2016 Superb automatic diesel. Started with an intermittent ACC fault and now getting intermittent ABS faults at the same time (which then triggers tyre pressure, park pilot, auto hold, start/stop, etc.).

Diagnostic scan not providing an obvious solution but gave ABS faults on multiple wheels which leads me to think it is not a single ABS sensor issue. Battery is also good.

Also, I don't understand why parking sensors would be affected by this. 

Anyone experience similar issue/solution???

Thanks.

17 minutes ago, Kev8277 said:

I don't understand why parking sensors would be affected by this. 

Parking sensors are turned on/off based on vehicle speed, so if the ABS sensors have a problem the vehicle speed is not reliable and hence the parking sensors report a fault.

 

Multiple ABS sensors reporting an intermittent problem suggests an intermittent connection at a common point, such as the connector on the ABS module possibly due to corrosion, or (worst case) a failing ABS module. Obviously check the connections first!

That now makes sense about the parking sensors.

Good idea on the ABS module connectors, will do that.

All other past experiences/suggestions welcome.

Thanks.

On 05/04/2024 at 09:33, Kev8277 said:

That now makes sense about the parking sensors.

Good idea on the ABS module connectors, will do that.

All other past experiences/suggestions welcome.

Thanks.

Hi did you get to the bottom of this? Facing similar issue but saying rear left

I did.  Both ABS rings on the back wheels looked corroded (using a boriscope) so they were cleaned with some break fluid as good as possible while still on the car.

Changed both rear ABS sensors also and problem solved. Decided to do all this in one garage visit rather than going back and forth to the garage as sensors not that expensive.

Didnt do anything with the fronts as the ABS rings not as accessable.

So cause could have been corrosion on ABS ring, faulty sensor or combination of both. If diagnostic for you is saying rear left then change the sensor but also try look at the ABS ring for corrosion and try clean it as best you can. My diagnostic didnt identify a specific wheel.

I'd also suggested check also, wiring and connections, car battery is in good state of charge and health (as mentioned earlier in thread) and that the scan tool program was for your model and age (VIN?) and is/was fully update before use and that the scan tool battery was in good state of charge (if not powered from car).

 

A few years back a neighbour's Merc had a bad connection to an ABS sensor, away from the sensor (luckily another neighbour's TopDon scan tool could give this detail) being a 2005 Merc dash warnings suggested the world would end if the car wasn't taken straight to a Dealership, the error code cleared and didn't return before the car was taken in a few weeks later to an independent for it's uneconomical tronic gearbox issues sorting and general tarting-up when I guess an arm and and leg was paid out.

 

1 minute ago, nta16 said:

I'd also suggested check also, wiring and connections, car battery is in good state of charge and health (as mentioned earlier in thread) and that the scan tool program was for your model and age (VIN?) and is/was fully update before use and that the scan tool battery was in good state of charge (if not powered from car).

 

A few years back a neighbour's Merc had a bad connection to an ABS sensor, away from the sensor (luckily another neighbour's TopDon scan tool could give this detail) being a 2005 Merc dash warnings suggested the world would end if the car wasn't taken straight to a Dealership, the error code cleared and didn't return before the car was taken in a few weeks later to an independent for it's uneconomical tronic gearbox issues sorting and general tarting-up when I guess an arm and and leg was paid out.

 

The only thing out of the ordinary that I had was a gearbox service earlier that day. Battery terminals firmly connected. Not sure when they put it on the lift if they damaged an ABS wire? But weird to do that. 

Well could be a coincidence or ABS issue was present before the gearbox service was done.  If you are fortunate enough to use a (rare, very, very rare(?)) place that has fair and honourable people owning, running and working at it you could ask if they check just in case.  A friend had her car serviced at a garage and a week later her brother-in-law was driving the car when an oil light came on and it was found then the engine had emptied but as she'd used a good garage they said they'd look at the car and report back, they surmised the sump plug hadn't been torqued up, they sorted all and paid for the AA membership that was used to get the car back so she got a sincere apology and year's worth of AA membership - so the very, very rare do exist.

 

I'd look and/or in the Superb Mk3 forum if doing a gearbox service could be related to cocking something up to end up with a damaged wire for a rear (left) ABS issue or report (assuming rear ABS issue is correct reporting).

 

Good luck let us know how you get on.

 

1 minute ago, nta16 said:

Well could be a coincidence or ABS issue was present before the gearbox service was done.  If you are fortunate enough to use a (rare, very, very rare(?)) place that has fair and honourable people owning, running and working at it you could ask if they check just in case.  A friend had her car serviced at a garage and a week later her brother-in-law was driving the car when an oil light came on and it was found then the engine had emptied but as she'd used a good garage they said they'd look at the car and report back, they surmised the sump plug hadn't been torqued up, they sorted all and paid for the AA membership that was used to get the car back so she got a sincere apology and year's worth of AA membership - so the very, very rare do exist.

 

I'd look and/or in the Superb Mk3 forum if doing a gearbox service could be related to cocking something up to end up with a damaged wire for a rear (left) ABS issue or report (assuming rear ABS issue is correct reporting).

 

Good luck let us know how you get on.

 

Thank you very much. I did take a live reading of all 4 ABS sensors, and the speed reading on the rear left is all over the place. 3mph- then 35 then 4.2 then 18 etc etc 

Probably the sensor and/or ring muck then.  Bear in mind I'm not a mechanic or expert in anything.

 

1 minute ago, nta16 said:

Probably the sensor and/or ring muck then.  Bear in mind I'm not a mechanic or expert in anything.

 

Yeah it's only odd because it's intermittent. It clears itself at time 🤔 so either a cable that's damaged or the ring is mucky/disintegrating.

 

I did take the back wheels off for the breaks  pads job a few weeks ago. But can't see it taking this long to flag up 

I missed that yours was an intermittent fault too, my mistake.  If the rear brakes are like on my wife's 2015 Fabia Mk3 then the pads and discs were the second easiest I've ever replaced (not that I've done many), easiest were the Fabia's front discs and pads but I'd guess the Superb has more complications around the wheels.  As before it could just be a coincidence or was present before you done the work, or you might have caught something perhaps.

 

Another coincidence ,is I've just finished watching the following video (I'm a Subscriber), check out the first car, I like this chap as he checks and double checks stuff and doesn't mind saying or putting when he's made a mistake, might give you an idea of somethings to check.  I also like he uses good basic things like a headlight bulb for load testing where appropriate and wiggles wires and connections (hot, cold, wet, damp, etc. can also make differences especially to intermittent).  HTH a bit. -

 

 

On 12/01/2025 at 18:24, nta16 said:

I missed that yours was an intermittent fault too, my mistake.  If the rear brakes are like on my wife's 2015 Fabia Mk3 then the pads and discs were the second easiest I've ever replaced (not that I've done many), easiest were the Fabia's front discs and pads but I'd guess the Superb has more complications around the wheels.  As before it could just be a coincidence or was present before you done the work, or you might have caught something perhaps.

 

Another coincidence ,is I've just finished watching the following video (I'm a Subscriber), check out the first car, I like this chap as he checks and double checks stuff and doesn't mind saying or putting when he's made a mistake, might give you an idea of somethings to check.  I also like he uses good basic things like a headlight bulb for load testing where appropriate and wiggles wires and connections (hot, cold, wet, damp, etc. can also make differences especially to intermittent).  HTH a bit. -

 

 

So Abs sensor replaced (£30 bosch one not £115 Skoda mark up one). 2 days now no faults. Usually came up within 15/30 mins of driving 

if you got 2 days, then good chance its sorted....at a nice price too.