Hi all, 

Just drove to work this morning in some rain. Noticed going through the lanes that any sort of braking would result in excessive ABS even at low speeds. I had to brake harshly at 20-25mph as someone bombed around the corner, and all my car did was excessively engage ABS to the point as if it felt the car was not going to come to a stop. It felt as if I had next to no brakes. So outside work I hit the brakes harsh at say 15 to 20 mph, if that, and again excessive ABS feedback. Could this possibly be a one off or does it warrant further investigating? I'm in work for the next 24hrs so won't get the chance to give the car another drive and do further investigating until tomorrow. 

Could well be one of the wheel speed sensors giving duff info to the control module.

Not sure of exactly the best strategy for diagnosing this.  If you have VCDS or know someone that does you could maybe look at the outputs of each sensor and see if one stands out as 'odd'?

 

 

1 minute ago, Breezy_Pete said:

Could well be one of the wheel speed sensors giving duff info to the control module.

Not sure of exactly the best strategy for diagnosing this.  If you have VCDS or know someone that does you could maybe look at the outputs of each sensor and see if one stands out as 'odd'?

 

 

Thanks buddy, I'll try and get it checked out. Just a shame I'm in work today. Fingers crossed it'll pose no issue when I jump back in the car tomorrow, but it's besides the point ain't it. 

You could temporarily disable the ABS system by removing a fuse or two, which would restore conventional braking, but I don't know which fuses as I don't have mk3 info.

 

Are you declutching when you do these emergency stops?

 

I know its contra-intuitive but you must learn to do this during an emergency braking manouvre to allow the ABS to work effectively on all wheels, you also have to learn to steer during the manouvre, again counter intuitive but the ability to do that while emergency braking is the raison d'être of ABS.

 

Its not apparent at higher speeds but at low speeds if you dont declutch the anti-stall feature of the ECM will be fighting against the brakes, a graphic example of this were my Sierra XR4x4's of the late 90's, playing in a snowy car park an emergency stop when declutched would have a longer stopping distance than on dry tarmac and with loads of ABS oscillation, doing the same without declutching resulted in the 3 litre V6 engine surging and the car just pushing on against much reduced ABS intervention ad infinitum, it would never come to a stop until declutched.

43 minutes ago, J.R. said:

Are you declutching when you do these emergency stops?

 

I know its contra-intuitive but you must learn to do this during an emergency braking manouvre to allow the ABS to work effectively on all wheels, you also have to learn to steer during the manouvre, again counter intuitive but the ability to do that while emergency braking is the raison d'être of ABS.

 

Its not apparent at higher speeds but at low speeds if you dont declutch the anti-stall feature of the ECM will be fighting against the brakes, a graphic example of this were my Sierra XR4x4's of the late 90's, playing in a snowy car park an emergency stop when declutched would have a longer stopping distance than on dry tarmac and with loads of ABS oscillation, doing the same without declutching resulted in the 3 litre V6 engine surging and the car just pushing on against much reduced ABS intervention ad infinitum, it would never come to a stop until declutched.

Best way I can describe is that the abs is excessive. For example, I drove at 15mph, got my speed down to 5mph and then slammed the brakes. Once I slammed the brakes at 5mph the abs still kicked in. Surely this isn't right? I don't see how or why it'd kick in at such slow speeds. Or even why such a feature would be relevant at 5mph?

 

Also in answer to your question, I do not recall. However were I to slam the brakes I suppose my instinct would be to press the clutch down to prevent stalling. 

 

My car is a 2015 and has done 37 thousand miles. 

 

Edited 29 June, 20223 yr by CReese123

What state are your tyres in?

 

Maybe they have very little grip causing them to lock sooner than you'd expect and ABS to kick in 

What tyres,

what pressures,

and has the 7 year old car had the brake fluid changed at 3 years, 5 years or anytime or tested for H20,

What servicing have the brakes had, pad change or anything? 

12 minutes ago, roottoot said:

What tyres,

what pressures,

and has the 7 year old car had the brake fluid changed at 3 years, 5 years or anytime or tested for H20,

What servicing have the brakes had, pad change or anything? 

 

19 minutes ago, langers2k said:

What state are your tyres in?

