Battery question?

I think the battery on the flat (based on my lack of general car knowledge or at least that what I think the problem is). I turned the key and waited for the oil measurement to come up and noticed that the air-con display was faint/normal "flickering". The PCM came on as normal as did all the warning lights as normal when turning the key one click. The remote unlock did not work (as usual after a few days now). I turned the key to ignite, but nothing happened other than, I think, sounded like the starter engine tried to turn (one turn at least) but not sure. All the warning lights where off, and no error message was displayed in the warnings. Tried a couple of times and the same each time. Don't think any of the dials turned at all... I then went on to turn on the parking lights, and only the left light was on but very faint. Turned on full, and the head lights come on which appeared ok. Now, the previous owner before me had had the car for 5 years and didn't drive it very much at all (20'000km/12'500 miles during the full period of ownership) and when I went to test drive the car back a year ago, the battery was flat then also and the garage owner did some quick charging so it could start again. I also noticed some time back that the remote unlocking would work after around 2 weeks of not using the car but this has come down to 5 days lately so it must be the battery right? I have not driven the car more than max 20 min combined over the last 5-6 weeks whereas I would go out for long drives during the weekends over the summer. Now, the currently battery is a Bosch S4 - 12V 580 406 074 740A (EN) 80Ah - S4 010 and I was wondering if I should swap it with a Bosch S5 - 12V 800A (EN) 85Ah - S5 010. Will this doing any good and I can see that the A and Ah is a bit higher in the S5 than the current S4? Is this a no-no? It doesn't necessarily have to be a Bosch and I thought I'd ask my Audi garage around the corner for either one based on your feedback in here... Thanks, and Happy New Year Added for my own sake: https://rennlist.com/forums/diy-subm...placement.html

S5 is 10kg heavyer and much larger. I'll doubt that it will fit. Allso bigger battery won't help, if you'r not driving the car enough to charge the battery. Try one of these, I'll bet that you won't be disappointed optima-batterien.eu

Thanks for the clarification on the type of battery speed rII . So you also recon it's the bat that's had it?

Buy the sears AGM no modifications required bolts right in. Diehard AGMG GP48 Item #22850748 for $174.99. as of 7-31-13 https://rennlist.com/forums/996-foru...t-battery.html I prefer AGM (Absorbed Glass Mat) Gel type batteries I replaced an Interstate MTP-H7 With a Braille 7548 AGM battery - direct replacement. Braille has raised prices $$$$ Braille AGM B7548 battery group 48 BCI Group: [?]Group 48 Length:10.9" (277mm) Width:6.8" (173mm) Height (without posts):7.5" (191mm) http://www.braillebattery.com/index....durance_series Battery sizes that fit 996 (group 49 will probably need a nut under the last, unthreaded, hole in the tray) Group Interstate number Dimensions L x W x H Posts 48 MTP-H6 10-15/16 x 6-7/8 x 7-1/5 Top 94R MTP-H7 12-3/8 x 6-7/8 x 7-1/5 Top 49 MTP-H8 13-15/16 x 6-7/8 x 7-1/5 Top

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Yes sound's like a dead battery. If your car sits long periods, lock it with the key. This way the computer goes to "hibenation" and saves power. Optima batteries are expensive, but worth the money IMO.

Kiitos speed rII . OK, so on the door locking front: 1. Straight forward when using the remote locking, everything locks, and no sound means all is fine. One "honk" and something is not closed (except for the partly open sunroof) which could be the luggage compartment, middle compartment in the cabin and/or the glove box. 2. After a few weeks of not using the car the remote unlock is switch off automatically. When opening the doors, I first turn the key counter-clockwise and then press the remote to de-activate the alarm. 3. When I then lock the door with the key (not the remote) the alarm is activated as I can see the red light blinking on the dash. So, how do I lock the car saving on the battery or is it option three (3) which is the way to go? I won't be driving much for the next three or so months... Thanks...

