Traction control using abs sensors questions

Discuss which Sensors work best with these ECUs and share how you are using inputs and outputs
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Zed.
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Traction control using abs sensors questions

Post by Zed. »

Hello.

quick background (& first post :oops: ) I'm building a 1991 Mk1 Mx5 with a Vauxhall Xe and S100 ecu* with too many bad ideas :lol:

I've read and searched these forums over a few weeks but not found anything about this....

I'm hoping to use oem abs sensors and reluctor rings to supply signal for tc, launch and speedo but wonder if theres an optimum tooth / trigger count or if any (sensable?) number would work?

the 'rings on the car are 44 tooth iirc but can easily be halved or quartered to lower tooth count.

I'm intending to use 4 Vauxhall / Siemans orange relays / signal converters as I've found mentioned on these boards (thankyou for that)

Thankyou for reading.

Rich.



*started with a cheap S40 but tripped over a cheap S100 and had ideas of grandeur :lol:
stevieturbo
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Re: Traction control using abs sensors questions

Post by stevieturbo »

Seems the DTA can handle up to 60 teeth now, so you might be ok without removing teeth

What is the nature of your ABS sensor, and are you also wishing to retain ABS operation ?

DTA wants a square wave, but if it was a hall sensor already, you might be lucky and be able to tap into the trigger wire. ( this may or may not make the ABS unhappy though )

Or as you suggest, I think the Vauxhall "relay" option is one to try. And it is something I'm considering myself for a future project.....if I ever buy the actual car lol.
Many years ago I had used a Subaru trigger wheel, but at the time I think DTA only accepted up to 40 teeth so I did have to remove half of them. Looking at the current software it says up to 60 teeth
Rob Stevens
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Re: Traction control using abs sensors questions

Post by Rob Stevens »

regardless of teeth count you have the option to adjust the tyre circumference and therefore fool the ecu even if you have too many teeth :)
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Zed.
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Re: Traction control using abs sensors questions

Post by Zed. »

Thankyou for the fast replies, if theres no issue with tooth-count then I'll probably be lazy and not remove any although if it causes a problem I suppose its not to hard to alter in future.
stevieturbo wrote: Sat Jan 21, 2023 5:34 amWhat is the nature of your ABS sensor, and are you also wishing to retain ABS operation ?
Mazda use 2 wire VR sensors, they read from the side and seem to be a reliable system (when new :lol: ) my car didn't have abs and I'm retrofitting later components to run these sensors - started with the drivers front to run a Stack speedo but the different ecu has opened up the option of traction control

Image
unfortunately the hub / wheelstuds are a fair distance from the uprught so mounting a conventional proxi (hall effect) sensor would need some thought - I have 2-piece discs so could use the 6 disc mount bolts but wonder about heat issues?
Rob Stevens wrote: Sat Jan 21, 2023 6:14 am regardless of teeth count you have the option to adjust the tyre circumference and therefore fool the ecu even if you have too many teeth :)
that also could work, not like the ecu supplies a vss to a speedometer so it doesnt need to be 'accurate' for roadspped.

Rich.
stevieturbo
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Re: Traction control using abs sensors questions

Post by stevieturbo »

You could mount a hall sensor directly onto the same trigger wheel. I would not try and use the wheel studs, too low resolution with only 4/5 teeth

Although at the rear I used to use ( well still do as well ) the 8 disc bolts without issue.

Due to other electronic changes I made ( not DTA anymore ), this caused signal to be less reliable, so for traction control etc I now use gearbox output shaft/prop speed instead which has actually proven a better setup for me.
I do still log both driven wheel speeds though at 8 teeth each, and a front left at 11 teeth ( was 44, removed 1/3 as DTA could not do over 40 at that time it was first fitted )
stevieturbo
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Re: Traction control using abs sensors questions

Post by stevieturbo »

And although it's less likely on an older car, might be worth checking signal with a scope first before you get too tied up.

A lot of car ABS systems do use a 2 wire setup, but they're an odd current sensing setup, where there is 12v power down the two wires, but changes in current as the teeth pass are what are deemed the trigger, as opposed to either a regular VR sine wave, or Hi/Lo Hall setup.

Not sure how these sensors would respond in an un-powered state, but may not be usable.

This description isn't bad. Such a dodgy accent though ( he's local, but I don't actually know him )

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Zed.
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Re: Traction control using abs sensors questions

Post by Zed. »

thanks again, I see me getting lost in a youtube wormhole :shock:

I'll do some reserch to check the type of sensor, maybe I'll try a proxi-sensor in the hub assembly against the reluctor ring to see if it'll read, if so then maybe I'll fit them as it'll simplify the wiring.

Rich.
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Re: Traction control using abs sensors questions

Post by Alex DTA »

You will be fine with the two wire sensor and the Siemens converters.
I used the converters on my Audi with 43 teeth, and had no issues at 150 mph.
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Zed.
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Re: Traction control using abs sensors questions

Post by Zed. »

thankyou for the reply, okey, thats the direction I'll head in, scrapyard diggin on the weekend for some Siemens converters things and then I'll have to think about knitting the wiring to connect it all togther (thats a bit of an issue as the cars been in bits for a few years and most of the progress involves buying / hoarding parts and sub-assemblies but not actually bolting stuff togther :oops: )
Alex DTA wrote: Mon Jan 23, 2023 4:11 am I used the converters on my Audi with 43 teeth, and had no issues at 150 mph.
thats reassuring, but I've geared the car for ~115mph as I'm not brave enough to go faster :lol:

Rich.
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