Transmission limp mode or nothing?

2001 CHEVROLET 2500
325,000 MILES • 6.6L • V8 • TURBO • 4WD • AUTOMATIC
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3KR
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Transmission (Allison 1000) goes into limp mode or nothing. I thoroughly cleaned the valve body, load tested the internal harness and solenoids, checked OHMS, replaced the high-pressure shift valve, no burnt fluid. Codes indicate valve C, D, E, not working. I have been trying to load-test the harness and can't find a wire diagram that matches the harness. At the connector to the transmission position A is a pink wire, (diagram says should be dark green) at the TCM Red connector I have Position 1 pink as well, but my wire diagram from ATSG says it should be blue? Transmission and wires have never been touched by 1 owner. I will attach the diagram I am working from.
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Apr 21, 2023 at 4:59 AM
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STRAILER
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What code numbers are they? Here is a guide to help you test the harness, and the transmission wiring diagrams in the images below.

https://www.2carpros.com/articles/how-to-check-wiring

Check the power and grounds to the TCM module, you might have a TCM that is going out. Check out the images (below). Please let us know what happens.
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Apr 21, 2023 at 4:41 PM
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3KR
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Thanks Ken,

Codes i get are P0763.768.773,1710, they repeat, once cleared, sometimes they stay cleared, and the truck will drive in limp mode, sometimes it takes 2 or 3 attempts to clear them, The number of codes I get changes each time I scan sometimes i get 12 other times 8 or 7 or just 2. Looking at the wire diagram I see pink wire in location1, is that the red connector to the TCM? Tomorrow I will verify the colors by order of the red connector at the TCM. Based on your diagram I need to verify the color and location of the wires, can you verify colors for locations A,B,C,D of the round connector that plugs into the trans (there are 17 wires which matches your diagram), I am confused a little by the letter codes on the diagram.
Apr 21, 2023 at 6:42 PM
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STRAILER
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They don't give us the color of the connector, the #2 pin (pink) should have power. It sounds like to me the TCM is out.
Apr 22, 2023 at 10:47 AM