Lost spark

[Ragboater]

2001 200 LZ HPDI. Started losing spark intermittently. Now dead. Several mechanics failed to diagnose the problem. I have done the following: No codes have been thrown. I have swamped out the crank sensor, Pulser coil, ECU, Triggers and coils to good motor. they all ran the good motor perfectly. The good motor runs fine with the stator unplugged. I changed the ECU harness.
I have no voltage drop from the fuse blocks and have good grounds. I isolated the boat with a remote starting harness. I even cut the white kill wire. All the coils are getting 12 volts at the coils, but the ECU will not fire the coils. Something is not letting the ECU fire the coils. I need some help please.

[rodbolt17]

do you understand how that TCI system works?

[Ragboater]

Coils are grounded through ECU, vs a CDI which charges the coils.

[rodbolt17]

there is no CDI on an HPDI.
HPDI uses a TCI ign.
the coils have 12v on the primary and the transistors in the ECU open and close the circuits.
the pulser coils trigger spark and injection.
no 12V on the coils no spark.

[99yam40]

2001 200 LZ HPDI. Started losing spark intermittently. Now dead. Several mechanics failed to diagnose the problem. I have done the following: No codes have been thrown. I have swamped out the crank sensor, Pulser coil, ECU, Triggers and coils to good motor. they all ran the good motor perfectly. The good motor runs fine with the stator unplugged. I changed the ECU harness.
I have no voltage drop from the fuse blocks and have good grounds. I isolated the boat with a remote starting harness. I even cut the white kill wire. All the coils are getting 12 volts at the coils, but the ECU will not fire the coils. Something is not letting the ECU fire the coils. I need some help please.

Rodbolt did you read his post?
seem he has covered everything you have mentioned already