 

Maybe they have very little grip causing them to lock sooner than you'd expect and ABS to kick in 

 

Back tyres have 4mm of even tread. Front tyres are brand new midrange tyres (less than two weeks old). 

 

Front and rear brake discs and pads were changed all round at the start of the year, along with a complete fluid flush. 

 

Tyre pressures are checked regularly and set at the manufacturer recommended PSI of 30 (checked them this morning before leaving for work, oddly enough). 

Edited 29 June, 20223 yr by CReese123

There you go.  Maybe the issue.   What are the new tyres?

Green tyres, not run in.     

?

How many miles since in that 2 weeks?

 

OK, tyres set cold is good, 

what size are they?

 

At least not set at a Ditch Finder ECO pressure or left as a Tyre Fitter might have had them at.

Edited 29 June, 20223 yr by roottoot

1 minute ago, roottoot said:

There you go.  Maybe the issue.   What are the new tyres?

Green tyres, not run in.     

 

OK, tyres set cold is good,  what size are they?

I'm unsure buddy, given I've only noticed this today after two weeks. I'd have thought if it were tyre related I would've noticed the issue instantly upon changing them? I've drove a decent amount in the meantime. 

 

Sumitomo tyres - 185/60r15

 

Surely abs engagement at 5-10mph isn't nt meant to be, though, regardless? 

Simples then.

Later go find a safe place, an empty car park, trading estate or road and try out your braking and ABS.

 

Be sure today was not the road surface, spills or the likes and it is the car that is the issue, or maybe the tyres / pressures. 

 

So not considered ditch finders, just reasonably cheap tyres that are hard wearing and not so good at stopping maybe. 

Edited 29 June, 20223 yr by roottoot

17 minutes ago, CReese123 said:

I'm unsure buddy, given I've only noticed this today after two weeks. I'd have thought if it were tyre related I would've noticed the issue instantly upon changing them? I've drove a decent amount in the meantime. 

 

Sumitomo tyres - 185/60r15

 

Surely abs engagement at 5-10mph isn't nt meant to be, though, regardless? 

If there's a fault in the ABS system so that ABS kicks in when there is no loss of wheel traction, then presumably there would be little to no difference in the behaviour of the ABS system regardless of whether it was wet or dry. So if the issue happens just as much in the dry as in the wet, then it would indicate a fault in the system.

If you can only get it to happen in the wet, then it sounds like the tyres are not gripping the road correctly.

 

 

1 hour ago, roottoot said:

Simples then.

Later go find a safe place, an empty car park, trading estate or road and try out your braking and ABS.

 

Be sure today was not the road surface, spills or the likes and it is the car that is the issue, or maybe the tyres / pressures. 

 

So not considered ditch finders, just reasonably cheap tyres that are hard wearing and not so good at stopping maybe. 

 

 

45 minutes ago, EnterName said:

If there's a fault in the ABS system so that ABS kicks in when there is no loss of wheel traction, then presumably there would be little to no difference in the behaviour of the ABS system regardless of whether it was wet or dry. So if the issue happens just as much in the dry as in the wet, then it would indicate a fault in the system.

If you can only get it to happen in the wet, then it sounds like the tyres are not gripping the road correctly.

 

 

 

What would both of your opinions be on ABS kicking in at extremely low speeds?  That's what stands out to me the most. I also quickly tested the brakes again in the car park 10 minutes ago without going crazy. And as before, at 5-10mph the ABS is kicking in if I slam harshly on the brakes despite little to no speed and the road surface now being bone dry. 

 

I'll drop my car off at the garage tomorrow and see what they say. I'll update you guys. 

Edited 29 June, 20223 yr by CReese123

18 minutes ago, CReese123 said:

What would both of your opinions be on ABS kicking in at extremely low speeds?  That's what stands out to me the most. I also quickly tested the brakes again in the car park 10 minutes ago without going crazy. And as before, at 5-10mph the ABS is kicking in if I slam harshly on the brakes despite little to no speed and the road surface now being bone dry. 

 

I'll drop my car off at the garage tomorrow and see what they say. I'll update you guys. 

I think @Breezy_Pete has the solution here: disable the ABS completely and see what happens when you jam on the brakes at low speed.

If the wheels lock, then there's your answer.

