Read VR Wheelspeed sensor without screwing up ABS Computer

Hello,

I want to read the wheelspeed sensors of my RX-7 FD with my haltech elite 2500.

The Elite is capable of reading VR wheelspeed sensors, but splicing the signal and feeding it directly to the ECU will screw up the ABS, because of the voltage potential between the ECU and the ABS computer.

I think a signal conditioner will not change this, also it's overkill because the elite can read VR signals and needs no conversion to square wave.

In the internet I found an old manual from adaptronic, they used 1:1 isolating transformers(small PCB version like the Bourns LM-NP-1001 Series). THe transformers clearly fix the issue with the potential difference, but will introduce some impendance to the signal-wiring. Will this impendance cause also issues?

What are your solutions for this problems?

regards

Bastian

The spi's are a precious resource on the elite series, you only get 4 of them so converting to a single wire digital signal has its benefits. Im about to do the same thing with my FD, the max9924 vr to hall signal convertor chip is the heart of just about all commercial signal conditioners and if you look around they can be had for cheap.

There is the max9926 version for dual signals also. I grabbed one from these guys below, it's configured and ready to go and less than 1/4 the price others are asking.

If I weren't going to use a signal conditioner I'd probably try and run an additional sensor (hall). Have heard from someone with plenty of experience that trying to split the vr signal just doesn't work. Not an expert by any means but spent a fair amount of time researching this

https://sirhclabs.com/product/vr-to-hall-sensor-converter/