cranking with the key on

dndj

Boost!
Apr 13, 2019
292
32
28
Oregon
From what I am reading above, I'm guessing it's related to lack of ECM grounding. You provided solid bench power and ground and you're able to communicate with it over the class 2 data bus.

ECM is grounded by G102 which should be on the engine block. Check carefully for missed ground connections on the engine block.

Here's the starter schematic. Starter spins when ECM grounds the control side of the starting relay.
 

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danzick

playing with fire
Feb 20, 2014
521
12
18
Livingston, MT
From what I am reading above, I'm guessing it's related to lack of ECM grounding. You provided solid bench power and ground and you're able to communicate with it over the class 2 data bus.

ECM is grounded by G102 which should be on the engine block. Check carefully for missed ground connections on the engine block.

Here's the starter schematic. Starter spins when ECM grounds the control side of the starting relay.
I would love if it was that simple. I have three ground wires on each side of the block down low by the front cover, and I have the one braded line from the back of the drivers head to the firewall. does that sound like all of them?
 

danzick

playing with fire
Feb 20, 2014
521
12
18
Livingston, MT
those schematics are hard to follow for me. The first one is the same as my haynes manual. It shows like three grounds for the engine when I have like seven going to the engine total. the second one shows grounds toward the rear of the engine? I only have the one on the drivers side. Nothing for the passenger side? it also shows a GD for the Modules I think on the drivers side. Anyone know which one it is? I have three. two real small ones, and the big battery one. There is three that I can think of that were not onboard with the engine harness. Two big battery GD's and the one from the drivers head to the cab I originally forgot.
 

danzick

playing with fire
Feb 20, 2014
521
12
18
Livingston, MT
well guys I think I got it figured out. I finally got the idea to take my spare engine compartment harness that came with my core engine and spread it on the floor to look for missing grounds. I found a ground wire that runs with the starter signal wire. I followed my truck harness and sure enough, it got tucked behind the big plastic thing that mounts to the upper oil pan. I connected it, and now my indicator under the PRND123 shows up in park, it says driver 1 now, and when I go to crank, the test light comes on.
 

danzick

playing with fire
Feb 20, 2014
521
12
18
Livingston, MT
I actually fired it on my lunch break today. the only issue I have now is a glow plug code is getting tripped. I'll have to track that down.