My apologies for being a salty cracker in the previous post...one little update FWIW.
Stewing in my melancholy I was thinking through the schematics, just rolling the last six weeks over in my to see if something - anything - would come to mind that I could recheck.
5 volt ref's came up, specifically was there a 5v ref for the trans, and if so what else would be on that circuit?
I don't think there is a 5v ref for the trans, but there are two sensors on the engine called out on the transmission control page that *do* share the same 5v source and those are MAP and TPS.
I have used spares for both, and had changed out the MAP when this failure first happened, why I don't know - I was just hunting and pecking to uncover a problem and I didn't know nearly as much about the system then as I have learned now.
So after changing the trans harness and still being in limp mode yesterday I was pretty well stumped on where to go next (except to the junkyard) so I changed out the MAP for the old one.
Problem went away. When this thing runs right it runs really good, and it was back to it's old self.
So my theories about why this has been such a headache, I believe the MAP did go bad, perhaps the one I'd originally changed out was also tired, if it was pulling the 5v ref to ground it would also pull ref power for the TPS, and since the PCU needs both signals to control output's for the trans I can see why I was getting limp mode there.
There may be some additional issues yet that I haven't found, I did find and repair some overheated wiring that routes over the left side exhaust manifold and sends power to the fuel pump & sender and that may have pulled too much current at the PCU to begin with, right now that part of the electrics seems to be working ok.
So I have a new MAP ordered and will pop that in tomorrow and see if it gets me back on the road.
I really did think I'd killed the second PCU and I was pretty upset about that, but maybe it isn't as bad as I had feared.
Anywho, that's the update, I know I'm not the only one who's gone rounds with a 7060 PCU so maybe someday this will be useful to someone else.
Edit - Nevermind. Still bad. Thought I'd recheck fuel pump wire through it's connector. Key on after that & it's back to brain dead.
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