Those sensors are inside the carriers and unaffected by clag/dust/particles etc. Sensor lives where the black wire is coming out to the left of the brake rotor.

Ice mode results from a ABS software bug or accelerometer data spike outside of programming parameters (deceleration rate or whatever).

Triggered by different coefficient of friction and initial deceleration rate caused by slicks/oversizing of tires.

 

oversizing of front , rear or both / either tyre ?

 

^ Holy shit! Have you done anything to counter this problem ?

 

I experienced ice mode brake failure in a completely bone stock 900 mile driven 997.1 GT3RS on N spec Michelin pilot sport cups (ie completely stock wheel and tire package) at Hallett. This is also a bumpy track. Rock hard pedal, no stopping whatsoever.

I am a reasonably experienced amateur racing driver (6 years, 9 race weekends a year racing open wheelers and spec miatas) and this experience convinced me to get rid of the RS. My car and I didn't get hurt because of luck where it happened to me and the fact I drive street cars on the track like an old lady going to church. I assumed that Porsche would have fixed this by now. This is a serious design flaw in a car that is marketed as a track ready sports car.

 

Glad you are okay. And now I know about Ice mode!?!! ekkk. Another reason to use a Cup car for the track.

 

is there any such thing? "a track ready sports car" I sold my 2010 GT3 for that very reason. My opinion, if you want race Porsches buy a cup car, if you want ABS brakes that are functional under race conditions buy 996 Cup car which has steel rotors. Again, I am just a SM Miata guy and wouldnt get in the deep end of the pool racing ALMS GTC or Grand Am.... I guess I have finally outgrown abusing my street cars on the race track.

 

What i find terribly stupid on all this is the logic followed by the ABS system!
If something goes wrong for whatever reason, the ABS should NEVER prevents the possibility to stop the car in the shortest possible time.
It is much better locking the wheels than not breaking at all!!
It is like saying on an airplane something goes wrong and the flight-computer switches all off...goodbye to all...

Mach01 is with us today and this is GREAT!
But this problem is very serious, someone else could not be that lucky next time!
I am stunned that Porsche does not take in consideration this issue in a very serius way!

As far as I am concerned from now on I will always take the ABS's fuse off when on track, at least I know what I am doing already...

 

I dont know anything about ABS failure on the race track with carbon ceramics but there seems to be at least one other inherent flaw with the new RS - I have heard repeatedly about clutch and flywheel failures all over the country. First couple of stories I chalked up to driver error - mechanical over rev on the down shift. But I know of at least 10 failures here in Florida. The whole assembly comes apart and destroys the bell housing, clutch & flywheel. Porsche has not been standing behind them as clutches are excluded from warranty in most cases, but I know guys who have been through two clutches already. I have had single mass light weight flywheels and clutch assemblies in previous 911s without any issues and I have also over revved dual mass clutches and spun the timing ring on the flywheel as a result of my own driver error but the new RS seems to be having frequent failures in this area.

Maybe you guys have discussed this in another thread.

 

Happened with me once at Dubai Autodrome, was doing 250km/h before braking.

Car setup was rear P zeros and front semi slicks (oem cups) as temp solution. Since no semi slicks available yet and I had rear puncture.

Am never goin to the track without full set of semi slicks again..

 

Mach01, glad you are OK.

I would like to learn more about this problem.

I've seen accomplished drivers (Including the #16 in the above incident.) that reported ICE mode. Guys I ran with that are smooth and fast, certainly no hacks.
Personally I have not had it happen yet. I do know that if I get only 25% braking and I need to give it a full second to recover brakes into T17, I will not make it. I doubt anyone could.

Pagid green with PCCB and R6 should all be within factory spec, yet I've never had ICE mode yet with steel brakes, slotted front rotors and Pagid R29. So I don't think it is due to slotted rotors.
Maybe it needs super high grip like slick, or in this case super high grip on the track with good sticky Hoosiers to replicate that kind of grip? Still a terrifying prospect not knowing what exactly causes this.