transmission issue, code u0101?

2011 MAZDA 3
174,000 MILES • 4 CYL • 2WD • AUTOMATIC
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BHAMDOC1973
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is this a possible PCM issue? code u0101. something isn't right.
Oct 23, 2022 at 8:06 AM
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STRAILER
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The code U0101 means the TCM, is unable to communicate. Start by checking the fuses and if all are okay, I would replace the TCM. here is the location and how to do the job in the images below. Fortunately, it does not require reprogramming. Check out the images (below). Let us know what happens and please upload pictures or videos of the problem.
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Oct 24, 2022 at 4:26 AM
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BHAMDOC1973
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I see. You mean just fuses in general? So, the TCM is under the battery on top of the transmission?
Oct 24, 2022 at 4:28 AM
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STRAILER
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Yes, and yes, check all fuses and let me know.
Oct 25, 2022 at 6:43 AM
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BHAMDOC1973
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Can you provide the diagram to the TCM wires? I want to check the CAN wires as they may be loose, corrosion, or the pins are too loose on inside before replacing the TCM. I have seen one video where this was their issue after they probed one wire all came to life.
Oct 27, 2022 at 4:17 AM
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STRAILER
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Sure, here you go, and I have included a guide on how to check the TCM wiring and connections.

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

Check out the images (below). Please let us know what happens.
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Professional Diagram for 2CarPros Members
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Oct 29, 2022 at 7:03 AM
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