Random question on the ABS fuse

[renfield90]

If I pull this fuse, what gets disabled in addition to ABS? Do I lose VSC and EBD as well? I'd greatly appreciate feedback from people who have pulled theirs. Thanks.

[Arsenal Autosport]

Why are you trying to disable the ABS? For track duty or some other reason?

I have not done so, so I can't offer any insight - but I would assume that you would lose any kind of stability control that relies on the brakes.

[renfield90]

Two words: ice mode. It's a safety issue if my brakes quit working and I'm pointed at something more substantial than a cone.

[Arsenal Autosport]

Is this an issue that you've experienced in the FR-S?

It's a known problem in 997 Porsches (usually with staggered, R compound tires and hitting the brakes with some side load in the car) and I've experienced it once in a Boss 302R as well - but never in the Scion. I'd be interested to hear about it if it's an issue.

[xwd]

Originally Posted by renfield90

If I pull this fuse, what gets disabled in addition to ABS? Do I lose VSC and EBD as well? I'd greatly appreciate feedback from people who have pulled theirs. Thanks.

Yes you lose everything. There are two ABS fuses, one is 25A and the other is 40A, so they power quite a bit of stuff. The car isn't really meant to be driven without the system, at least on dry pavement. I've autocrossed on a fairly bumpy lot recently and have not experienced ice mode at all. People who left foot brake however have experienced issues, but it's likely related to throttle+brake at the same time. Just disabling the EBD via the "pedal dance" trick to put the car in maintenance mode makes the car go into ice mode more often.

[renfield90]

I do a lot of trail braking. I get it a lot less if I brake in a straight line, although I was in a straight line last weekend when I hit the brakes and DNF'd my run...

Speed of brake application seems to play a factor too, although again this weekend I was already deep into the brakes when it literally popped back on me and became rock hard.

[Sam Strano]

Ice mode is not a random thing. It happens when some series of events happens that makes the car think you are on a low grip surface. And the brakes don't just go away, thought he forces are lessened to about .3g when it's happening.

FWIW, I know at least two of us that have no ice mode issues what so ever. I also know that many folks have issues with it in all kinds of cars, and I don't in the same cars (Mustang, Corvette, F-bodies).

[OrbitalEllipses]

Originally Posted by Sam Strano

Ice mode is not a random thing. It happens when some series of events happens that makes the car think you are on a low grip surface. And the brakes don't just go away, thought he forces are lessened to about .3g when it's happening.

FWIW, I know at least two of us that have no ice mode issues what so ever. I also know that many folks have issues with it in all kinds of cars, and I don't in the same cars (Mustang, Corvette, F-bodies).

So it's the nut behind the wheel, combined with the nut's particular car setup?

[renfield90]

Originally Posted by Sam Strano

Ice mode is not a random thing. It happens when some series of events happens that makes the car think you are on a low grip surface. And the brakes don't just go away, thought he forces are lessened to about .3g when it's happening.

FWIW, I know at least two of us that have no ice mode issues what so ever. I also know that many folks have issues with it in all kinds of cars, and I don't in the same cars (Mustang, Corvette, F-bodies).

I spent the last 7 years surprising autocrossing and tracking a car with no ABS. I guess it wouldn't surprise me that there's braking habits that may not play well with a commodity ABS system, but come on - this car has "sport" in the name. It shouldn't freak out because I put sport tires on and drive it sporty.

The Boss 302 Laguna Seca I drove for the first two months of the year gave me zero issues with ABS, and neither has any other car I've ever driven (too many to list). Not convinced this is all on me. If someone has concrete driving suggestions to offer, I'm listening.

[ChopsMcgraw]

Originally Posted by renfield90

I spent the last 7 years surprising autocrossing and tracking a car with no ABS. I guess it wouldn't surprise me that there's braking habits that may not play well with a commodity ABS system, but come on - this car has "sport" in the name. It shouldn't freak out because I put sport tires on and drive it sporty.

The Boss 302 Laguna Seca I drove for the first two months of the year gave me zero issues with ABS, and neither has any other car I've ever driven (too many to list). Not convinced this is all on me. If someone has concrete driving suggestions to offer, I'm listening.

Hey Manfred-

I had issues with Kevin's car on the Z2's with hard pedal, as did Clint at the Bondo event. I can commiserate, but have no solution for you other than don't stab the pedal and turn-

[renfield90]

Thanks Elliot. Stab and turn worked great on the Celica...

[xwd]

It's definitely a combination of system and technique. For instance Bill Cook and his previous drivers never experienced it but at Dixie Mike King drove his car and had it happen all the time. Do you guys left foot brake? That seems to make the problem worse but may just be an effect, I had a tendency to stab the brakes more when I LFB.

I have read somewhere the ABS logic may take into account how fast you are braking, it might treat a quick stab as panic braking and trigger the ABS.

You can search for "pedal dance" and try it. Using that mode to disable EBD helped the track guys with trail braking, but in general just made ice mode kick in more often in autocross.

Are you using the stock pads?

[Sam Strano]

Physics dictates that you can't stop and turn at the same time, not without lessening the pedal pressure as the cornering force ramps up, which is really trailbraking. Braking hard while trying to turn is not trailbraking and no car will be happy about that because you are asking too much from the tires.

This car has limited droop, and I suspect that some folks are managing to be so hard on the brakes when turning that the inside rear locks, and that will ALWAYS give you ice mode because there isn't any other reason normally that would happen.

A Mustang is something I'm familiar with, and guess what.... plenty of folks complain about the same thing on those. Corvettes too. I have issue with none of them.

The Mustang has a lot of inside droop, and a solid axle... and a lot of weight on the nose that makes it less likely to tolerate being stuffed in a corner on the brakes hard enough to cause you issue with the rear. But still folks have it happen because they just flat overdrive the tires.

The car doesn't freak out if you drive it sporty. Mine doesn't. Andrew's doesn't. This is a driving thing I'm sorry to say.

[Sam Strano]

Originally Posted by ChopsMcgraw

I can commiserate, but have no solution for you other than don't stab the pedal and turn-

This. ^^^

It's a no-no with or without ABS.