Hello ,having a problem with my truck yesterday...Ran fine all day,starting and stopping. Park in the street, went to move it later, just cranks and cranks .Disconnected battery's, let it sit overnight, Starting right up this morning..........Only code i ever get is PO1694.What.is strange, Does out every April in warm months, comes back in October in the cold, Done this for three years I've had it...

thinking ECM maybe?

How are you checking for codes?  Does your code clear? Does this happen when you park uphill, downhill or is it level?  Could this be air getting into the fuel system, and have you tried cracking open injector lines to see if this helps it start?  If your ECM were going you would probably see a slew of other issues and fault codes.  Does your WTS light come on?  What mods have you done to the truck?  Tuners? Lift pump?

In the order of questions;1694 would clear and come back on,in summer warm months it stays off . level ground/ 3/4 tank. Doubt it. WTS seems to take longer when 1694 code set, In summer when code out doesn't come on half the time starts fine..... Fuel system is Air Dog Pump, 1/2 pickup in tank, Edge programmer,  Banks intake.

Also has torque converter lockup issues with check E light on ,nothing with it out.

PO1694 code points to an electrical problem, no communication between ecm and pcm. I had a similar issue awhile back. Check your main plug in the PDC fuse box under hood, Mine was a little loose causing the code, I cleaned and resealed the connection and code has not returned.   Hope this helps, might get you going in the right direction at least 

Did that last year, nothing changed

Dang... other  than checking connections , relays and grounds I wouldn't know how to further diagnose the ecm..

 

when getting the no start are you developing fuel pressure? Is lift pump comming on?

Commuication issues can be rough. Did you check the ECM plug for issues? There is a second plug on the cowl near the valve cover that could be loose double check those.

Going to check all the connectors this week .Will update what i find....Thanks for all the help.

 

Then the CCD network wire map...

Check electrical rail below the battery for loose connections.

Two plugs by the valve cover. Then the plug in the PDC that is bolted down.