Hondata

I am trying to run the signal from my E30 cluster which im pretty sure is a 12v square wave form. Is 12v ok to run to the Kpro VSS input or do i have to find a way to convert it to a 5v signal?

Probably not a good idea. The KPro input is protected but there is a pull up to the ECU 5V so you will start to put a 12V waveform on the ECU 5V supply.

It really likes an open drain input where the input will ground the KPro Vss input. Hence the 5V pull up.

Any idea the best way to convert this input to a usable speed signal input?

A resistor and transistor as open drain will covert the signal. There may even be pre-made modules to do this. Selection is up to you however - I'm just here to tell you it needs to be 0-5V.

Hondata wrote: Sun Aug 29, 2021 11:34 am A resistor and transistor as open drain will covert the signal. There may even be pre-made modules to do this. Selection is up to you however - I'm just here to tell you it needs to be 0-5V.

will the ECU have trouble if the voltage is below 5v? like if it fluctuates between 3.5-5v but still grounds to 0v will that still work?

It should be < 0.5V and > 4.0V for every pulse.

Ever find a off the shelf solution for this?

DriverMikeD wrote: Tue Nov 22, 2022 8:45 pm Ever find a off the shelf solution for this?

I'm wondering if this will work. I'm looking to feed the E36 VSS signal to my KPro in a PRB ECU.

https://www.diyautotune.com/product/axm ... LrQd4Ls1zA