is this the ground nut that a couple of people have referred to? The cable (or sheath anyway) is black though, not brown.

My socket set didn't go large enough to undo it and clean it (another purchase - just ordered the xzn's which were the equiv of $28 USD - we get ripped off in the EU for some things...)

But it was certainly finger-tight. I'll get a socket and undo it and clean it though - presuming this is the right one?

Thanks

 

Yes, taking that off will kill power to everything.

 

Thanks. My father-in-law is lending me a larger socket set this afternoon so I can take it off and clean it.

 

Have you checked the actual battery that is under the driver's seat? Like have you actually put your eyes on it?

 

I haven't got the xzn triple square bit to take the seat up. It's on order and I'll get it Friday. But the battery is only a few months old. Put in my a mechanic I trust and one that is up to spec. I've gone through several batteries in the last few years including the official 'Porsche' one (rebranded Bosch?) fitted by Porsche.

Why do you ask?

I will check it when I get the bit, but each time the battery has been replaced - by mechanics, including Porsche, who knew of the electrical faults no one ever said 'oh the battery was leaking/damaged/etc'

 

Getting a meter directly on the battery terminals will narrow your problem down between a high resistance connection or a parasitic draw. You'll instantly eliminate 50% of the current guesswork. There is a lot under that seat between the battery and the rest of the car.

Did you check any local auto parts stores for the triple square bits? Most in the US have them on the shelf for about $10 a set.

 

Understood, thanks.

I'm in Malaga, southern Spain. Not that many and not local. I am driving towards the airport later to pick someone up so I'll try to find a shop if I can and cancel Amazon (hasn't shipped yet and won't be here until Friday). But it's harder to get most things over here.

 

 

Not sure there is an outcome yet but since I cleaned the ground cable/bolt, it's started every day. BUT it can go through phases of doing that - normally after I've done something to 'fix' it, and then i think it's fixed and eventually it goes again.

I've now got the tool to get the seat up. I've not started the car now for about 30 hours (I did open the door about 5 hours ago to get my driving sunglasses so I could use my wife's car so that will have woken it up).

I'm going to go down to the car now and get to the battery and test the voltage directly on it and compare it to the reading on the posts.

I'll also do a visual check on it etc. Then - depending on the voltage reading of course - I'll try to start it.

If it's still dropping or doesn't start, I'll get going with the suggestions above, now I can get to the battery.

If it isn't dropping and works, well... I won't get too excited about that yet! I'll report back. Thanks.

 

Well, bit of an update.

Let's call it a work-in-progress (BIG LOL)

First thing - the reading was 9.00v on both the terminals and the battery, so it's still dropping and that rules somethings out.

I've just spent 3 hours ripping out every last piece of aftermarket wiring, cd players behind the seats, screens in the headrests, and more (crappy) cable than I can describe. Most of it was really badly made and wired up, and some of it was in pieces having disintegrated.

But... I don't think any of it was actually connected to anything as we (the mechanics and myself) took all connections to the car out, or at least I thought we had. Anyway, for sure now it's all ripped out.

Although I had the battery ground disconnected throughout, I had to reconnect and put the jump starter on (but not starting the car) to move the seats back and forth etc so by the end the battery was down to 7.90v.

Before calling it a night, I jump started it to check the car still worked and it did. Voltage when running was 14.something.

Then I turned it off and took the key out.

I checked the battery again and it was at 9.something v but was dropping 0.01 every 3 seconds. The key was out, but of course the lights and computers etc were still running as I'd just turned it off. Maybe that's normal?

But now, I have the car in pieces. Drivers seat up, passenger seat out, lots of the interior out, the cd changer out etc etc. But I had to stop at 9pm, I was shattered.

Tomorrow I'll put it all back together and after a charge see if anything has changed or not. But if not, at least I know all the crap is out.

 

The battery at this point may be permanently damaged. AGM/Lead-Acid batteries aren't happy when they've been basically totally discharged. 7.9V is bad.


If this happens the battery is damaged and may never be able to fully charge again. This might be the case here. The test would be a "load-test" - which most any big-box auto parts store will do for free - if you bring the battery in (out of the car.) It sounds as if your charging system is doing what it's supposed to - with that badly discharged a battery, I'd expect full output from the alternator - which will be somewhere around 14.6-14.7V. It sounds like it's doing that.

If the battery fails the load-test - then after you get your new battery - before installing it - charge it overnight so you're certain it's fully charged (despite what the stores claim - new batteries don't come fully charged.. and the manufacturer usually recommends full charge before installation.)

Install it - then click over the latches for any door that is open, have the hood up already, and do the voltage tests we suggested after the computers go to sleep.

It is possible at this point that you've fixed the problem of parasitic current draw when the car is off and it's simply the battery has been so damaged by it's former discharges that it can no longer hold a charge.

Good luck!

 

Yes, I know - the problem is I have bought so many batteries over the last 2 years or so on the same basis. I can't keep buying batteries only to write them off in a couple of months.

This is the current battery btw - https://www.yuasa.co.uk/ybx5020.html

It has a state of charge indicator - I'm not sure exactly how it should look, but it seemed to be green (although it wasn't a green background with a white tick as the label suggests). It certainly wasn't white or white with a red x which is 'replace battery'. But I'll get a load test done. Thanks.

 

Perhaps it's still under warranty?

 

I only got it a few months ago so yes, but would it be covered for something like this? It's not a fault of the battery, it's a fault with the car that has damaged the battery?

 

How would they know this? Unless they ask, you're under no obligation to tell them this has been suggested as a theory (and not proven so far..)