[Richard]

Thanks for the clarification. I wish I knew more Allison specifics, but I can only help with general problem solving and you have done a lot.

The fact the 2nd pad won’t light up when “hot” wired is very concerning. Before drawing any conclusions, your reference to PIN numbers doesn’t jive with the Allison schematics I have seen on line, which have Alphabetic designators. I am probably not finding the right schematic. My point is that the schematics for the shifter probably need to be confirmed on the 12V inputs before concluding both will not light up.

In my own shenanigans, when I get “lost” in problem solving, I find it’s time to go back and confirm what I think I know.

I have found a bunch of threads on the interweb about the Allision pad not lighting up. All of the ones I have read were all power to the system caused. Your test light to the front was a GREAT way of confirming you had power.

In the three visits by the Allison techs, is it correct the only shift pads tried were your original and the rebuilt replacement? None of the Allision techs had a test shifter to evaluate?

If we were close, I would yank my shift pad and bring it over.