Hi, Honda Folks. I'm hoping someone here might be able to help me out with a real hair puller. I've got a '93 Del Sol 1.6 with a crank no start and code 15 - Ignition Output Signal. I have no spark back to the coil and the tach doesn't budge when cranking. After brief testing I assumed the igniter was the likely culprit and replaced it with OEM Hitatchi #e12-303, but this did not fix it. According to the owner the car was running fine, was parked for five minutes while they went into a store, and when they came out it wouldn't start.

I'm going to try to accurately list everything I've tested.
-Tested coil primary and secondary resistance (0.8 ohm & 16k ohm).
-Tested CKP, CYP & TDC sensor resistance (~360 ohm @ each)
-KOEO voltage @ igniter pins that connect to coil and @ coil (~12v)
-KOEO voltage between ECM pins 21/22 & 26(gnd) (~10v)
-Tested main relay:
>voltage applied @ pins 6/8 continuity across pins 5/7
>voltage applied @ pins 5/2 continuity across pins 1/3
>voltage applied @ pins 3/8 continuity across pins 5/7

Now, my thinking is that since my tach doesn't move when cranking (I assume it should?), and the tach recieves its signal from the ignitor which has been replaced, that the ECM would be my likely culprit. Are there any inputs to the ECM involved in its operation of the igniter that I need to check? I have disassembled the ECM and physically checked it for obvious signs of component failure and found none, and I know from experience that ECMs rarely fail unless physically damaged or shorted. Maybe I'm overlooking something bleeding obvious or my understanding of the way this system operates is flawed. I'd appreciate any advice.