Hi Scott, my name is ***** ***** you for asking your question, I will try and help you out.
I am a Master Technician with over 30+ years experience that's dedicated to giving you the best Answer possible.
I need to ask you a couple questions hope you don't mind.
When truck would not crank does check engine light come on and go off?
When it cranked but won't start did check engine light come on and go off?
No communication to com port indicates ecm is not powering up,, paying attention to check engine light will tell us where to go
Does this have a standard shift trans,,ultrashift,autoshift?
Clutch pedal yes/no?
What is it doing right now as far as cranking and light?
Is this a DDEC 4?
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