Switch to turn on/off ABS

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sublunacy
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Switch to turn on/off ABS

Post by sublunacy »

I would love a simple switch on my dash that could turn
the ABS on/off, Right now I have been unplugging the ABS under the hood, because I usually hate using it, but on ice it's good to have....

Has anyone attempted this or have thoughts on possible wires to
tap? I deffinatly don't want high voltage/ Amps running into
the Cabin and dash in case of fire.

I'm going to check some stuff out tmrw in the light to see If I can
get a single wire, going to a switch to safely "power down" the ABS electronics, Sounds good so far
Any words of advice?
"Hows the transition look?"
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BSOD2600
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Post by BSOD2600 »

Why not use the abs fuse? or wire up something to that...

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vrg3
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Post by vrg3 »

A lot of current runs through the ABS fuse. You could use a relay, though.

I also believe there's a low-current wire running from the hydraulic unit's power supply to the ABS computer under the passenger seat; the computer uses that to monitor the state of the power supply. I believe if you interrupt that wire you can disable ABS.

When I have a chance I'll see if I can look up which wire that is.
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ericem
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Post by ericem »

or just on days with really high snow just pulse the brakes and the abs will shut off. You get some exorcise as well lol. There are occasions when it is nice to have abs like in a emergency like when you are turning and apply the brakes, instead of going straight into the guard rail, why not slow down and steer away from it??

I also heard you can slide the car into neutral (if you have a auto) and it will lock up all four wheels? Not sure if its true though. I just like the way my abs works stops fine and still lets me turn while braking that is what I am looking for.
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sublunacy
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Post by sublunacy »

yea both those ideas are suitable!

Thanks guys

There must be others wanting a similar setup,
Traction is a state of mind, haha

I think its -10 outside Im afraid to look untill I have coffee
"Hows the transition look?"
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sublunacy
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Post by sublunacy »

Ok this project is going on backburner
cause i just built a custom guage mount, and my td04 and fmic
will be here soon
"Hows the transition look?"
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BoostAddict
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Diable ABS Switch (via low-current ABS computer wire)

Post by BoostAddict »

Hi All,

I've decided to take VRG3's suggestion on tapping into the low-current wire running from the ABS computer to the hydraulic unit monitoring line in order to make an ABS-disable switch. I'm planning to use a 4-prong 12v relay and a switch like the in the ones in the pictures below:
Image

Image

I'd really appreciate if someone could confirm that the line that I should be tapping into is the GRN-BLK one at Terminal No. 32:

ABS Control Unit - Pinout:
Image

ABS Control Unit - Wiring Diagram:
Image


Thanks,
BoostAddict
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BoostAddict
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Post by BoostAddict »

Bumparoo. Can someone take a look at my diagrams above and let me know if I've got the right wire for the ABS switch?


Thanks
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sublunacy
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Post by sublunacy »

Hey those diagrams look familliar... nice one

If you cut the main power supply under the hood, the ABS should be "disengaged"
But the ABS computer under the passenger seat, should still be monitoring conditions.....Been couple of months since I looked at the wiring Diagrams thou. I think there is only 3 Large wires on the connector under the hood..... I was just going to try it! see if it works......
"Hows the transition look?"
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BoostAddict
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Post by BoostAddict »

Thanks for your reply, sublunacy.
I would prefer to stay away from cutting ABS main power supply wires under the hood.

I'd like someone to verify that if I put a relay and switch on the "Valve supply monitoring" wire under the front passenger seat I'll be able to disengage ABS.
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dman
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Post by dman »

Any update on this? Its gonna start snowing soon, this is gonna be my first winter in the car and abs switch would be nice to have.
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sublunacy
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Post by sublunacy »

It looks like your on the right track...... There are Not alot of other choices. If you knew how the Solenoids and motors work together,
the question would answer itself. But it won't hurt to try, cuase the wire isnt sheilded........I'm sorry i'm no longer interested in finding the answer, Now that i have seen a legacy engine Bay WithOut the ABS system, I know thats what i want.
---- Best of luck, After u test it, install a relay and make everyone jealous. Ps that switch is awesome. Peace out
"Hows the transition look?"
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b3lha
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Post by b3lha »

My Legacy blew a brake light bulb a while ago. The "ABS" light on the dash lit up and the ABS stopped working. I guess my ABS computer treats a blown bulb as a malfunction and shuts down. When I replaced the bulb, the ABS started working again.

Maybe you could mess with the wire that tells the computer that a bulb is gone. I don't see any wire like that in your diagram, so maybe your Legacy has a different system to mine.

The car actually seemed to brake better with the ABS off.
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Arctic Assassian
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Post by Arctic Assassian »

I took my fuse out for the winter. ABS wont let me stop on ice I fucking hate it.
Kickin' it old-school.
flatoutfred
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Post by flatoutfred »

ABS= anti breaking system

On any surface, these old ABS system sucks. Any average driver can stop the car better than they do.

Every times I buy a used car with that crap, the first thing I do is disable it.

I used to work a while ago at hertz rental, one day we've tested the abs with sunfire, taurus, explorer, crown vic, etc.

One pass on a icy road with abs, hit the brake at a particular marked point and waited till the car stops.

Second pass, same thing but without the abs.

Most of the guys were stopping, in average, 20 to 30 feet earlier without the ABS.

On the other hand, the newer cars have a better ABS technologie. For example, my Golf TDI has a ABS system and it woks great, it saved front bumper twice already. It engages at the very last moment, so you can still hit the brake and try to stop the car until the wheels are about to lock. Not like the 2002 taurus, if you're on a ice patch and hit the brake, the pedal hardens and you have to let the ABS do his job or I should say let him try to do his job.

My 2 cents
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Legacy777
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Post by Legacy777 »

The thing to note is that you're talking about ice/snow. I would tend to agree with you for controlled environment tests. However for wet roads and dry roads, DURING "PANIC" type situations, the ABS system will work and most likely brake better then you will.
Josh

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