Intermittent horn/ACC failure

[steevs]

Hi all,

 

2020 Superb SportLine Plus

 

I've recently been experiencing an issue where in the morning, specifically on colder days - my horn and ACC will stop working.

 

I've checked error codes and it is simply showing "databus error received"

 

There is no meaningful errors being stored.

 

Oddly enough, if I restart the car, the issue disappears until the following day.

 

Funnily enough, it only started occuring a month after my warranty expired...

 

I've looked for any parts revisions on the steering column module and clock spring and apparently my specific part number (5Q1953521AG) has two revisions but unsure on coding.

 

Any thoughts on this would be great, thanks!

Edited 16 January by steevs

[ApertureS]

You’ll need to supply the complete fault code please.

 

I assume you’re using vcds/obd11? In which case the full fault code won’t contain everything, if scanned with odis it will tell you exactly what module is sending a fault and what message it’s trying to send.

 

I also assume based on your other posts that you’ve made some software changes to your car? If so, have you tried reverting them as it will have been something you’ve done probably 

[steevs]

6 hours ago, ApertureS said:

You’ll need to supply the complete fault code please.

 

I assume you’re using vcds/obd11? In which case the full fault code won’t contain everything, if scanned with odis it will tell you exactly what module is sending a fault and what message it’s trying to send.

 

I also assume based on your other posts that you’ve made some software changes to your car? If so, have you tried reverting them as it will have been something you’ve done probably 

 

I'll need to try find somewhere that will give an Odis printout, as for obdeleven tweaks; I reverted fully back to standard coding and adaptions but the problem still persists.

 

It seems to be voltage related, I noticed there's another discussion about this exact issue going on over on Reddit.

 

I am also rarely getting start/stop to happen and have seen a few function restriction due to low voltage codes being stored.

 

Battery is less than 2 years old and alternator has been tested and working well but it drops to under 12v overnight.

Edited 16 January by steevs

[Crasher]

We see this a lot and the radar sensor with internal water damage. What is the VIN?

[SomersetSkodaSuperb]

Oddly enough I found the same issue with the horn the other day when the temperature was below freezing. Shortly afterwards it was all working again. I know the ACC can be fickle with cold weather, it’s often mentioned on the forums but the horn was a new one to me. Be interested to see if others find they have this ‘quirk’.

[steevs]

Following this up with a bit more info, today got a P056800 on the engine module.

 

Additionally when checking the ACC operating lever signal, it is stuck at 1011000 until restart.

 

Will try find someone nearby at the weekend for a proper Odis scan.

[Crasher]

Yes yours has the early radar sensor we have seen problems wit water getting inside.

[StoneFist85]

On 16/01/2024 at 13:08, steevs said:

 

I'll need to try find somewhere that will give an Odis printout, as for obdeleven tweaks; I reverted fully back to standard coding and adaptions but the problem still persists.

 

It seems to be voltage related, I noticed there's another discussion about this exact issue going on over on Reddit.

 

I am also rarely getting start/stop to happen and have seen a few function restriction due to low voltage codes being stored.

 

Battery is less than 2 years old and alternator has been tested and working well but it drops to under 12v overnight.

I had exactly the same problems in my 2020 SEL Exec. Only got car few weeks ago. Start stop hardly ever worked, even after 120+ miles drive, was showing vehicle high power consumption, then ACC and horn got temperamental. Got it back to dealer, they've replaced battery and so far all ok. Said they'll order clockspring and lever for ACC as there were some errors but haven't heard back from them yet.  (It's indy dealer, not skoda)

[steevs]

9 minutes ago, StoneFist85 said:

I had exactly the same problems in my 2020 SEL Exec. Only got car few weeks ago. Start stop hardly ever worked, even after 120+ miles drive, was showing vehicle high power consumption, then ACC and horn got temperamental. Got it back to dealer, they've replaced battery and so far all ok. Said they'll order clockspring and lever for ACC as there were some errors but haven't heard back from them yet.  (It's indy dealer, not skoda)

 

Interesting, my battery is less than 2 years old AGM Varta 70ah.

 

I've tested (and had tested for my own sanity) and shows 2/3rd of it's original cranking capacity but still charges correctly.

 

I have measured it dropping to less than 10v during cranking but the car modules show a voltage of 11v when the steering switch module logs an error.

 

Keep me posted on if this stays resolved, a bit dangerous the fact that the horn fails if battery voltage drops though.

[StoneFist85]

Well my cars battery was barely 3 years old (67k miles) and also 70ah varta AGM. Got that. 

1 hour ago, steevs said:

 

Interesting, my battery is less than 2 years old AGM Varta 70ah.

 

I've tested (and had tested for my own sanity) and shows 2/3rd of it's original cranking capacity but still charges correctly.

 

I have measured it dropping to less than 10v during cranking but the car modules show a voltage of 11v when the steering switch module logs an error.

 

Keep me posted on if this stays resolved, a bit dangerous the fact that the horn fails if battery voltage drops though.

2/3rd of capacity I would say is bad for start/stop battery. I had 8 year old varta on my 2015 octavia and it was still working OKish. Car was starting and all but started having some issues and errors on dash. Only thing was- I've disabled start/stop shortly after buying car (4 years and 75k miles when bought). Sold it with 145k miles.

 

So I would start with replacing battery. Now in superb I have to remember to switch off start/stop every time I start car as it is working again and from what I found it can't be switched off using obd11