Hello all, newbie to this site.

I have a 2010 Superb 2.0 diesel Auto Estate

Over the last month or so, my battery was dying for some reason and I replaced it with a decent one. However, this has not resolved the problem. It has been to a VW/Audi garage and they could not find anything mechanically that would cause the problem. I then brought an auto electrician in and he has tried twice to resolve the problem but without success.

According to my multi-meter, the battery goes from 12,4 Volts after driving and then down to 11.4 volts within 24 hours which means I have to boost the battery.

I have tried turning everything off including leaving the car unlocked and alarm off but the same problem happens.

Any ideas?

Cheers

Gary

You have a power consumer which keeps drawing current from the battery, so you need to diagnose it (by measuring the battery current) and pull fuses until you find the circuit that causes the problem.
This should be no rocket science for a decent auto electrician.

Hi, as Andrej suggested to pull the fuses out one by one to locate a faulty module, I would also recommend you this method, This video give you a full understanding on the parasitic current draw chapter

The advantage here is lies in the fact one does not have to pull out fuses ans it will leave the electrical system undisturbed whilst testing.

In the attachment you'll find the related VW technical bulletin concerning this issue.

vw.current.draw.tb_compressed.pdf

Thanks for the advice. I used a supposedly decent auto electrician who came out 3 times (charged £300) and couldn't diagnose the fault.

Have taken the car to a local specialist. Been charged £515 for a full diagnostic check of the electrical system. They say that the drivers seat control unit is faulty and the cost for a fitted new one, coded and labour is £848.99

So that's now going to cost over £1600 for basically a new seat unit. I only paid £2k for the car and have already splashed out on a flywheel/clutch assembly, new wheel bearings (they were really buggered), full service and other smaller things (£2k in total)

Is it worth spending the £848.99 or just scrap the car for parts?

The diagnosis is an easy to do DIY job, watch the video, do exactly the same and you will know for sure where the leak comes from, get the multi-meter and start measuring.
What made the conclude the drivers seat control unit is faulty, what tools did they use, OBDeleven or similar? Did they show you the faultcodes?

I am reading rip-off prices here.