Hello fellow Skoda owners!

Mother has a Fabia 1,0t (110hp) with dsg. When she was out driving last week the display started blinking like a video game. I conncted my Obd11-scanner and find 20 fault codes. My exeprience from 8 years with a Golf Alltrack is that when this suddenly happens it's time for a new starter battery.

Checked the battery voltage and it was like 11,9v. So she bought a new battery, I coded the new battery to the car and the car worked fine, for a day. Then the display lighted up like a video game again with 20 different fault codes. So I think there is some electrical issue. Can any one point me in some direction where to start searching for faults?

Hi, welcome.

You don't say what year your mum's car is, that could be important.

For low battery often they can be recharged with an appropriate battery charger (even VAGs) 😄 but I can understand with relatives and friends often it's easier to replace the battery.

Could be electric wire(s), connections, relay(s) or board or other stuff.

Did you clear the error codes with your OBDEleven after the new battery was fitted or check for them after the new battery was fitted?

Was your phone battery with reasonable charge, OBDEleven program fully up to date, good wireless connections with no drop outs when you 'coded' the new battery (and check for error codes)?

Was it just short journey(s) your mum did for a day?

First check the battery and its installation, then check your coding of the new battery, mistakes can happen.

What were the 20+ error codes?

Sorry for all the questions but only you were there and have the car and tools in the metal and plastic and not anyone here on site so it's starter diagnostics, some might give quick answers or suggestions but obviously that not me (other than as I've already put).

The Fabia is 2019 model.

I've tried first to charge the old battery with one of my Cteks, but the voltage wouldn't go higher than 12,2v. Tested the battery with my batterytester and it said 33% life remaining. There for she bought a new battery. Her dayli driving is like 3km to the grossery store and the car runs like 3000km a year. Not ideal for the battery, that's why my conlcusion was that it neded a new battery after 6 years.

I've reset the fault codes 2 times after coding the new battery, and I think my gear is up to date. Used my obd11 last month for realeasing handbrake on wifes Golf, so it should be fine. The new battery was charged to 100% before she took the car for a drive, but the codes still coming up.

Tested the voltage while enginge was at idle and the generator didnt charge. Mum repedatly floored the gas pedal and rev the engine to 4000rpm and after a couple of times it showed +14v. Not shure how the BMS works on VW but I belive the generator only charges when BMS demands it?

The fault codes after replacing the battery was:

Engine electronics 2 faults

Gear electronics 1 fault

Break eletronics 4 faults

Climate conyrol 1 fault

ACC (adaptive cruise control) 7 faults

CAN 3 faults

Steering Wheel lockup 2 faults

Power steering 1 fault

Parking sensors 2 faults

Keyless 2 faults

I've read som issues with the fuseholder/relay (vw 6c0941824d) in the fusebox on some Fabias that can give multiple fault codes for no reason. It's like the computers in the car go fanatic when there is a low voltage/bad ground issue, like a bad starter battery or some bad connections i the fusebox.

10 minutes ago, Tompamannen said:

It's like the computers in the car go fanatic when there is a low voltage/bad ground issue, like a bad starter battery or some bad connections i the fusebox.

And that is the whole of the Zeroth Law of VAG electronics.

Have you checked the alternator control wires yet? Likely diagnostic here is if you switch the ignition on and the battery light does not come on.

Obviously diagnostics isn't jumping to conclusions but as you've obviously read up on such stuff that dodge poor quality fuse holder relay (too cheap quality IIRC) might be a suspect (more proof (VAG) German engineering quality isn't necessarily high (German marques quality fell before and just after the turn of the century.

The battery voltage doesn't have to be that low for all sorts of unexpected warning lights, messages, issuers and error codes.

One computer system issue can bounce around the others and cause them to join in, a good reason to clear all error codes when possible (and not let your battery state of charge get too low for the like of the computers, preventative charging is useful in a situation like your mum's before the battery is used, abused and neglected too much to often).

Good to recharge the battery to 100% (rather than the VW stop/start battery management of ?70/75/80%?) so I'm not surprised the charging numbers remained low, more surprised you can rev to 4,000 rpm with the car stationary, I don't think there's probably any alternator issue from what is in your posts - but main things like faulty ignition switch could also perhaps create and error code list. There is a thread on here with (IIRC?) posts from a chap that done his own repair to the relay, if you find that you could see if the relay symptoms and diagnosis fully relate to the problem with your mum's car.

DSG may introduce another level of PITA, sorry, complexity, and possibilities of faults but OBDEleven only give it one count so it may be an innocent party here.

Do check your OBDEleven is up to date for your mum's car or generally, if you are doing diagnostics you check rather than assume, I have no idea what is required on an OBDEleven other than your wife's Golf isn't a 2019 Fabia, differences, changes and updates can relate to VIN/car built level. It is another subject we can cover later if you want but as you know not to fully trust the computers also do not put all your faith into your Cteks and your battery tester.

The CAN three faults might be something to expand on further.

If you know anyone with another 2019 Fabia appropriate scan tool you could confirm OBDEleven results and perhaps get more info and diagnosis.

Are you your mum's car) in Ireland or somewhere (else) in Europe, in case things vary as most members here work from a UK perspective of the cars?

ETA: sorry I've just found the relay issue related to cold starting issue (vw 6c0941824d) so may not relate to your mum's car.

Also if you mean the dash display was blinking on/off then that is a different issue anyway.

Do any of these error codes effect your mum's car driving?

Hello, thanks for all your inputs!

Will check the alternator battery warning light, had completely crossed my mind.

The car works perfectly. I will look into the electrical scheme. I think the issue is some kind of communication error between the VDCM and the modules of what I can tell from the OBD-logs.

Don't put all your eggs in the OBDEleven basket, all information from all sources needs checks and cross referencing, included car and other manufacturer's, strangers on the internet, and scan tools. You can check items with your senses and other diagnostic tools like a multimeter.

Never forget or overlook the basics, a bent or furred up pin on a plug, connectors, wires, can cause issues with transfer of power or communication. You could look at for water ingress for any reason too perhaps near these items.

You may need a wiring diagram and information on location of modules, I believe you can pay €7 (?) and get an hour to download as much information as you can find, I have never done it so don't know the details and other similar services are available but might be subscription.

Good luck, let us know how you get in to help other later.