No VSS signal on 2001 Astro

I've got a 2001 Astro cargo van that I cannot get a working VSS signal to save my life.  I went to the ECM, pulled the 'black' connector and found the green wire with white tracer, tapped in and could not get my CCS-100 to work.

After troubleshooting all the other wiring connections & switches that I could without driving I was left with the VSS lead. I checked it on my Fluke ScopeMeter and sure enough, there is no pulse whatsoever. However, the speedometer works perfectly.

For grins I moved my tap to pin 1 on the black connector which also has a green w/white tracer and same thing, just some noise, around 50mV but no pulse with driving.  I have verified my tap is good, the continuity is perfect from the ECM to the Molex connector on the CCS-100.

Any ideas???  I'm stumped.  I have no pinout for the ECM and Google isn't turning up much either.  I've got a 5 hour drive on Monday and sure would like to get this working.

Thanks

Ok, I've got some more info now.  I went to my local Chevy dealer and they were able to help some.  They gave me pinouts of all the ECM connectors, I found another VSO (vehicle speed output as Chevy calls it) on the Blue connector, pin 15.

However, it appears the pulse may be too fast, On my meter I'm seeing a 150hz around 5mph. If my calculations are correct, thats 108,000 pulses per mile which is way too high.

Should I just give up on the VSS and go with the mag sensor?

FWIW - I finally got it working.

I found on the pinout chart that pin 4 on the black connector is also a VSS output, moving the sensing line to pin 4, dark green wire finally got it working.