I think this is what you want. https://manuall.co.uk/skoda-fabia-2016/

(Image below is a grab from page 166 with highlighting and arrows)

There are plenty of suggestions online that older systems only worked at high speeds.

 

I can't see any confirmation regarding the speed ABS works down to on modern VAG vehicles.

 

I'd expect it to work down to almost zero given it'll have various accelerometers, yaw, roll sensors etc and know when the vehicle is actually at a standstill. Thinks have moved on quite a bit since the earlier ABS systems

The All New 3rd Generation as Skoda called the Mk3 Fabia launched in 2014 did not require new Type Approval which meant they were after 2011  but still did not need DRL's as standard from the factory.

 

VW / Skoda changed the platform, track, wheel base, tornado lines,  a bit of a change from the MK2 but nothing much other than some tweaks and changes and Euro 6 engines. 

 

Skoda were offering ESP as an extra  cost option on some Mk2 Fabia years after other manufacturers had it as standard even on cheaper cars and only had it on all models when EU legislation meant they had to have it. 

 

Re-engineered.    Vorsprung Durch Technik. Turn it out cheap and be sure not better than a Polo a A1 or even an Ibiza.

http://autoevolution.com/news/all-new-2014-skoda-fabia-first-photos-of-third-generation-model-81536.html

 

Edited 29 June, 20223 yr by roottoot

Reading the VW Self study program for the system, there is a pedal pressure sensor and it bases part of the ABS regulation on this info coupled with the wheel speed sensors, so if it thinks you have "stamped" on the pedal it will bring in the ABS function, I wonder if your pedal pressure sensor is giving the impression that you are stamping on the pedal and so kicking in the system ? a live data readout from VCDS might be able to confirm this 

42 minutes ago, nige8021 said:

Reading the VW Self study program for the system, there is a pedal pressure sensor and it bases part of the ABS regulation on this info coupled with the wheel speed sensors, so if it thinks you have "stamped" on the pedal it will bring in the ABS function, I wonder if your pedal pressure sensor is giving the impression that you are stamping on the pedal and so kicking in the system ? a live data readout from VCDS might be able to confirm this 

Hi buddy, that's interesting to hear. Where did you read this? Would pushing the pedal to its limit class as stamping? If so I've been doing this when investigating why it's engaging the abs at stupidly low speeds; pushing the brake pedal to the floor (sort of speak). I thought abs is speed regulated, though, and only engages when the wheels lock? I didn't think pedal input was relevant beyond it's potential locking of the wheels with brake force.  I also don't see how it would register below 10mph as brake locking should be irrelevant and next to nothing at such low speeds. 

Edited 29 June, 20223 yr by CReese123

1 hour ago, nige8021 said:

I wonder if your pedal pressure sensor is giving the impression that you are stamping on the pedal

He is stamping on the pedal, he is doing a full blown emergency stop at 5mph (probably more) a speed where the wheels will easily lock up trying to stop the momentum of over a tonne of vehicle and then complaining that the ABS cuts in because he thought it was only supposed to work at higher speeds.

 

I suggest he trys braking gently and progressively to a halt in dry conditions, if the ABS cuts in which would increase the stopping distance then something is amiss, otherwise the vehicle is doing what it says on the tin.

41 minutes ago, CReese123 said:

also don't see how it would register below 10mph as brake locking should be irrelevant and next to nothing at such low speeds. 

 

Have you never driven on snow or ice?

 

If you did your emergency stop for real at under 10mph in those conditions you would soon be complaining that the ABS should have cut in, except you wont because it will have.

1 hour ago, J.R. said:

 

Have you never driven on snow or ice?

 

If you did your emergency stop for real at under 10mph in those conditions you would soon be complaining that the ABS should have cut in, except you wont because it will have.

 

 

1 hour ago, J.R. said:

He is stamping on the pedal, he is doing a full blown emergency stop at 5mph (probably more) a speed where the wheels will easily lock up trying to stop the momentum of over a tonne of vehicle and then complaining that the ABS cuts in because he thought it was only supposed to work at higher speeds.

 

I suggest he trys braking gently and progressively to a halt in dry conditions, if the ABS cuts in which would increase the stopping distance then something is amiss, otherwise the vehicle is doing what it says on the tin.

