OK so I am using a NV3500 Trans on my TPI build. Issue, NV3500 is a 40 PPM VSS, 7730 ECU needs a 4000 PPM. The 90s DRACs out of suburbans turn 40PPM into 4000PPM. Im just not sure how to wire it.


So the Blue wire gives the pulse I need. The wiring for the 7730 ECU is wire B10 and B9 go to the VSS. So I know the green,purple from the drac go to the VSS, Black/brown go to the Ground and Key 12+, connector 2 is for CC so i dont need it, White wire is ABS so not used and other brown wire is 2000pulse So i dont need it and Blue is the 4000 I need so it will go to the ecu but where do I pin it in at? I know I cant just slit to both wire I assume one wire from the ECU powers the VSS and the other recives the signal but I dont really know how the VSS works.

 

Need to use the 'To ECM pin A10 (Brown)' wire and run it to pin C6 on the '7730 ECM.

Then zero this flag/bit in the BIN: Mag VSS, that will tell the ECM firmware to use the 2K PPM optical input instead of the 4K PPM sine wave (magnetic) input. More info on this flag:

It is location $18, bit 6 of option word 3.

RBob.

 

How do you know unused pins do anyways? what else am I missing out on with the unused pins on these ECM?

 

Been in this stuff for a long time...

Can control a second fan on F8, use an oil temperature sensor on F12, an external knock filter on B8, may be some I missed, but they are used in $8D.

There is a note upon using the optical VSS input. The pulses streams that the ECM creates and outputs will not be available. They are only available when using the magnetic VSS input.

I didn't mention it earlier as your application doesn't look like it will need it. But others reading this may be using a different vehicle.

RBob.