GMPP 376/480 Crank No start

[1967GMC]

I have had this truck running for a couple years it has cut off while driving a few times, then started back up after a few attempts. Now I cannot get it to start at all. It is throwing a 1682 code (ignition 1 circuit 2) I have tried a new battery (per someones advice) I have tried bypassing the ignition switch, checked all fuses and relays. I can't find a GMPP pinout for the e67 ecm used on this motor to test those. any help will be much appreciated.

[79 Camaro]

Have you checked the fuel pump and have fuel pressure at the fuel rail.
And I just have to ask do you have plenty of fuel in the tank?

[1967GMC]

Yes, full tank and 58 psi. sometimes the pump doesn't come one though

[1967GMC]

Double checking found a bad PT relay. So far it’s running again