1227747 to 16197427 Conversion PCM Swap with Wiring Pinout Directions!

[CDeeZ]

What is the normal input from the VSSB to pin F13 on the '7427? Some sources say 2k PPM, but others say 4k PPM. And when do you need to set the "Output Speed not from DRAC" flag?

Brian,

I think it depended on your original application. I believe 4K is the more common, but 2K is doable, and then check that flag "output sped not from DRAC"





As far as the P/N switch: Since my C1500 was originally a 7747 ECM, it had a P/N switch on the end of the column, under the dash, inside the cab. When I still had the 7747 in there, I hooked up my laptop and when I unplugged the P/N switch entirely it showed as being in "Drive" all the time that way. (T-56 here BTW) I've left the P/N switch unplugged since swapping to the 7427.

The '7747 is a 2K PPM VSS. The '427 is happy with a 2K PMM input to pin F13. The only time I needed 40 pulses / revolution was for an electronic overdrive transmission conversion.

dave w

Dave, how exactly did you do the 2K PPM vs the 4K PPM???