Any Duramax FICM experts in existence?
I've got an LB7 FICM on the bench that I'm trying to operate with a non-GM ECU and I'm trying to drive 8 injectors from an ISB.
It isn't firing injectors, I'm monitoring the CAN channels and I've got two CAN messages that I don't have definitions for.
I'm sending low side .5msec pulses for all 8 cylinders in firing order, I measured LCR on all 8 injectors and they are right around what an lb7 injector is (about .4 ohms R). I'm sending a tach signal to the engine speed pin that is a 50% duty cycle 0-5v wave with 2 pulses per rev.
I think I need to find someone who rebuilds or bench tests these to see if they can offer insight.
My next step is to buy the ECU for the truck and use that to read FICM diagnostics with a scanner.
Unfortunately these don't seem to fail like the Ford 6.0L FICM's do so there is VERY little info out there on them.
I don't pay nothing for anything.
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