Thanks fpb111 , but won't help me much in central Europe I'm afraid ;-)

Bitte Frank. I might remember the locking wrog, owners manual only states that don't keep the key in the ignition when car is not used. No mention how to lock the car when stored. Well, new battery will hold the charge longer. So maybe that's all you need.

Might help with search knowing sizes that fit. Get a battery maintainer and use it to save the battery. http://www.batterymart.com/p-battery...-charger.html? Amazon.com: Porsche Battery Maintainer: Automotive Amazon.com: Porsche Battery Maintainer: Automotive Amazon.com: Porsche Dual Mode Battery Maintainer / Charger: Automotive Amazon.com: Porsche Dual Mode Battery Maintainer / Charger: Automotive

So, I got a new battery from the local VW garage and I'm going to fit this shortly. I have read up on a few things around this now and I'm a bit confused, as someone say's to remove the (+) first and others the (-) first before taking out the old battery (and fitting the new battery in reversal) Also, I read that some recommends to leave the ignition key in (turned one click) whereas others don't say anything about this? What is the correct way of doing all this?

Most would pull the negative terminal first. That way if you accidently hit a "grounded" metal part of the car with the wrench no sparks because you are working on the ground = negative side of the battery. Then when you go to the positive side the battery is disconnected so no sparks if your tool(s) hit metal on the car. Hook up the new battery positive 1st for the same reason. No opinion on leaving the key in. Maybe that helps to keep the alarm from getting excited while you hook up the battery? If you are pre 2003 you will probably need the radio code to get it working again.

You'll also need to reset the window limit so the power windows work as expected.

Thanks fpb111 for the heads up on which to remove first and I do also have the radio code at hand :-) 5CHN3LL (or anyone else) could you please clarify? What do you mean with I need to reset the window limit? I know the windows drop when oppenng the doors so does this mean I should keep the doors closed when chaning the battery? This is turning into a bit of a project ;-) so anyone else have any input before I get the wrench and beers out? Thanks as always for any pointers...

Once the battery is reinstalled, move each window all the way up, and then press the "up" part of first one and then the other window switch for 10 seconds each. Lift the door handle...if the window drops as it's supposed to so when you lift the handle, you've done it right.

Thanks for the tip 5CHN3LL ...

Optima batteries are mentioned here a couple of times. I have had two and wondered if others have experienced the same. I replaced a battery with the red top into a car that was sparingly used. The battery had run out a few times so started using a trickle charger with a cut off. The Optima worked ok for about six months but then had a hard time holding a charge again. This time it appeared the battery "burned out" (even with a cut off trickle). I finally replaced it with an interstate. I adopted a technique of adding a timer alternating on every other day. That has worked well for me for years. Recently I bought another Optima for another car, unfortunately the battery worked fine for months and now I have to hook a charger up even with driving it semi regularly. Not sure what the problem is.

Changed the battery, and no need to reset the windows, so happy as Larry... Now, the PCM asked for the code, entered it and all was accessable. Went for a drive, best one in a very long time, to the DIY store got back and the PCM again asked for the code. Is this normal, as I never have entered it before and now it asked for it twice OR is there a setting I need to change in the unit?

By PCM do you mean the radio head unit? If so, it is not normal to have to enter the code repeatedly. The code is stored until power to the unit is lost.

If you also have the Nav system then there is a code for that too beside the radio code. Usually it will ask you for both, one after the other before you can access to the PCM at all. That's what I had to do on my MY2000 C2 after a battery change.

Yes, by PCM I mean the radio head unit ;-) So, it asked for the PCM code but no the other code (which is also printed on the PCM card that came with the car) which I then think is for the GPS unit. When I fired up the car this morning only the usual GSM SIM code was requested and everything worked as it should. Having the unit swapped later this spring for new Kenwood module as the maps only are up to 2011...

So time for a new battery once again. I drive the car way too little... Question on the specs. I have three options as recommended by Bosch . 1) S4 Starter battery 12V 74Ah 680A 2) S5 Starter battery 12V 77Ah 780A 3) S5A Starter battery 12V 70Ah 760A So I'm wondering what I should go for? I know that when I bought the car it came with the Bosch S4 battery but I replaced it with a VW battery (based on ease) a few years ago as per the initial posting. I'm somehow leaning toeards the S5. This said, could someone who knows about this stuff explain what one should look after? I guess Bosch would not add any recommendations on their site if it had a fatal impact on the car...

