Battery flat despite fitting a new Varta 3 months ago? Help.

Hi Guys. I wonder if this is a common problem......Bought a recommended Varta (read thread on 911uk) for my baby 3 months ago following 3 flat battery episodes. All was well until yesterday went the car did not turn over. Battery flat again! Nice chap from RAC prestige came round to help. He knows my name now! He says it is because of the short journeys I do. He checked the vehicle over to ensure nothing was draining the battery. I think I should buy a charger with an instant start facility. Which one should I go for? Not too expensive please? And yes Zoe Hardman is fit. Thank you in advance.

How often you use your car ? It might be worth getting a trickle charger (either mains or solar depending where you park your car) Also have you checkd if anything is draining the battery ?

What is a trickle charger? The RAC checked if there were any components draining the battery - nothing was found to interfere. I usually use the car everyday ~10miles commute to an NHS hospital car park where it reluctantly stays outside till i go home. It then lives in the garage overnight. Thats if I am not working nights. I left the car alone for 36 hours last time and the battery drained? Not sure what is going on. Will buy a charger from Halfords this week using topcashback! Many thanks for the reply.

The exact same thing happened to me. I would get the alternator checked.

Trickle charger is basically charging the battery slowly while the car is switched off so as to compensate for the current that the alarm for example is using In your cae with the usage you have then you should not have had that problem so I will agree witht he comment from andy to have your alternator checked To have a flat battery (check other posts) the car needs to stay stationary for 3+ weeks

a drained battery is not uncommon in 996s....could be your alternator...I have the problem after 7 days and I think its down to my tracker. i put it on trickle charge if i am leaving the car not driven for very long. I have only used the trickle charger once :lol:

A 10 mile a day run each day should not leave you with a flat battery. There should be no reason to use a trickle charger. Check voltage output. Connect a volt meter across your battery terminals. This should read 12v + Start the car this should pulse(smoothly) if it jumps up and lowers irratically you have rectification problem with in your alternator, as the revs are increased so should the volts to 13.5 plus. Apply load to the car(AC,Lights heated screen) the voltage should still read 13v plus as the alternator deals with the load.You will here the engine idle lower as the alternator pulls in to load status. No idle change? no alternator output. Rev the car again this should see the voltage stable at 13v plus. Try the car in the dark on idle with the lights on against a wall or in the garage. Rev the car and the lights should brighten smoothly and the volt meter rise. If all this does not happen then alternator or connection to the alternator is at fault. If all is well then have an motor electrician check out for static load when the car is parked with the alarm on. This sounds like a miss diagnosis of a failed battery in the outset. You have a problem. A trickle charger will only mask the issue. On a long run with the alternator loaded up you are going to grind to a dark and lonely stop. 3 days idle in the garage should not leave you with a flat battery. Trickle charger?Save your money!!!

I left my car for 6 weeks over Christmas/New Year and until the worst of the salting was over. I regularly leave it undriven for two or three weeks with work travel and the fact I only drive it weekends. It has never dropped more than 1-2 volts even though it is left alarmed with a tracker running. Certainly 36 hours indicates either the battery is shot (unlikely given newness of battery), if the alternator was shot then it would never charge sufficiently, to discharge without use in that time must mean a drain somewhere. If your battery is an 80 Ah capacity and it discharges completely in 36 hours, that means a 2.2 Amp drain (or 25 watt drain at 12v).

Have a good read of this thread . In your case it does sound like an abnormal drain. To accurately test this you need a decent auto electrician (I use No.5 Garage) with the Bosch device thingy that clamps onto the battery cable and measures drain once you have locked and alarmed the car. Things that might be draining it: a tracker whose battery is dead, an old car telephone which is hidden under your seat or elsewhere that you dont know about, got any other non standard gizmos?, in older 996's some alarm bits are in the front boot and can corrode causing a drain. Unfortunately there are loads of things that could be causing the drain. Dont trust a normal mechanic, especially not OPC, or RAC. Get a decent auto electrician to investigate. Good luck.

If interested I may sell my OEM Porsche trickle - charger. It plugs into the cigar lighter, unsure how long the lead is, I would think a good 10 metres. I have never used it.

+1. Probably incorrect diagnosis by RAC, you need a specialist, will save you a lot of grief in the long run. If you have the skills and the meters you can do this yourself. do not trust OPC, you need an electrical engineer. Ray :thumb:

Many thanks for the posts chaps. I have booked the car into PCT next week. Hopefully it should be ok till then. I shall print out the numerous diagnostic suggestions to help them. I have have good experiences with PCT so hopefully it should not be a problem for them. They are honest boys. Also booked it in to rectify some rattles coming from my door airbags and uncharacteristic rattles from the Targa roof? I can tolerate a few rattles but these noises take the urine. Not even silicone spray - the targa owners best friend can solve them. I thought turning up the Avic D3 would make them go away.........£££££

996 Battery - short journeys not a problem Just to confirm some of the previous posts, I do about 6 miles a day on 3/4 days a week plus a small amount of weekend motoring in a 996 C4Tip . I have had 3/4 years of driving these distances and no battery drain problem at all. Just replaced the Varta E11 (thought it was coming to end of life) for one of the new silver range (recommended specifically on the Varta website) and the turnover speed is smoother but the old one did a good job over its life just thought I'd post to say that this is obviously not an endemic problem

I think "Dr Adeymars" has the correct diagnosis. When I started the car, it did pulse smoothly initially but then it lowered suddenly without me applying load to the car. I did not have a voltmeter unfortuntely. Also when I switched the litronics on in the garage and rev'ed the engine, the lights did not brighten smoothly (i think). It does sound like the alternator to me. Many thanks to the good Dr. Much appreciated indeed. All I need to do now is sort out my offside shock absorber which is "seriously leaking fluid" according to my MOT failure report! Its a damn good thing, the car is going into PCT on Wednesday. Many £s. Still have to retofit cruise control courtesy of Wrightune but that can wait till my Birthday. An expensive week which saw me buy hospitality tickets for the freak show that is Michael Jackson at the O2 (4 rows from the front central block - within touching distance of him and ABCD-listers). For the moaning wife who is annoying me. I want to sell them and the wife. I see ebay selling them for £10,000-£17,000/pair. I will listen to sensible offers from this trusted 911uk.com community. It is for a Sat night next year (Jan 9) I am saving for a turbo-bodied PDK (C4S or Targa 4S maybe TT)!

I hope the real issue is found on Wednesday for you. Battery and alternator are often changed by misstake due to poor diagnosis(not specific to Porsche) It is very easy to see if ether are at fault. Very dfficult to find a drain though. A digital multimeter for Argos under £20 would have recorded the voltage output accutately enough. Sounds as if you have your finger on it though. And......... Sell SELL SELL The tickets. Who's bad! ance-Tap: