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It will work fine for this test, thats all I did and had TP showing 0-200kph on D2 from a 12v square wave.

ok i got a chance to do some testing and the pcm is doing as it should
i even get a flicker on the VSS guage in TP when tapping D2 to 12v


but still nothing with the VSS so can anyone name these wires


EG: blue= pink/blue-12v
green= purple/white-sig to D2
black= black/white-ground

the speed sensor is ok but it not the way i was thinking

D2 pad is 0v and the inverse pad is 5v

put 12v on D2 pin i get 5v on pad and 0v on inverse pad
so the pcm is doing its thing

but when i play with the VSS and a LED the VSS is switching to ground
so its trying to pull D2 low not high as i was thinking it would

Thats actually the way the factory diagram shows it, as a ground switch Will work out a fix for it If you want a quick fix try a 1k pull up resistor between the blue 12v and green signal wires, should get it working.

haha so its not me

if the inverse pad is pulled low will that make the D2 pad high

or is it D2 going high pushing the inverse pad low




would these 2 spots in white be of any use

Those two resistors are important Turns out U5 is not a buffer chip but looks like an op amp setup as a comparator with hysteresis. And was missing a pull-up resistor also. This should work a little better I hope...

Problem solvered

haha i will give it a shot later tonight



EDIT: i can confirm working on the bench with a VSS

a in car test and im over the moon


vl400 now you really are the man

nice work all involved!

Awesome, makes conversions a little easier now Looks like the PCM is happy with it too, no drop-outs or spikes in there.