Braking Problem In The Wet

[Tadass910]

Well surprisingly the brake servo test has revealed nothing other than it is working perfectly normal. Audi technical have no other suggestions as to what it may be other than to keep road testing the car. Without wishing for bad weather, I have suggested a 30 minute at motorway speed road test with wipers on may trick the car in to believing it is raining and give them the answers they are unable to find just by looking on a computer...

Interesting, wipers on when not raining tricks a car? If it’s really raining and that’s happening then I understand because it happens to everyone with ceramics it’s notmal. I been going on highway for some time like 30 mins in full heavy rain and started stop a car but it was hard to press a brake, you need to used to that just push gently few times and then it starts working fine. Don’t look for problems where you can’t find something is not there.

[Scotty C]

Well surprisingly the brake servo test has revealed nothing other than it is working perfectly normal. Audi technical have no other suggestions as to what it may be other than to keep road testing the car. Without wishing for bad weather, I have suggested a 30 minute at motorway speed road test with wipers on may trick the car in to believing it is raining and give them the answers they are unable to find just by looking on a computer...

Interesting, wipers on when not raining tricks a car? If it’s really raining and that’s happening then I understand because it happens to everyone with ceramics it’s notmal. I been going on highway for some time like 30 mins in full heavy rain and started stop a car but it was hard to press a brake, you need to used to that just push gently few times and then it starts working fine. Don’t look for problems where you can’t find something is not there.

Really - that's very helpful... thanks

[Scotty C]

Technical enquiry has now been escalated to Germany... maybe a step closer.

[zappy-chops]

Technical enquiry has now been escalated to Germany... maybe a step closer.

Hoping not, but what's the betting they come back and say there's nothing wrong. It's a feature. You are wrong Mr Customer. Can't help you without a fault code. If we can't replicate it we can't fix it. Blah, blah, blah.

[Markp]

Technical enquiry has now been escalated to Germany... maybe a step closer.

Hoping not, but what's the betting they come back and say there's nothing wrong. It's a feature. You are wrong Mr Customer. Can't help you without a fault code. If we can't replicate it we can't fix it. Blah, blah, blah.

To be fair, if there are no recorded faults and they can't replicate it (and have tried properly), there isn't much they can do...

[sasha320]

Let me know if my anecdotal testimony will help.

[Scotty C]

Technical enquiry has now been escalated to Germany... maybe a step closer.

Hoping not, but what's the betting they come back and say there's nothing wrong. It's a feature. You are wrong Mr Customer. Can't help you without a fault code. If we can't replicate it we can't fix it. Blah, blah, blah.

To be fair, if there are no recorded faults and they can't replicate it (and have tried properly), there isn't much they can do...

I agree to some extent, however I have given them an extremely detailed summary of exactly when it does/does not happen and what affects the problem and causes it to come and go so they have plenty to go on. I recommended they escalate the enquiry to a mechanical engineer within their technical team who can think outside the box and work backwards to understand what would cause the problem. It's not right and if it were a one off then id take it with a pinch of salt but over nearly a 3000 mile trip is not acceptable and needs to be resolved, not just for me but in case anyone else is unfortunate to experience it.

[Scotty C]

I have had this 'collapsing brake pedal in the wet' problem as well.

would be great to heat what Audi say - have they witnessed the fault?

So Technical have suggested it may be WFC - Wet Brake Fade Compensation. Well - looking at the information provided by them, its not, as this is supposed to assist braking not impair it... however it may answer some questions raised by others here who have experienced a different/unusual kind of braking sensation.

[sasha320]

Sounds like the system is a bit too clever for its own good...

Can’t see this issue being looked at in greater depth by Audi - certainly not on a car that is no longer in production.

[Markp]

I have had this 'collapsing brake pedal in the wet' problem as well.

would be great to heat what Audi say - have they witnessed the fault?

So Technical have suggested it may be WFC - Wet Brake Fade Compensation. Well - looking at the information provided by them, its not, as this is supposed to assist braking not impair it... however it may answer some questions raised by others here who have experienced a different/unusual kind of braking sensation.

It does say it gives you a longer pedal.

[MikeFish]

And it says it will feel strange.

Odd that we'd never heard of this feature that appears to have been introduced at facelift. And if it gives unusual or strange feeling then why wasn't it added to the manual?

[Paulm]

That's 100% what mine felt like. Feels like the peddle almost goes to the floor momentarily, then because you have pressed even harder when the brake does return you just about go through the window.

When you are pushing on and this happens its very disconcerting. Obviously not fully tested before it went into production!!

[bn8959]

I would agree with the pedal feeling definitely, so I believe in my situation it could well have been caused by WFC. But it certainly didn’t improve the braking sensation - it slammed our faces to the windscreen!

[Shoppinit]

I don't like the sound of this at all. I can't figure out why it's needed. Can it be turned off / coded out?

[Scotty C]

I don't like the sound of this at all. I can't figure out why it's needed. Can it be turned off / coded out?

Yes I imagine it can be.

As a trial, and as instructed by Germany, the dealer has switched off the Disk Wipe function on mine to see if this prevents the problems I have been experiencing. Technical in G assure me the car is still safe to drive (I have kept and printed email evidence of this in case I vanish) and braking will not be affected enough to notice. This code came directly from the factory and was not easily obtainable by the dealer.