engine controls, circuit 439, 98 l31

[ISwearItsStock]

This circuit is hot in run and crank and supplies the PCM, ICM, ckp sensor and injector coils with 12v+, so am I safe to assume that it shouldn't act as a ground with the key off? Only makes sense that there's a short to ground right? This is with PCM disconnected.
Its -25c now so I quit for the day, but I will test again with the other modules disconnected tomorrow I suppose and I hope its not wiring.
Injection wasn't squirting when I had the upper off and the poppets out. Spark was good on cylinder 1 after I changed the wires and rotor. Fuel pressure is good. I know they like 60psi.
Vtd is inactive during crank, 0.0 average pwm on crank, ignition 1 high shows no but I don't see ho the comp would read a highV on this setup... Ign 1 low is yes cranking. Could my coil or module be intermittently shorting internally? Guess I should just relax and finish isolating this in the daylight. I appreciate any and all input though.

 

[SAATR]

Are you checking this with a test light or a multi meter? And have you checked for continuity to ground with the battery disconnected, or connected to the battery positive post with a test light and probed circuit 439?

 

[ISwearItsStock]

Yes, used a DMM with batt d/c'd. Going now to finish up since it looks like it isn't getting any warmer out... -19°c lol -30 with the w.c.. F%$k yeah!

Update: checked all connectors with that pink #439 in it and they're all purdy. Disconnected the harness completely but the DMM didn't like the weather. I'll keep y'all posted. Supposed to go up 10° tomorrow and its too dark now anyway.

Update 2.0: wow. Just looked at schematics... Wow. That's all. I have FAR from checked all connections. That's the biggest single circuit in the whole truck! Where to start...