U0102 Fault Code for T-Case - But Its a 2012 RAM 1500 SLT 4.7L Rear Wheel Drive - Not T-Case Equipped!

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Jan 13, 2023
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Houston, Texas
Ram Year
For the last year and then some, I've fought a C121E that I finally found the cause and answer to when I swapped out the ABS control module, pump, and valve body (or it was the three of six shattered phenolic pistons that were only 6 months old). The ABS control module, valve body, and pump that I used were sent together and were used. In reading through forums and discussing this issue with mechanics, I heard from several that these three items should remain together if possible. So, I kept the used group that I purchased together when I installed them even though I was fairly confident that the original control unit from my truck was good and I had rebuilt it by re-flowing all of the solder joints in it (it was a true pain in the butt).
After installing the replacement ABS control, valve body, and pump, new dash lights were illuminated referring to fault codes that I found after I ran a fault check using AlfaOBD. The control module, which had the same part number and identical markings as the original, was actually from a 2012 Ram 1500 4x4 when my truck is a 2012 Ram 1500 4.7L RWD SLT. After deliberating what damage, if any, could result from putting the original ABS control back in and understanding that the cause of the C121E was brake fluid pushing past the valve body and into the lines of the opposite brakes from the ones needing traction help, I decided to put the original control module back in with the replacement valve body and pump. Putting the original ABS control module back in darkened the dash new dash lights that illuminated with the replacement ABS control module. However, when I did another fault code check and there was one code remaining that has been very persistant and stubborn.
U0102 lost communication to the T-Case module (or something like that) is the remaining fault code that I don't know what to do to permanently clear it. I've cleared the fault codes, but that one keeps returning. Since my truck is two wheel drive, as far as I know, there is no transfer case, and that is the problem.

How do restore communication with a device with the goal of clearing the fault, if the module isn't a part of my truck?

The only other persistant code that the truck has that I don't know what more to do for a fix is a U1147 code for an unknown can-bus module. This started after installing a Pheonix Automotive T-Style head unit. Any advice here would be welcome.

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