 

You Skid in snow / Ice, which anyone with half a brain cell is aware of. Dry conditions and abs though? I don't think you understand my point. I was driving to work  this morning and going around a sharp bend at very slow speeds, and - by this point - in dry conditions. Some clown bombs around the corner, so I have to slam to a halt. My abs cut in to the point my stopping distance is virtually non existent and I have to swerve out of the way to avoid a crash. All at stupidly low speeds. This is my reason for pondering my brake efficiency and querying dry conditions and abs. There is no reason it should kick in to that extent at extremely low speeds in dry weather in my opinion. 

 

And lastly, your assumption 5mph and probably more is inaccurate. I've not under emphasised my speeds in the slightest. 

Edited 29 June, 20223 yr by CReese123

Assuming the ABS light illuminates during startup and then turns off, the system is typically happy and working.

 

You could get the car scanned for fault codes with VCDS. If there are no fault codes, you can also use VCDS to monitor the wheel speed sensors to check for any obvious glitches whilst you attempt to provoke the problem. You could also pop to a garage and have them do a brake check to make sure they are working with the prescribed limits.

 

Your initial post states damp (rain) conditions at 20-25mph. I would definitely expect ABS to kick in at those speeds if the tyres lost traction. Given the Sumitomo BC100 review specially mentions "Long braking in the dry and wet, low wet grip and oversteer balance" it seems an entirely plausible explanation.

 

What were your old tyres? Maybe this is down to expecting premium/mid range performance from (in my opinion) a budget tyre.

Whatever the cause it certainly needs sorting, it might just be a coincidence that you've put new tyres on (the front) but something that might be free and easy for you to try is swapping the rear tyres to the front to see if this makes any difference.

 

You sound like you're old enough and experienced enough to know to take it easy on new tyres for the first about100 miles (200 if wet) and check the wheel bolts torque after the first 30 miles or so.

 

I too wonder about the new tyres in relation to the previous tyres and the rear tyres still fitted, it maybe that we're giving your new tyres an undeserved questioning but mixing old and new and different make, model and types of tyres can give unexpected results.  Tyres are an often overlooked and under valued complex component on a vehicle.

 

4 hours ago, CReese123 said:

Some clown bombs around the corner, so I have to slam to a halt. My abs cut in to the point my stopping distance is virtually non existent and I have to swerve out of the way to avoid a crash. All at stupidly low speeds. This is my reason for pondering my brake efficiency and querying dry conditions and abs. There is no reason it should kick in to that extent at extremely low speeds in dry weather in my opinion. 

You use the phrase "slam to a halt", that indicates to me an emergency stop, you say your ABS cut in and reduced your stopping distance to "virtually non existant", are you actually saying that the car stopped quicker than you wanted it to?

 

Maybe I have misunderstood, you cannot have it both ways, slamming on the brakes but actually wanting to slow progressively, maybe you meant that your stopping distance increased to virtually infinity?

4 hours ago, CReese123 said:

And lastly, your assumption 5mph and probably more is inaccurate. I've not under emphasised my speeds in the slightest. 

You have variously described that your ABS has cut in at 20-25mph, 15-20mph, 15mph, 5mph and 5-10 mph and braking harshly, hitting the brakes harsh, slammed the brakes, slam the brakes, slam harshly on the brakes, pushing the pedal to its limits, pushing the pedal to the floor, slam to a halt...............

 

In my experience under every one of these combinations of speed and heavy braking the wheels would lock and the ABS would cut in to recover the driver induced skid situation, I cannot understand why you believe that it should not or would not.

 

I can only repeat what I suggested earlier, that trying a more modulated approach is the way to sho whether the system has a fault:

 

"I suggest he trys braking gently and progressively to a halt in dry conditions, if the ABS cuts in which would increase the stopping distance then something is amiss, otherwise the vehicle is doing what it says on the tin."

 

Alternatively follow another suggestion and remove the ABS fuse and stick to your slamming on the brakes régime but please ensure nobody else is around at the time, without the ABS the brakes will lock very easily and create surprising instability, I know this because once my ABS warning light came up (it was a battery fault) and I tried harsh braking from 40mph to see if the ABS was operational or not, it wasn't and without it the brakes were very overservoed, lacked feedback and locked very easily.