2 Wheel Drive T-Case Fault U0102

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Jan 13, 2023
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Houston, Texas
Ram Year
My 2012 1500 SLT 4.7L FlexFuel *** RWD *** has a fault code that I cannot understand. U0102 shows up and supposedly is a communication issue with the T-Case.
This showed up when I was at the very end and fixed a C121E code that resulted in essentially replacing the entire braking system until I got to the final parts which were the ABS pump, valve body and control module. I read some warnings from people that the control module, pump, and valve body should all stay together. I purchased a used set to at least help me diagnose the issue before I spent quite a sum on new parts, if I needed new parts.
Apparently, the parts that were sent to me as an "exact match" according to the seller were the right parts, but were installed on a 4x4 model and the control module couldn't communicate with the T-Case because there isn't one.
After doing some checks, I found that the C121E was being caused by my valve body as it was allowing brake fluid, when under pressure, to leak back into the system, specifically into the opposite two wheels that were not part of the traction control immediate action. If the front left and back right were engaged with pressurized brake fluid, then the front right and back left should be freely spinning, but they were receiving brake fluid due to something not sealing properly.
Seeing that the control module was seeking a T-Case and initiated the U0102 code, I swapped the newly replaced module out with the original control module. Unfortunately, the U0102 remained and is still there. The good news is that the C121E is now gone, has not returned, and I assume was caused by an internal seal that was remedied with the new valve body and pump.

Does anyone know how to inform the truck that it's a rear wheel drive street truck and not a 4x4 mudder without hurting it's feelings, thus causing more fault codes?

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