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Discussion Starter · #1 ·
Been searching for a while and i found a few answers but i wan't to know if there are any other ways to disable abs. Currently i have a switch wired up to my abs fuse but i dont like that cause i cant controll the cent diff. Ive read somewhere about taking off an abs sensor from one corner of the car but i want to be able to turn it on and off quickly for diffrent conditions. Any ideas?
 

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I work as an engineer in the ABS world and I tell you that it is pretty much impossible to turn it off unless you just cut power to it. That BOSCH unit is almost impossible to break into because of the way they manufacture their ECU housings. I have done it a few times and the unit is pretty much shot after you do it.

I was thinking of this a lot too and I have a few of these units at work. I will ask a few guys that benchmarked it how they control the unit. Maybe they will be able to tell me if we can break into the power wire and maybe run a switch off of there so that you kill the power to the entire assembly. However, I am sure that a "disco" full of lights and fault codes will appear.

Let me check this out and I will get back to you.
 

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Discussion Starter · #5 ·
Mainly for use in gravel and snow to perform the scandanavian flick. Also in snow and gravel you can slow down faster by locking up the brakes and making piles. Also lately in the rain ive been sliding out a lot lately and im sick of having to pull the ebrake so i dont go in the ditch because the abs still makes my car go in the direction its pointed.
 

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When we design them for development trucks we actually make it so it turns off when you hit the TC off button. The reason being that the truck will stop faster on gravell and in some situations snow because all of the matter piles in front of the tire and causes the g graph (deceleration) to be higher than on dry pavement. Pretty cool.

Anyhow, still trying to gather info about breaking into the BOSCH (I don't work for BOSCH so it is a bit harder hehehe).
 

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I added a switch to my 02 wrx for the same reasons. It was a fairly simple install. I put a toggle switch inline with an abs wheel speed sensor. It worked well on a wrx but I don't know what that would do to a dccd. I could dig out the wire diagram if you like.
 

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can you guys not simply pull the ABS fuse?

that's what i've done in my RS and my WRX....

works great :)

yes you have an ABS light
so what. you want it off right????

Jamie
 

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You can pull the fuse but it would be cool to just be able to turn it off while you are in the car.

I did more research on the BOSCH unit and if I could break into the power line and create a switch. However, I found out from guys at work who work with the ECU modules that it is a very bad idea. These new units set soft and hard codes when something goes wrong such as a speed sensor not working properly or the power being disabled. The soft codes are no problem. The hardcodes will get you. You can't get rid of them even with the OBDII.

Anyhow, I am sure making a switch to create a "break" in the fuse would be possible. The fuse doesn't set off any hardcodes. Now, I hate anything to do with wiring and electricity so I have no clue how this would be made but am sure that it wouldn't be that hard.
 

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I posted a similar question a couple of years ago. My interest had to do with track days. One way to spin "safely" on a racetrack has to do with locking all 4 wheels once you see that you are sliding in a safe direction.

With the 4 wheels lock, the car will continue in a straight line, regardless of which way it is pointed.

I was told at the time, that by removing the fuse, I'd also be disabling the electronic brake biasing. I don't know if thats true, but I decided not to pursue it.


Don
 

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I would highly drop the "remove the ABS unit" option. Pointless.

donmei, I am not sure what you meant with 4 wheels locked the vehicle will keep in a straigth line. That doesn't make much sense to me because if all 4 wheels are locked the biach of Inertia will take the direction it wants.

I think the ABS on the STi is awesome because the car has so much grip that your brakes are working very hard to lock up. They can lock up but not easily hence the ABS is only on for a second or two. It is not very agressive, which was a great surprise to me.
 

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mgizzle,
You say you don't understand what I mean, but you use precisely the word that helps to explain it.

Inertia. A locked wheel has NO directional control. i.e. if a wheel is locked it cant "steer" the car. It has the same resistance going in all directions.

So . . it has been common practice on a race track that if you were spinning and you saw you were spinning in a safe direction (by that I mean a safe direction of travel, regardless of what way you're pointed) to then make sure you STOOD on the brakes. With all 4 wheels locked the car will continue on in a perfectly straight line.

In contrast, a spinning car with abs could suddenly start to roll while facing backwards and at that point appear to suddenly turn right out back into traffic. I'll try to find some vids on youtube to demonstrate, but botom line is that the ability to lock the wheels is a plus on a race track from a safety perspective.

Don
 

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Discussion Starter · #15 ·
I Already have a Switch hooked up to my ABS fuse but when i turn it off this causes the Diff controll to go full rear and that is not what i want it to do all the time(Which would be fine for the road which only solves half my problem) Mailnly i want this option for the gravel and winter. as Stated in the above statement that is my purpose to skid in a safe direction incase i freeze up and don't reach for the ebrake in time!! Also the ability to controll the cent diff with abs off which is not possible with the switch set up.
 

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Yeah, and in snow and gravel, you may want the diff to be completely locked. I know in daily driving in the snow, the understeer that comes from a locked diff is nice on the highway.

Don
 

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you could always tap a switch into the fuse... flip it to break the circuit, back on the allow the fuse to do it's job. run the wires long and mount the switch in the cabin.
 

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Looking at the serice manual you could always tap a switch on the ground or the power wire.
 
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