H7 is what fits best in the 996....not sure what brands you have available in your location. Good info here: https://rennlist.com/forums/996-foru...formation.html

I run the H8 in my 996, if you have a Walmart in your country, get the Everstart Maxx battery, excellent reviews and 3 year full replacement with 2 more years prorated replacement.

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How did you bolt the hold down clamp? Did you have to modify the tray?

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The S5 has the better specs but not sure of your sizing conventions so you should check the LxWxH dimensions to make sure you get a good fit.

The U.S. market batteries recommended would be good choices, except those won't be available in your area. I'd suggest looking into a Varta battery, which is available in lead acid and AGM from 86-140 Euros. I've used them with success and they're generally regarded as one of the the best available in Europe.

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Size is the same for all. Again, I entered my vehicle info into the Bosch battery finder and these three, as mentioned, came up. Short of the long, I can use the S5 without any issues so I guess I'll go for that... Metric siye for the record: L:278mm x W:175mm x H:190mm

Thanks for the tip Mark I (Good to hear from you again btw) Varta seems to be quite easily available here as well. I found one Bosch battery dealer in North-Eastern Switzerland selling the Bosch S5 for CHF 189,- about the same in USD which is not too bad incl. P&P

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No modifications at all, there are 3 holes available for H6, 7 or 8 battery. when I bought the car, the mechanic had placed a H6 battery in the car, once warmed up and hot, start up were dragging big time, got quite a discount on the car because their mechanic had no idea what he was doing and owner was tired of the car not starting when hot and replacing the starter, new Y cables, no voltage drop testing, I put the H8 in there and no problems since then. After doing the research on batteries, I found that it was harder to locate a H7 battery, but plenty of H8 battery to be found.

Here's the battery group sizes. Bosch batteries also are sold by these size designations. Porsche recommends size 48. However I recently put the larger size 49 and it fits in the tray nicely. I had to hold it down by buying a washer/bolt and then installing it from underneath the tray so that the bracket can be held down with a wing nut. It looks professional and was simple to do. Battery group size 48 L/W/H= 12/7/7.5 Battery group size 49 15/7/7.25

Since your battery life seems to suffer from lack of regular driving, you also might consider either disconnecting it when parked for longer times, or investing in something like this: https://www.amazon.de/Cartrend-50264...ladeger%C3%A4t . Hope everything else is going well otherwise. Sch�ne Gr��e!

Also, one day a guy on the street asked me how to keep the porsche from going dead after 2-3 days. I mentioned I dont have many issues after upgrading the battery to the larger size. One suggestion I also have is to convert ALL your old style incandescent bulbs to LED. They arent as bright but they reduce the amp draw to a miniscule amount during those crucial times when you are starting the car and getting out after leaving it. i have much less problems with starting and leaving it sit for days. I left it at the airport for 6 days and it started like a charm without having to disconnect the battery.

Everybody keeps mentioning "S5, S6", etc... According to the Bosche website, each of those breaks out into many BCI sizes. You should focus on buying the model with the highest CCA rating in the BCI size that will fit (48 is the recommended). As I already mentioned, 49 will fit too, you just have to do a little work to make the hold down bracket work. It is 3 inches wider and in my experience, that makes a big difference. https://www.boschautoparts.com/docum...5-3e687cb69a2b

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Great to hear - usually the 3rd hole (for the H8 size) is not threaded and some folks report having to modify.

Frank, if you're installing the replacement battery yourself, also don't forget to not only reconnect the vent tube (passenger side of battery), but to plug off the hole on the opposite side.

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Thanks for the tip/reminder Mark I I already replaced some of the old bulbs with newer LED types (interior only) mainly because the older one gets the more light is needed to read the little print on speeding tickets

OK, got a new battery installed and all back to normal. Thanks again for all the replies. Very helpful in deed...