Porsche 996 C4s 2004 Flat Battery - Page 1 - Porsche General - PistonHeads UK

My 996 is dead, I’ve tried jump start via the terminal in the footwelll fuse box panel, I can here clicking noises coming from glove box area, no lights on dash… I have a Clifford 5 alarm which I suspect could be the problem.. can’t access my bonnet or boot, tried the buttons to release either but no joy.. any help would be greatly appreciated

Fairly certain you can access a manual release cable behind one of the headlights, it’s been a while though so may have it wrong!

Is the battery dead or has the car gone to sleep. I leave my 996 locked but plugged into a Ctek trickle charger. It goes to sleep. I have to manually open the drivers door to wake up the remote locking which sometimes sets off the alarm. Have you tried opening the drivers door with your key?

The terminal in the fuse box is for energising the electrics to open the bonnet / engine lid not jump starting it. Hopefully you’ve not fried the electrics! I’d check the fuses associated with the bonnet release and then try attaching a battery to the fuse box post as per the manual and see if the bonnet opens.

I tried a booster just give that trickle to press the bonnet button but it’s not working, there’s no power at all and no lights.. I can turn the key but that’s all.. I can hear a clicking noises constant near the glove box… could it be the Clifford alarm that’s not letting the car start…

Rich G Rk54 said: I tried a booster just give that trickle to press the bonnet button but it’s not working, there’s no power at all and no lights.. I can turn the key but that’s all.. I can hear a clicking noises constant near the glove box… could it be the Clifford alarm that’s not letting the car start… Do yourself a favour and get a multimeter so you can measure the voltage with the charger disconnected. If the main battery is extremely low, you'll need to allow some time of it being on charge before it may revive. It may well be end of live/unrecoverable if deeply discharged.

Depends if the clifford immobilises any circuits? Do you think the battery has fully discharged / died? Did you try the bonnet release first? (You dont normally need the key in the ignition for this) I don’t know enough about the circuitry to know for sure you’ve damaged anything trying to start with power connected to the fuse box post. There is a possibility its tried to pull several hundred amps via the permanent live circuits? My advice is to get the bonnet (or engine lid) open by other means - have a root around the openings in the off side of the bumper - rad air intake holes, for a cable looking bicycle brake cable. You may have to remove the wheel arch lining and look

Thank you will try manual release some how…thanks for the advice so far always appreciated!! I’ve only had the car 3 days been using everyday .. just went one morning and nothing

Try the emergency release terminal again; connect +ve to the red tag in the fuse board, -ve to the door check strap, then press the front lid release on the key at the same time as pulling the release switch in the sill - generally works……

I’ll try tomorrow and check back with you guys, thanks again for now. Kindest regards Richard

Ahem... https://youtu.be/u0EpWBV3be4 Same as on 996

Sorted , the key fob has less voltage than that of the electronic bonnet opener button, pressed it a few times whilst the booster was connected to the fuse box red terminal for battery and negative to door hinge. Battery is fine just didn’t get enough charge on a drive.. .. it’s on trickle charge now.. thanks again for all your kind help and wishing you all well! Kindest regards Richard .. 🏎

I totally agree with you.. just like anything if you don’t have the correct tools then no point starting the job.

shantybeater said: Fairly certain you can access a manual release cable behind one of the headlights, it’s been a while though so may have it wrong! had to do that last summer - take front wheel off and rip really hard at a cable you can't see (hope that you have the correct one) and then the front lock releases

The release cable is on the drivers wheel arch but the arch needs to be taken off for access.. thank goodness this option was not necessary..

Rich G Rk54 said: Sorted , the key fob has less voltage than that of the electronic bonnet opener button, pressed it a few times whilst the booster was connected to the fuse box red terminal for battery and negative to door hinge. Battery is fine just didn’t get enough charge on a drive.. .. it’s on trickle charge now.. thanks again for all your kind help and wishing you all well! Kindest regards Richard .. ?? Pleased you are sorted. There sometimes seems to be some confusion between boosters, battery (trickle) chargers and battery conditioners (Ctek) which come with various outputs. A car booster-starter (as I regard it) is a battery in a pack with heavy jump start leads is the full 12v and gives 3-500 amps (1300+ Ind) cranking power and is equivalent to jump starting off another car. Battery chargers will charge batteries from nearly flat up to full power given time. Conditioners “mind” batteries over a long period and unless they are high output top of the range jobs don’t charge effectively as chargers (above). Would not be surprised if either a charger or conditioner would give enough output to ping the bonnet latch if fixed to the fuse box post. Someone else may tell me this is all poppy-cock now but that’s my experience over decades of dealing with electrics on cars and Ind machinery. Edited by David W. on Sunday 26th December 14:58

This is what you’re looking for… Image removed now you’re sorted Edited by Paynewright on Sunday 26th December 16:05

I’ve had a few terminal batteries on mine as it isn’t used frequently enough and I have no power in the garage to run a Ctek conditioner (or similar). On the couple of occasions it has been so dead that absolutely nothing works I’ve used a 12v socket to 12v socket charger from my wife’s car. Usually takes less than 60 seconds to energise it enough to use the release. ‘Amusingly’ last time it happened a couple of months ago it wasn’t totally dead so I decided to buy a Ctek CSFree. Actually got the car to start, filled the fuel tank and restarted again followed by a drive until the dash was sitting just above 14v like normal. My years long problem finally solved I though… until two days later when the battery was so dead it couldn’t light up the dash. After buying a new battery I thought I’d see what the CTek could do while plugged into the mains. Eventually it just gave up trying as the battery clearly was properly dead. I think in the future I’ll run an extension cable from the house and give it a day charging the battery once a month during the winter. See if I can make a battery survive more than 2.5 years!

That’s exactly what I’ve done.. it’s on trickle charge!