Code U10100, TCM lost connection?

2009 MAZDA 3
143,000 MILES • 2.5L • 2WD • AUTOMATIC
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JAKE955
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  • 1 POST
I've replaced my TCM in my vehicle listed above, however I've been told that it was originally a manual. That's not how I brought it though. I've had it for 7 months the TCM in it originally was changed a year ago. The new TCM has cleared the U010100 code which showed warning lights of AT and traction control and engine light warnings. However, it has returned after changing the TCM. The car listed above is a sp25 and I've remounted the TCM on the firewall, so it doesn't get hot any other suggestions with only the U10100 code coming up that's all.
Feb 11, 2024 at 5:31 AM
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JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
  • 110,194 POSTS
  • ASE Certified Mechanic
Hi,

The optional engines for this are a 2.0L and a 2.3L. Let me know which one you have. Also, if you could provide the VIN, I can check what transmission it had originally.

Next, is this problem new only since the TCM was changed? Could you also reconfirm the code? I'm not showing that code for this vehicle regardless of engine size.

Let me know.

Joe
Feb 11, 2024 at 3:33 PM
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