Is there another vehicle available with a JTEC PCM to try your scan tool on, to verify it is capable of reading this one?
I will suggest basically starting over with diagnostics. Start checking power and ground to the PCM itself. If the scan tool would communicate with the PCM, I want to know if there is RPM showing while cranking.
When wired and working properly, the PCM will turn on ASD relay a couple seconds when key is turned on to prime the fuel system, then PCM turns ASD relay off. When cranking, if no crankshaft sensor signal is detected by the PCM it has no reason to turn the ASD relay back on; PCM thinks the engine is not being cranked. When crankshaft sensor signal is not present during cranking, there will be no spark, no injector pulse, and ASD relay will not be turned on.