Problem: Initial startup on cold mornings (30 degrees), lift pump doesn't start running (0 psi). Stop motor, bump starter a couple times until LP starts and all is well the rest of the day (14-15psi).

My theory: The wiring diagram shows the ECM controls the LP. My batteries are getting weak and it's very apparent in the morning (slow turn over). I think the startup is taking nearly all available power not leaving enough for the ECM to handle all of its duties like firing up the pump. Why it remains off even after start up is a mystery unless that function of the ECM is a one shot occurance (start it and forget it kinda thing).

Additional info: When I installed the LP relo kit a few weeks ago I hooked up one battery to bump the starter and bleed the line. The pump didn't run until I attached both batteries. Both batteries show their litle green dot and the pump is a new Campaign from Cummins.

Thoughts...