996 storage / battery care - Page 1 - 911/Carrera GT - PistonHeads UK

I have a 2001 MY 996 with the electric bonnet release. I was reading the manual to understand how best to store the car and a few things aren’t very clear. Car has the electronic bonnet release and is parked in an underground car park with no power for a trickle charger. What is the best way to leave the car if it won’t be driven for several weeks at a time in order to minimise battery decay and ensure I can get back in when needed? - should I disconnect and / or remove the battery? Does this present any fault codes or do any damage to the car / battery? - if I remove the battery and close the bonnet, how do I open it to put the battery back in? - if I am going to leave the car to minimise battery drain, can I leave it unlocked and unarmed? Or is there a better way? Garage is secure so I am less concerned about theft. I’m a bit confused with the permutations and would appreciate any advice from those who have done this before. Thanks

Hi, I have a 2003 996 with the same electronic bonnet release. I’m fortunate enough to be able to connect to a battery conditioner when parked, but have looked into this topic a lot in the 9 years I’ve owned the car. Basically it’s a bloody nightmare if your battery goes completely flat! The reason is as follows: If the battery goes flat you cannot open the bonnet the normal way. There is talk of potentially jumping power to the fuse box to enable the electronic bonnet release, but people who have tried seem to find this difficult. So you have to use the manual bonnet release. Jack the front right (I think) up, take the wheel off, remove the arch lining, then pull the manual bonnet release cable. Easy right? But wait….to get the wheel off….you need the locking wheel key….which is generally stored in the toolbelt….UNDER THE BONNET!!! First step is to buy a really good quality new battery that you religiously replace before its guarantee expires. I use this one: Bosch S5008 - car battery - 77A/h - 780A - lead-acid technology - for vehicles without Start/Stop system - Type 096 Next make sure you can use the manual release system if you need to. As a minimum, keep the locking wheel key in the glovebox rather than under the bonnet. Alternatively, a few people have rerouted the manual release cable from behind the wheel arch to the front bumper and zip tied it to the tow hole cover (not tried this myself so can’t comment on how fiddly this is). You would need some kind of battery booster pack once you get access to a flat battery, I can’t advise you on which to get unfortunately as I’ve never had to use one. If your battery does go flat though I would replace it immediately as it will be forever weakened and not hold charge as effectively. Replacement batteries are pretty affordable, I last bought one a couple of years ago from Amazon for approx £100. I’ve been warned that the alarm system will drain a battery flat after 2 weeks. No idea if this is true or not, would probably be longer for a young high quality battery, but if you think you will frequently not drive the car for a month or more, then you could disconnect the battery (to reduce drain to near zero) and resign yourself to using the manual bonnet opening method every time. I would not recommend leaving the bonnet open/unlatched to avoid the hassle - you’d only need to forget to close it once before driving off and it could wrap itself around the windscreen once you’re up to speed. I’ve been a co-driver in a rally car when that happened and it’s quite unpleasant!

Same situation. If the car isn't driven for a while, I have a battery breaker which I disconnect and then lock the car with a key with front bonnet left open. Eventually I'll open up the release mech and cut off the little pin which locks the lever in place. Mine has the cable release but same thing happens. The good thing about the electric one is that you can open the fuse box and power it from there. Very easy, check YouTube

Buy a portable jump pack and a cigarette lighter extension. Cut the female socket off and then attach the jump pack to it and plug it into the lighter. This will allow you to open the bonnet, easier than attaching to the fuse box, and then put the jump pack on the battery to start the car.

Thanks all for the feedback, what a daft set up! I think I’ll be getting a jump pack and starting it up that way. I’m sure it is straightforward once I’ve done it a couple of times but seems ridiculous. Surprised someone hasn’t come up with a nice easy fix!

I've read it is possible to relocate / extend the manual bonnet release to it is to the rear of the front grill. It is on my list to do as last year the electrical release failed on a very hot day and it was a pain to get to it - never had an issue with it since mind. The best option maybe to leave it 'on the latch' and pop a car cover over it

If I leave the bonnet on the latch, the boot compartment light seems to stay on which I presume will run the battery down? Anyone know where the switch that triggers the light is? Could just take the bulb out I guess.