Another distributor question

The power coming to my coil does not go on and off when cranked. I'm thinking either bad trigger in the distributor or the ECU. First is there a way to test to see which is bad? Second, can I replace the trigger in the dist. or do I need to replace the distributor?
This is in a 93 xj sport with a 4.0.

Thanks for any help

Jim

Have you checked your crankshaft position sensor?

No haven't checked it.