Car started losing power while driving, tach went to 0 even with the engine still running, then eventually died. Fuel cutout light came on. Checked the inertia switch, it was fine. Fuel pump wouldn't come on. tried the diagnostic jumper, still couldn't get it to come on. Jumpered out the main relay, car starts up and runs fine. Thought the PCM was the problem, changed it, still have the same problem. Something is obviously sending a signal to the PCM to not allow the main relay to energize (since I jumpered that out and the car ran just fine). What (if any) are the other things that can give you a fuel cutout light and not let the main relay energize, besides the inertia switch?

Thanks for ANY ideas you can help with.
Steve