99 Accord LX immobilizer?

I’m trying to trouble shoot a no fire scenario for a 99 Honda Accord LX. The owner says the car ran great, was parked and then would turn over, but not start. I discovered a no fire situation. While trouble shooting, I was able to determine that proper current is making it to and from the coil. However, no spark is generated from the coil. We did swap the coil, ignition solenoid and igniter. The same situation was present. Apparently, there is no ground, thus allowing fire.
Since I don’t know Accords well, I didn’t want to possibly overlook something obvious.

My cheapo scanner will not communicate at all with the PCM. I Know the scanner works. Bad PCM, or possible security issue?
Would a bad crank sensor be a possible cause?
How are factory security systems set up with Hondas? Do they generally disable spark via the PCM or fuel, such as the injectors?
Any thoughts would be appreciated.