My partner has a 2018 Fabia 1.0 TSI Break with around 55k km on the odo, and claims to have had 2 braking glitches over the past few months. The first caused her to warp the parking gate at work, the 2nd was today where apparently it took her some 40m to stop from doing 40 km/h, with the ABS engaging.

There may have been frost on the road, but almost certainly no black ice, and she drives on low-mileage winter tyres.

 

I wasn't there so I can't put things into context, but there were apparently no warning lights.

 

Are there known issues that we should be concerned about, like ABS sensors that signal false positives without testing faulty?

What was the weather like at the time of the first incident?

 

There might well have been ice on the road, it doesn't matter what tyres you have on, on ice they will lose grip if the limits of traction are broken. Even frost might have been enough to have the same effect if the road surface was very smooth.

 

However you might be worthwhile getting a diagnostics plug in and check the ABS system for faults, it's highly unlikely that there would be a fault and it not show up as a light on the dash.

 

I trust the brakes are well serviced, fluid changed etc?

Edited 11 December, 20214 yr by HeavyMetalRich
Added info

floor mat  getting in the way ?

We've got rubber floormats in our car, so little chance they get in the way

 

Usually a bit of frost doesn't pose a problem esp. with winter tyres, but today's event could certainly have involved a dose of fallen leaves too. The 1st time must have been in May or June, so no ice possible.

 

If there are no known issues that could be at play here we'll just continue to use the car (fortunately 90% of the trips taken in that one are on largely empty country roads), and trust that  the implicated systems are all designed in such a way that any errors are communicated to the driver. IOW, anything that would show up now in the VSDC would give rise to a warning light and/or message on the status screen?

Tell her if the ABS engages in snow or ice  conditions and it does not seem the car is slowing down or rapidly enough (seems to be surging between applications) she must declutch straight away.

 

It's counter-intuitive for someone who has been driving a long time without ABS.

 

Something else to learn for any emergency stop to avoid an obstacle is to steer around it while hard on the brakes and declutched, once again very very counter-intuitive but the real value of an ABS system is the ability to have maximum braking effort and be able to steer around or evade an obstacle. This skill is best practiced in an empty snowy car park.

49 minutes ago, RJVB said:

today's event could certainly have involved a dose of fallen leaves

Yes; wet fallen leaves are about as slippery as ice.

Thanks, I also didn't know about declutching. I've only know vehicles with ABS, but this wasn't taught...

(sadly the 1.0. has about 0 engine break, so you learn to use the brakes for everything...)

Techniques like that are well beyond the teaching for the driving test.

 

It was more a case of unlearning something that you may have been taught or may have found out yourself through experimentation or the hard way through accident, with a standard braking system swerving whilst doing a full on emergency stop would usually result in a total loss of control and a spin, experienced drivers would cadence brake which would allow some limited steering response but still likely to spin, basically you would anchor up, maintain the same trajectory and if it was clear you were not going to be able to stop before hitting the object/vehicle let off the brakes and swerve (probably spin) at the very last instance.

 

Someone who has only ever known ABS will probably have adapted to steering while emergency braking or at the least wont have been told not to do both. The  surging forward on ice during an ABS stop if not declutched is unnerving the first time it happens and only really a problem with powerfull engines as they pour on the coals to prevent the engine stalling. My XR4x4 Sierra would plow on for ever with my foot pressed as hard as I could on the brake on snow or ice, declutch and it stopped immediately.

 

It's very hard to unlearn automatic responses, it takes practice and that what I did lots of in 1987 with my first ABS equipped vehicle, in later years I had my road (ABS) responses and my racetrack (no ABS, no stability systems) responses.

This reminds me of a study about ABS benefits I read long ago. I can't remember the details, but IIRC there was a difference between a) drivers accustomed to non-ABS braking; b) drivers not having that experience but no ABS-specific knowledge (i.e. taught "just brake as hard as it takes") and c) drivers who'd learned to exploit ABS. The latter were the safest drivers, the first the least.

 

But just to be certain, when you say "de-clutch", you actually mean *engage* the clutch (pedal) so that the engine can't stall? Initially I'd thought that you meant to release the pedal in order to benefit from the extra engine braking power... That's what I do, but keep my foot ready on the clutch to engage it as soon as I hear the engine is no longer being driven. I haven't yet had much emergency testing, though (knock on wood).