over without losing the power (radio code)? Cheers, Alex

The best I found was Euro carparts who do a Bosh Silver Calcium which is around 95 GBP inc VAT. This is for an 80 amp which the later ones do need.

My local independent fitted a new battery for me in July. Not sure of the specification other than that it was an improvement at a cost of £75 all in. If you do it yourself, get some ear defenders. Once the battery is disconnected the alarm sounds very LOUD, particularly with the bonnet up. Can't help you on the radio code, I had to re-enter mine.

Hi Alex. Don't think that I live near you so can't advise on where to buy but just make sure that you get the same amp/hour rating on the new one. When you change the battery you need to put your key in the ignition and turn it to the point just before the engine turns over. Leave the key in this position - it prevents the alarm from going off and you needing new eardrums. Get out of the car. Don't shut the door as the window will go up when you do and you won't be able to get back into the car until you've put the new battery on - and you might get delayed by unforeseen tech problems. Lift the bonnet and use a 10mm open-end/ring to disconnect the battery. Take negative terminal off first. Undo the battery retaining clamp which holds the thing down so that it doesn't move about (can't remember the size but you'll need a socket (?16/17mm?) with an extension bar on it to undo this bolt. Take out old battery. Put new one in - watch your back now! Put the positive terminal on first then the negative. Everything will spring into life when you do this - as you've left the ignition on. Replace retaining bolt and battery cover. You can now turn the ignition off - or go for a spin. My car is a 2003 - I didn't have to re-enter my radio code but I'm not sure about yours, sorry. Hope this helps. I had to do mine recently and only discovered all this after a lot of trial and error - and sore eardrums! It's an easy job and very satisfying when you hear your engine spin over! Adrian.

Great post Adrian we should get this put up as a FAQ![ ]

There is a bit in the Alarm Issues & Tips FAQ. I would always disconnect the negative (earth) first. That way, if the spanner touches the body it won't go bang. Similarly, I would connect it last, for the same reason.

Cheers Rod! Richard - I thought that I had that the wrong way 'round - sorry guys! I'll edit now. Adrian.

The guys at PCT changed my battery for me- They connected one of those portable jump-start thingies (a sort of rechargeable battery unit) to the car's power terminals, then switched the batteries over. That way the car never noticed that it was batteryless... And I can confirm from an earlier occasion that the alarm is outrageously, ear-splittingly loud.[ ]

Job done - it's in the 996 Technical Articles section. I have to say that I went completely OTT with this, and put some additional battery maintenance tips in. Thanks go to Adrian for his tips, and initiating the DIY.

Looks excellent![ ]

Hi Thanks a lot for all that advice, that really will be useful when I change them over. I can order an 80 amp battery through a mates company at trade price but he's asked me for a make and model as obviously they're all different sizes, is there a particular make I can tell him? Thanks, Alex

Hi Alex. Anything - as long as it's not made by Porsche!!!!!! IMHO Varta or anything German (except Porsche) usually do well. Ade.

With your ignition turned off and the key out, check to see if the cig lighter socket still works. If it does, then simply plug in a charger/conditioner (Optimate type) type to the lighter socket and leave it on charge for a while. I charge mine when not in use for a few days.

Hi Ian. Taking on board what you've said - word for word - I'm afraid that your symptoms point more to a charging problem rather than a battery one, especially if you keep it topped up when not in use. It sounds like you disconnected the charger and started the car which then just started to sap the battery of its juice. I hope that I'm proved wrong but I have to tell you that I had the shock of my life when I had exactly the same symptoms and ended up replacing my alternator - at 19K miles!!!!![ ] I would drive to an electrical motor factors ASAP and ask them to run a quick output test on the alternator for you. That'll pretty much decide what's going on for you. When you start the car, what is the voltmeter reading? I would strongly advise that you go down the motor factor route first as an OPC will probably tell you that you need a new battery and a new alternator. And a new engine. Incidentally, my new Porsche alternator cost me circa £280 from my Indi. OPC wanted circa £600. Just thought I'd point that small detail out to you. Let us know how you get on. Adrian.

Also check out the battery change DIY here: http://www.porscheclubgbforum.com/tm.asp?m=331718

If it is the alternator - chance are its the diode pack. This can be done by any reputable auto electrial specialist from about £40. Thats waht I was quoted last year and £100 to recon. Here in Preston it was Ribbledale Autos Those prices are of course if you take the alternator off yourself.

Sounds like a very good reason to buy the same battery.

I’ve just bought a HAL 110 Lifetime battery from Halfords cost £145. I also don’t do many miles so will be interested to see how it goes.

I checked and confirmed that mine sounds the same. Bosch S4 010 740A (EN) 80Ah. That was the largest battery capacity I could get for the 996 as far as I know which is why I went for that. Out of interest, Costco used to stock those and had very reasonable prices. I think all all of these standard lead acid batteries will suffer if not in a car that is regularly used or on a good charger/conditioner (CTEK). Over 10 years is pretty good going at around £10 a year or less If the battery was £100. I'm sure the Costco price was closer to £70 which makes it a steal.

After not running mine for 5 maybe 6 weeks, and on a CTEK, mine was dead last week. It was a Varta but i have no idea how long it'd been in the car before I got it in Aug 17. Longest it hadnt been run, before I got the CTEK, was 3 weeks, and it JUST started. I hope I dont have a faulty trickle charget. AA van to restart me had a YUASA with a 5 year warranty that I bought for 163. Maybe wish Id gone to a store now/online, but, I wanted to be up and running last week

Cheers all. Still not made my mind up. Car is used very little at the moment whereas before it was used daily. Will check Costco to see what they have but am also considering the Yuasa lifetime battery.

Use a CTEC an absolute must (AS long as it WORKS) Ive just bought a Bosche Platinum as I didn't know how long mine was on the car 90.00 with 5 year warranty

Check out an earlier post of mine: https://www.porscheclubgb.com/forum/tm.aspx?m=982746#982851 hth

@JH Motorsport S5 010 800 is the biggest and most CCA

I've got a CTEK MXS 5.0 charger that I bought for my CR-Z as the main battery is only a very small capacity battery (as its got a huge 100V battery under the boot floor) and I was only going to be using it once a month or so, rendering it flat by the time I wanted to use it. I've brought batteries back from 'the dead' with a couple of chargers. A deep sulfated battery on my Clio 172 which was brought back to life by my Optimate III SP. (and consequently didn't need to replace it for the next 3 years) And the CRZ battery and the Type R battery kept on their lifelines by the CTEK. In the year that I've had the Porsche, I've actually only gone a couple of times where its gone around 7 days without moving. I think I've hooked up the CTEK to it two or three times max. For the £70 it cost me, its cheaper (and less hassle) than buying a new battery, and of course it can always be used on the other car, and the next cars I buy.

Have you seen when a battery explodes? Some batteries are best left dead, just saying be careful.

I've only used the Optimate and CTEK trickle/maintenance chargers to charge them. I'll bear your point in mind thanks thirteeneast. Best bet is to make sure the battery doesn't run down too much which means keeping the car running regularly. I generally use it 2-3 times a week and it ends up doing a decent run each time

When these cars were new you couldn't get insurance without a tracker fitted, most of which are poorly fitted and consume ridiculous amounts of power "hence the battery drain on a lot of people's cars". My advice to anyone who thinks they have quite a current drain would be to look for an old tracker installed and get rid of it. Any battery should be load tested and if it can't hold to spec get rid of. Any car used a couple of times a week shouldn't really need to be kept on charge. Most I've seen are poorly fitted behind the head unit which of course is the first place anyone would look anyway.