what voltage should i be getting out the yellow/grn ignition signal wire at the ecu. i am only getting .08 volts while i am cranking the engine.
it is on a obd1 b18c

 

Is the ICU disconnected from that wire? I'm not sure but I think the ECU simply closes & opens that wire to ground to fire the ICU. If it's connected but still no voltage, maybe it's the ignitor's (ICU's) fault.

 

with the wire off the icm i have 10 v at the icm, i have .08v coming out of the ecu while it is cranking. i am not sure if the ecu sends a signal(voltage) to icm that triggers the coil the fire or what. i have power to the coil, it just won't fire.

 

With the Yel/Grn ICM trigger wire connected to the ICM, and engine cranking, that line should most definitely pulse.

The ICM is probably acting like a 'pull-up resistor' to the Yel/Grn wire - meaning that without the ICM connected to it, you may not see the wire pulse at all even though it actually is.

Had you checked the ICM trigger wire with the ICM connected to the ECU to see if it was pulsing at all?

 

i am gonna check that next. what should i see at the yel/grn with the wire hooked up to the icm?