Low Battery Voltage issue

[rafletcher]

So today I went out to set the clock to GMT and so sat in the car, switched on, but didn’t start the engine. Got a 12v Battery Low message on the infotainment. Now, I’ve been having a problem with keyless unlocking not working of a morning, due I assumed to low voltage, so for the past fortnight I’ve been sure to drive around 15 miles each weekday in the (vain, it seems) expectation of charging up the battery to stop this. No go. Checke£ the battery status window and that’s clear so ostensibly ok. Ran a VCDS scan (not that I really understand the output!) in the hope something battery related might show up. I had the engine running and note that the battery voltage start to end of scan was 14v so doesn’t seem to be a charging issue. Of the faults found the vast majority were intermittent so nothing to bother about afaik. Of the confirmed faults one was “Trailer” supply voltage open circuit - I assume the tow bar socket. And e to do with the cameras, missing calibrations but they seem to work ok

I've attached a pdf of the log for those better versed than I in these things!

Whats annoying is the battery is only just over 2 years old!


Secondary question - do I really need to do ant recoding if I fit a new battery?

 

[rafletcher]

Hmm, plugged in the battery charger I remembered getting at the start of lockdown, and it’s telling name the battery is <25% charged! Thankfully the car is still under warranty so Monday it’ll be a call to the local dealer to see what they say - they serviced it a month ago.

 

[Tell]

Either charging or a rubbish battery. I got 5 years out of my factory fitted diesel one but outed it last year since it was showing up on scans and it had a supposed life of 4 years. Did the preventive maintenance one.

Had a previous bad experience with one dying at 11pm at night 12:30am before I got recovery then a 60 mile drive after a day at work with a two hour commute back. Best to take the warning signals seriously.

 

[rafletcher]

Well I’ve charged it back to 100%, will see, with a daily mileage of 15-20, how long it takes to start playing up again. I don’t think anything showed up on the scan that was battery related.

ETA: Well did the 16 mile run this morning. Half way through the stop-start wasn't working. When I pulled up at the end, the engine shut down. Time will tell if things are back on an even keel.

 

[rafletcher]

Aaand... this morning, so 10 days after fully charging it, with 16-20 miles / day except the weekend, kessy once again not working, and the "12 volt battery low..." message on the infotainment screen. I could argue the toss with the local SEAT dealer over warranty, but ICBA, my time is valuable, and anyway I want an AGM battery to replace the EFB+ one that's standard. I could do it myself for £150, but again ICBA and I can fortunately afford it, so it's booked in to a local VAG specialist (VASS Tech in Whitchurch) who'll charge me £286 (£230 + £50 labour) for the priviledge of fitting a genuine VAG AGM battery and of course coding it in, plus maintaining my car settings in the process, which I would inevitable have lost, and all while I wait on Friday afternoon after work. Hopefully this one will last a bit longer than 2 years!

 

[rafletcher]

An update. Even after having the battery changed (slight grumble, they actually fitted another EFB+ rather than an AGM) I found on some mornings that the KESSY didn’t work. Then it kind of penetrated - on a Monday morning, after not having used the car since Friday lunchtime, this would be the case. And no interior lights coming on, no pulsing heartbeat starter button. It seems the car shuts down systems really quite quickly when unused. Oh, and the start-stop has been inactive for a month. Today we went to but the Christmas tree, a distance there and back that I routinely do of a morning. But today it was in daylight, albeit -5C. And guess what - the stop/start worked. So the margins between functional and not are pretty thin.

 

[Tell]

On start / stop it won't function if it decides your battery needs boosting why some people who don't like start / stop drive around with the AC fully on in the newer vehicles that don't allow you to turn it off via coding. Saying that you do hear people moaning about it in dealers where it's not working and think I wouldn't moan . Have my SS coded out and just turn it back on for the service so as not to cause the dealership angst.

On the Kessy you will say it's not that but I do make a point of not burying the key behind things in my bag, so it's always on the outside and isn't screened. I did also notice the dealership had altered the coding so I too get a battery low level for the fod on the dash. Never did, only VCDS / Obdeleven would tell you that. Lucky to get more than 9 months out of the Kessy battery. Runs between 9 - 18 months (on Duracells) and is capable of locking you out when it gives up.