Flat battery again

Hi I had a flat battery the other day so placed the old charger on., but after removing charger I have now noticed that the headlight switch surround seem to always be illuminated also my wipers can be operated with out having keys in the ignition. Only owned the car for a few months and all has been great untill flat battery. Was wondering if all is normal or I have an electrical gremlin which may have caused flat battery. Thanks Jon.

Hi Jon Beyond me but DeMort will probably come along with the answer!

Replace the switch part of the ignition switch (i.e. not the lock).

:yeah: For me i would replace the entire ignition lock .. there have been a few problems mentioned on here about the wrong or a different electric block just being replaced .

Hi just liked through my paperwork and the car had a new ignition switch in June this year, is it possible that it's failed already.

Aghhh .. this is more complicated then .. Wipers cant work without a key in the ignition and switched on , again illumination cant happen .. if the ignition switch has been replaced (and this is the main cause of things like this ) then its a garage job im afraid . If your handy with a voltmeter then the wiring diagrams can be found here .. along with the rest of the workshop manuals .. http://www.911uk.com/viewtopic.php?t=83491 Illumination could be related to a faulty headlight switch but not the wiper fault . Gut feeling is a sticking relay but im afraid its a case of out with the meter and start testing things . The car locks ok on the fob i take it ?

Hi thanks for reply, everything works great lock and unlocks with the fob drove it the other day all good then it sat on my drive for two days, When I got home from work i heard the alarm going off which unfortunately run battery flat, I tried charging battery through the fuse box terminal and door post for earth as couldn't open bonnet. Later managed to connect othe car battery via jump leads to open bonnet and charged battery over night, I haven't driven car since, as was going out armed with multimeter at weekend when I have more time and daylight.

If the car locks ok on the fob then the car knows the ignition key has been removed .. ignition lock if not .. we are basically into a fault traceing mission atm from what i can see . With out being able to see the car then this is pretty much the hardest problem to find . If you are ok with wiring diagrams and volt meters and want to tackle this your self then im happy to assist . You may after all just have a battery discharge .. wishfull thinking on my part i feel Im only here from 7-9 pm btw .

De mort - do you use an oscilloscope in your day job on problems like this or just a voltmeter? I'm just curiois as I have been reading up on them and watching YouTube videos. If I had the money, I would buy my own pico scope. @jon - If you are in need of professional help, find a guy like Frank Massey http://www.ads-automotive.co.uk/project/vehicle-diagnostic-experts/ I don't know anyhthong about him apart from what I have seen and read online, but If I was anywhere near Preston and I had a similar problem where the solution wasn't obvious, I'd take it to him.

Young man !!!! Asking me about tools is the same as phoneing me and having to listen to me waffle on for hours about the fault or Porsche in general :floor: Long post coming i feel .. Pico scope .. excellent bit of kit but not cheap .. you tend to start at about 1K then go up from there .. There are several things you would use a scope for depending on the age of the car .. If we are talking air cooled then pretty much only for a non start and to check the CPS sensor which to be fair there are other ways of checking so not really usefull . When we come to the later cars though .. 997 onwards then some items are not just a 12V on / off they use something called a PWM signal .. this is a varing voltage / ampage so kinda like a throttle but with electricity .. the more you give it the faster the item will run . Its also between 20 - 80 % as below or above that indicates a short on the wiring .. ie short to positive = 12 volts constant so a flat line and nothing is an open circuit . I have to admit though i dont use a scope very often , most times i have other ways of checking but the newer the car then the more need to have and use a scope . Im not sure for a Diy you would find much use for it ..but if like me you like to collect tools then go for it Now then .. a scope is not really of any use when traceing things like battery faults / battery discharge or just general A to B circuits . For this its a volt meter .. now to give you some idea .. i actually have 5 voltmeters .. x1 is an analog meter so its a needle that moves .. this is mainly for the older cars that have a fault code read out thats a blink code .. a digital meter is a bit hard to use for this but an analog is perfect . Ok the other 4 .. one is sentimental and not really used (it was £500 when i bought it and i cant throw it away after 20 years ! ) .. anyways thats a Fluke meter .. some of the best in the business to be honest . I have a cheap £20 one but it can take 20 amps which is why i got it .. nothing worse than checking for a drain and the alarm trips .. it will blow the normal 10 amp fuse in meters and that tends to be about £15 per fuse .. i have to pay for that so you see the problem !!! My latest is a snap on one .. not cheap but things like Hz and duty cycle can be usefull .. think PWM .. duty cycle I also spent a good chunk of money on an attachment for it .. i can now check amps upto 30 !! bear in mind if a Cayenne alarm trips its about 26 amps so for these cars its a god send . Anyways .. to the point .. if im looking for a battery discharge i use an amp hound .. A scope is of no use on this problem. https://www.youtube.com/watch?v=pM5qV6ge2vA Very easy to identify which fuse the drain is on useing this .. then its onto the wiring diagrams to nail it down further . Its also excellent at finding blown fuses so some times i just use it for that and quickly run over the fuseboard as a fast check .. no need to search diagrams and waste time as this is quicker . This is kinda my secret weapon at work as no one else has one and it makes life SOO much easier Us Mechanics have to buy our own tools .. so not every one will invest to a great degree ... my kit has to be in the region of £20K by now !

Hi back again. I have been to the porsche specialist this morning and he is unfortunately booked up until February. He did check my battery and said due to windscreen wipers being able to work with no ignition key in was strange and recommended a new switch, which is a cheap start and I can carry out the work myself, but when I disconnected the earth from the battery the alarm went off even though I had the key with ignition on (dash lights on). Is this normal for the alarm to activate and if so should it go off after a few seconds as I don't know if it's safe to change ignition switch while the battery is fully connected or if it's going to set off the alarm again. Anymore advice would be great. I have left the car on trickle charge but unable to lock car as extension lead runs to bonnet.

I run the extension through the top of the bonnet by the wipers. You can close and lock it then. btw. I'm following with interest as I have a similar problem. But mine is ok one week but not the next. I have an AmpHound or order. If I come up with anything I'll let you know.

Thanks for the tip, also just looked up amp hound looks like a great piece of kit.

Interesting that the alarm went off - it shouldn't if all is well. I'd definitely be checking that the ignition switch behaves as it ought to.

Hi guys I have a 2002 996 is this the correct switch part number 4A0905849B and are there any recommendations as I have seen some for around £10-£15 pounds thought that sounds too cheap, not that I'm moaning.